KLDO / Kaleido Biosciences, Inc. - Pemfailan SEC, Laporan Tahunan, Penyata Proksi

Kaleido Biosciences, Inc.
US ˙ OTCPK ˙ US4833471000

Statistik Asas
CIK 1751299
SEC Filings
All companies that sell securities in the United States must register with the Securities and Exchange Commission (SEC) and file reports on a regular basis. These reports include company annual reports (10K, 10Q), news updates (8K), investor presentations (found in 8Ks), insider trades (form 4), ownership reports (13D, and 13G), and reports related to the specific securities sold, such as registration statements and prospectus. This page shows recent SEC filings related to Kaleido Biosciences, Inc.
SEC Filings (Chronological Order)
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May 6, 2022 15-12B

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 15 CERTIFICATION AND NOTICE OF TERMINATION OF REGISTRATION UNDER SECTION 12(g) OF THE SECURITIES EXCHANGE ACT OF 1934 OR SUSPENSION OF DUTY TO FILE REPORTS UNDER SECTIONS 13

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 15 CERTIFICATION AND NOTICE OF TERMINATION OF REGISTRATION UNDER SECTION 12(g) OF THE SECURITIES EXCHANGE ACT OF 1934 OR SUSPENSION OF DUTY TO FILE REPORTS UNDER SECTIONS 13 AND 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934. 001-38822 Commission File Number KALEIDO BIOSCIENCES, INC. (Exact name of registrant as specified i

April 25, 2022 S-8 POS

As filed with the Securities and Exchange Commission on April 25, 2022

S-8 POS 1 d344833ds8pos.htm S-8 POS As filed with the Securities and Exchange Commission on April 25, 2022 Registration No. 333-238123 UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 POST-EFFECTIVE AMENDMENT NO. 1 TO: FORM S-8 REGISTRATION STATEMENT NO. 333-238123 UNDER THE SECURITIES ACT OF 1933 KALEIDO BIOSCIENCES, INC. (Exact name of registrant as specified in its charter)

April 25, 2022 S-8 POS

As filed with the Securities and Exchange Commission on April 25, 2022

S-8 POS 1 d344833ds8pos.htm S-8 POS As filed with the Securities and Exchange Commission on April 25, 2022 Registration No. 333-230167 UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 POST-EFFECTIVE AMENDMENT NO. 1 TO: FORM S-8 REGISTRATION STATEMENT NO. 333-230167 UNDER THE SECURITIES ACT OF 1933 KALEIDO BIOSCIENCES, INC. (Exact name of registrant as specified in its charter)

April 25, 2022 S-8 POS

As filed with the Securities and Exchange Commission on April 25, 2022

As filed with the Securities and Exchange Commission on April 25, 2022 Registration No.

April 25, 2022 POS AM

As filed with the Securities and Exchange Commission on April 25, 2022

As filed with the Securities and Exchange Commission on April 25, 2022 Registration No.

April 18, 2022 25

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D. C. 20549 FORM 25 NOTIFICATION OF REMOVAL FROM LISTING AND/OR REGISTRATION UNDER SECTION 12(b) OF THE SECURITIES EXCHANGE ACT OF 1934. Commission File Number 001-38822 KALEIDO BIOSCIENCES

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D. C. 20549 FORM 25 NOTIFICATION OF REMOVAL FROM LISTING AND/OR REGISTRATION UNDER SECTION 12(b) OF THE SECURITIES EXCHANGE ACT OF 1934. Commission File Number 001-38822 KALEIDO BIOSCIENCES, INC. THE NASDAQ GLOBAL SELECT MARKET (Exact name of Issuer as specified in its charter, and name of Exchange where security is listed and/or registe

April 8, 2022 8-K

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Notice of Delisting or Failure to Satisfy a Continued Listing Rule or Standard; Transfer of Listing, Financial Statements and Exhibits, Other Events

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): April 8, 2022 KALEIDO BIOSCIENCES, INC. (Exact name of Registrant as Specified in Its Charter) Delaware 001-38822 47-3048279 (State or Other Jurisdiction of Incorporation) (Commission

April 1, 2022 EX-10.16

Fourth Amendment to Loan and Security Agreement, dated March 25, 2022.

EXHIBIT 10.16 CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED BY [***], HAS BEEN OMITTED BECAUSE IT IS NOT MATERIAL AND WOULD LIKELY CAUSE COMPETITIVE HARM TO THE COMPANY IF PUBLICLY DISCLOSED. Execution Version FOURTH AMENDMENT TO LOAN AND SECURITY AGREEMENT THIS FOURTH AMENDMENT TO LOAN AND SECURITY AGREEMENT (this ?Amendment?), dated as of March 25, 2022 (the ?Amendment Effe

April 1, 2022 10-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K ? ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2021 or ? TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-38822 KALEIDO BIOSCIENCES, INC.

April 1, 2022 NT 10-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 12b-25 NOTIFICATION OF LATE FILING (Check one): ☒ Form 10-K ☐ Form 20-F ☐ Form 11-K ☐ Form 10-Q ☐ Form 10-D ☐ Form N-SAR ☐ Form N-CSR For Period Ended: December 31, 2021 ☐ T

NT 10-K 1 d291927dnt10k.htm NT 10-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 12b-25 NOTIFICATION OF LATE FILING (Check one): ☒ Form 10-K ☐ Form 20-F ☐ Form 11-K ☐ Form 10-Q ☐ Form 10-D ☐ Form N-SAR ☐ Form N-CSR For Period Ended: December 31, 2021 ☐ Transition Report on Form 10-K ☐ Transition Report on Form 20-F ☐ Transition Report on Form 11-K ☐ Transition Repor

March 17, 2022 8-K

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Financial Statements and Exhibits

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): March 17, 2022 (March 13, 2022) KALEIDO BIOSCIENCES, INC. (Exact name of Registrant as Specified in Its Charter) Delaware 001-38822 47-3048279 (State or Other Jurisdiction of Incorpor

March 9, 2022 8-K

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): March 09, 2022 (March 4, 2022) KALEIDO BIOSCIENCES, INC. (Exact name of Registrant as Specified in Its Charter) Delaware 001-38822 47-3048279 (State or Other Jurisdiction of Incorpora

January 28, 2022 8-K

Other Events

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): January 28, 2022 KALEIDO BIOSCIENCES, INC. (Exact name of Registrant as Specified in Its Charter) Delaware 001-38822 47-3048279 (State or Other Jurisdiction of Incorporation) (Commiss

November 1, 2021 EX-99.1

Kaleido Biosciences Reports Third Quarter 2021 Financial Results --Achieved primary objective of safety and tolerability in clinical study evaluating KB295 in mild-to-moderate ulcerative colitis; meaningful reduction observed in key biomarkers correl

Exhibit 99.1 Kaleido Biosciences Reports Third Quarter 2021 Financial Results -Achieved primary objective of safety and tolerability in clinical study evaluating KB295 in mild-to-moderate ulcerative colitis; meaningful reduction observed in key biomarkers correlated with disease activity and inflammation- -Remain on track to initiate Phase 2 clinical trials of KB109 in COPD and KB295 in UC in firs

November 1, 2021 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): November 01, 2021 KALEIDO BIOSCIENCES, INC. (Exact name of Registrant as Specified in Its Charter) Delaware 001-38822 47-3048279 (State or Other Jurisdiction of Incorporation) (Commis

November 1, 2021 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ? QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended September 30, 2021 or ? TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-3882

October 5, 2021 8-K

Financial Statements and Exhibits, Other Events

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): October 4, 2021 KALEIDO BIOSCIENCES, INC. (Exact name of registrant as specified in its charter) Delaware 001-38822 47-3048279 (State or other jurisdiction of incorporation) (Commissi

October 5, 2021 EX-99.1

Forward-Looking Statements This presentation also contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended, including, without limitation, statements regarding our strategy, business p

Kaleido R&D Day October 5, 2021 Exhibit 99.1 Company Logo?2021KALEIDO?1 Forward-Looking Statements This presentation also contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended, including, without limitation, statements regarding our strategy, business plans and focus, including the therapeutic potential of our Microbiome Metaboli

October 5, 2021 EX-99.2

Kaleido Biosciences Announces New Clinical and Preclinical Data Supporting Advancement of KB295 to a Phase 2 Clinical Study in Mild-to-Moderate Ulcerative Colitis KB295 reached its primary endpoint demonstrating favorable safety and tolerability prof

Exhibit 99.2 Kaleido Biosciences Announces New Clinical and Preclinical Data Supporting Advancement of KB295 to a Phase 2 Clinical Study in Mild-to-Moderate Ulcerative Colitis KB295 reached its primary endpoint demonstrating favorable safety and tolerability profile Reduction in key ulcerative colitis biomarkers correlated with disease activity and inflammation - fecal calprotectin, fecal lactofer

September 3, 2021 8-K

Other Events

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): August 27, 2021 KALEIDO BIOSCIENCES, INC. (Exact name of registrant as specified in its charter) Delaware 001-38822 47-3048279 (State or other jurisdiction of incorporation) (Commissi

September 2, 2021 POS EX

As filed with the Securities and Exchange Commission on September 2, 2021

As filed with the Securities and Exchange Commission on September 2, 2021 Registration No.

August 11, 2021 EX-99.1

--On track to report topline data from a clinical study of KB295 in patients with mild-to-moderate ulcerative colitis by end of third quarter-- --Kaleido and the COPD Foundation to collaborate on the development of KB109 in patients with COPD; plan t

Exhibit 99.1 -On track to report topline data from a clinical study of KB295 in patients with mild-to-moderate ulcerative colitis by end of third quarter- -Kaleido and the COPD Foundation to collaborate on the development of KB109 in patients with COPD; plan to initiate Phase 2 clinical study in first quarter 2022- -Additional data from an observational clinical study of KB109 in patients with mil

August 11, 2021 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ? QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2021 or ? TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-38822 KAL

August 11, 2021 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): August 11, 2021 KALEIDO BIOSCIENCES, INC. (Exact name of registrant as specified in its charter) Delaware 001-38822 47-3048279 (State or other jurisdiction of incorporation) (Commissi

August 9, 2021 EX-99.1

Kaleido Biosciences Announces New Chairperson Appointment to its Board of Directors –Current Director Theo Melas-Kyriazi appointed Chairperson of the Board of Directors–

Exhibit 99.1 Kaleido Biosciences Announces New Chairperson Appointment to its Board of Directors ?Current Director Theo Melas-Kyriazi appointed Chairperson of the Board of Directors? LEXINGTON, MA?August 9, 2021?Kaleido Biosciences, Inc. (Nasdaq: KLDO), a clinical-stage healthcare company with a differentiated, chemistry-driven approach to targeting the microbiome to treat disease and improve huma

August 9, 2021 8-K

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Financial Statements and Exhibits

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): August 3, 2021 KALEIDO BIOSCIENCES, INC. (Exact name of registrant as specified in its charter) Delaware 001-38822 47-3048279 (State or other jurisdiction of incorporation) (Commissio

July 2, 2021 8-K

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): July 1, 2021 KALEIDO BIOSCIENCES, INC. (Exact name of registrant as specified in its charter) Delaware 001-38822 47-3048279 (State or other jurisdiction of incorporation) (Commission

June 17, 2021 8-K

Financial Statements and Exhibits, Other Events, Submission of Matters to a Vote of Security Holders

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): June 14, 2021 KALEIDO BIOSCIENCES, INC. (Exact name of registrant as specified in its charter) Delaware 001-38822 47-3048279 (State or other jurisdiction of incorporation) (Commission

June 17, 2021 EX-99.1

Forward-Looking Statements This presentation also contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended, including, without limitation, statements regarding our strategy, business p

Leading a Novel Approach to Targeting the Microbiome NASDAQ: KLDO June 2021 Exhibit 99.

May 5, 2021 DEFA14A

- DEFA14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A (Rule 14a-101) Information Required in Proxy Statement Schedule 14A Information Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 Filed by the Registrant ? Filed by a Party other than the Registrant ? Check the appropriate box: ? Preliminary Proxy Statement ? Confidential, for Use of

May 5, 2021 EX-23..1

Consent of Deloitte & Touche LLP

Exhibit 23.1 CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM We consent to the incorporation by reference in this Registration Statement No. 333-240323 on Form S-3 of our report dated March 3, 2021 relating to the financial statements of Kaleido Biosciences, Inc., appearing in the Annual Report on Form 10-K of Kaleido Biosciences, Inc. for the year ended December 31, 2020. We also consent

May 5, 2021 POS AM

- POS AM

As filed with the Securities and Exchange Commission on May 5, 2021 Registration No.

May 5, 2021 DEF 14A

- DEF 14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A (Rule 14a-101) Information Required in Proxy Statement Schedule 14A Information Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 Filed by the Registrant ? Filed by a Party other than the Registrant ? Check the appropriate box: ? Preliminary Proxy Statement ? Confidential, for Use of

May 5, 2021 S-8

No. 333-255773

Table of Contents As filed with the Securities and Exchange Commission on May 5, 2021 Registration No.

May 4, 2021 EX-10.1

Third Amendment to Loan and Security Agreement, dated April 30, 2021, by and among Kaleido Biosciences, Inc. and each of its Qualified Subsidiaries (including Cadena Bio, Inc.), the several banks and other financial institutions or entities from time to time parties to the Loan Agreement and Hercules Capital, Inc.

Exhibit 10.1 CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED BY [***], HAS BEEN OMITTED BECAUSE IT IS NOT MATERIAL AND WOULD LIKELY CAUSE COMPETITIVE HARM TO THE COMPANY IF PUBLICLY DISCLOSED. THIRD AMENDMENT TO LOAN AND SECURITY AGREEMENT THIS THIRD AMENDMENT TO LOAN AND SECURITY AGREEMENT (this ?Amendment?), dated as of April 30, 2021 (the ?Amendment Effective Date?), is made

May 4, 2021 EX-99.1

Kaleido Biosciences Reports First Quarter 2021 Financial Results --Positive results in patients with mild-to-moderate COVID-19 demonstrate KB109’s potential to reduce healthcare utilization and recovery time; initiating IND application to support fur

Exhibit 99.1 Kaleido Biosciences Reports First Quarter 2021 Financial Results -Positive results in patients with mild-to-moderate COVID-19 demonstrate KB109?s potential to reduce healthcare utilization and recovery time; initiating IND application to support further development- -Topline data from a clinical study of KB295 in patients with mild-to-moderate ulcerative colitis on track for mid-2021-

May 4, 2021 10-Q

Quarterly Report - 10-Q

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ? QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2021 or ? TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-38822 KA

May 4, 2021 8-K

Entry into a Material Definitive Agreement, Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 4, 2021 KALEIDO BIOSCIENCES, INC. (Exact name of registrant as specified in its charter) Delaware 001-38822 47-3048279 (State or other jurisdiction of incorporation) (Commission F

March 24, 2021 8-K

Financial Statements and Exhibits, Other Events

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): March 24, 2021 KALEIDO BIOSCIENCES, INC. (Exact name of registrant as specified in its charter) Delaware 001-38822 47-3048279 (State or other jurisdiction of incorporation) (Commissio

March 24, 2021 EX-99.2

Kaleido Biosciences Reports Positive Results from Non-IND Study Demonstrating a Reduction in COVID-19 Related Healthcare Utilization and Recovery Time in Patients with Mild-to-Moderate COVID-19 and One or More Comorbidity KB109 demonstrated favorable

Exhibit 99.2 Kaleido Biosciences Reports Positive Results from Non-IND Study Demonstrating a Reduction in COVID-19 Related Healthcare Utilization and Recovery Time in Patients with Mild-to-Moderate COVID-19 and One or More Comorbidity KB109 demonstrated favorable safety and tolerability profile Kaleido intends to file an Investigational New Drug (IND) application, with the goal of advancing KB109

March 24, 2021 EX-99.1

Forward-Looking Statements This presentation also contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended, including, without limitation, statements regarding our strategy, business p

K031 Topline Final Data Analysis March 24, 2021 Exhibit 99.1 Forward-Looking Statements This presentation also contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended, including, without limitation, statements regarding our strategy, business plans and focus, including the therapeutic potential of our Microbiome Metabolic Therapy (

March 3, 2021 EX-4.3

Description of Registrant’s Securities.

Exhibit 4.3 Description of the Registrant?s Securities Registered Pursuant to Section 12 of the Securities Exchange Act of 1934, as amended The summary of the general terms and provisions of the registered securities of Kaleido Biosciences, Inc. (?Kaleido? ?we,? or ?our?) set forth below does not purport to be complete and is subject to and qualified in its entirety by reference to our Amended and

March 3, 2021 EX-99.1

Kaleido Biosciences Reports Fourth Quarter and Full Year 2020 Financial Results Topline data from two ongoing COVID-19 studies with KB109 expected in Q1 2021 KB295 study in patients with ulcerative colitis remains on track with topline data anticipat

Exhibit 99.1 Kaleido Biosciences Reports Fourth Quarter and Full Year 2020 Financial Results Topline data from two ongoing COVID-19 studies with KB109 expected in Q1 2021 KB295 study in patients with ulcerative colitis remains on track with topline data anticipated mid-year 2021 LEXINGTON, MA?March 3, 2021?Kaleido Biosciences, Inc. (Nasdaq: KLDO), a clinical-stage healthcare company with a differe

March 3, 2021 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): March 3, 2021 KALEIDO BIOSCIENCES, INC. (Exact name of registrant as specified in its charter) Delaware 001-38822 47-3048279 (State or other jurisdiction of incorporation) (Commission

March 3, 2021 EX-21.1

Subsidiaries of the Registrant

Exhibit 21.1 SUBSIDIARIES Subsidiary Jurisdiction of Incorporation Cadena Bio, Inc. Delaware Kaleido Biosciences Securities Corporation Massachusetts

March 3, 2021 10-K

Annual Report - 10-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K ? ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2020 or ? TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-38822 KALEIDO BIOSCIENCES, INC.

February 16, 2021 SC 13G

SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. )* Kaleido Biosciences, Inc. (Name of Issuer) Common Stock, par value $0.001 per share (Title of Class of Securities) (CUS

Schedule 13G SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. )* Kaleido Biosciences, Inc. (Name of Issuer) Common Stock, par value $0.001 per share (Title of Class of Securities) 483347100 (CUSIP Number) December 31, 2020 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the

February 16, 2021 EX-99.1

AGREEMENT REGARDING THE JOINT FILING OF SCHEDULE 13G

EX-99.1 Exhibit 99.1 AGREEMENT REGARDING THE JOINT FILING OF SCHEDULE 13G Pursuant to Rule 13d-1(k)(1) promulgated under the Securities Exchange Act of 1934, as amended, the undersigned agree that the Statement on Schedule 13G to which this Exhibit is attached is filed on behalf of each of them. Each of them is individually eligible to use the Schedule 13G to which this Exhibit is attached. Each o

February 10, 2021 SC 13D/A

SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13D Under the Securities Exchange Act of 1934 (Amendment No. 2)* Kaleido Biosciences, Inc. (Name of Issuer) Common Stock, par value $0.001 per share (Title of Class of Securities) (CU

Schedule 13D/A SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13D Under the Securities Exchange Act of 1934 (Amendment No. 2)* Kaleido Biosciences, Inc. (Name of Issuer) Common Stock, par value $0.001 per share (Title of Class of Securities) 483347100 (CUSIP Number) Noubar B. Afeyan, Ph.D. Flagship Ventures 55 Cambridge Parkway, Suite 800E Cambridge, MA 02142 (617) 868-1888 (Na

February 10, 2021 EX-99.1

JOINT FILING AGREEMENT

Exhibit 1 Exhibit 1 JOINT FILING AGREEMENT The persons below hereby agree that the Schedule 13D to which this agreement is attached as an exhibit, as well as all future amendments to such Schedule 13D, shall be filed jointly on behalf of each of them.

February 8, 2021 8-K

Entry into a Material Definitive Agreement, Financial Statements and Exhibits, Other Events - 8-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): February 3, 2021 KALEIDO BIOSCIENCES, INC. (Exact name of registrant as specified in its charter) Delaware 001-38822 47-3048279 (State or other jurisdiction of incorporation) (Commiss

February 8, 2021 EX-99.2

Kaleido Biosciences Announces Pricing of Public Offering of Common Stock

EX-99.2 Exhibit 99.2 Kaleido Biosciences Announces Pricing of Public Offering of Common Stock LEXINGTON, Mass., February 3, 2021 – Kaleido Biosciences, Inc. (Nasdaq: KLDO), a clinical-stage healthcare company with a differentiated, chemistry-driven approach to targeting the microbiome to treat disease and improve human health, today announced the pricing of an underwritten public offering of 5,250

February 8, 2021 EX-99.1

Kaleido Biosciences Announces Proposed Public Offering of Common Stock

EX-99.1 Exhibit 99.1 Kaleido Biosciences Announces Proposed Public Offering of Common Stock LEXINGTON, Mass., February 3, 2021 – Kaleido Biosciences, Inc. (Nasdaq: KLDO), a clinical-stage healthcare company with a differentiated, chemistry-driven approach to targeting the microbiome to treat disease and improve human health, today announced that it intends to sell, subject to market and other cond

February 8, 2021 EX-1.1

Underwriting Agreement, dated February 3, 2021, by and between Kaleido Biosciences, Inc. and Morgan Stanley & Co. LLC and Piper Sandler & Co., as representatives of underwriters named therein

EX-1.1 Exhibit 1.1 KALEIDO BIOSCIENCES, INC. 5,250,000 Shares of Common Stock Underwriting Agreement February 3, 2021 Morgan Stanley & Co. LLC Piper Sandler & Co. As Representatives of the several Underwriters listed in Schedule 1 hereto c/o Morgan Stanley & Co. LLC 1585 Broadway New York, New York 10036 c/o Piper Sandler & Co. U.S. Bancorp Center 800 Nicollet Mall Minneapolis, Minnesota 55402 Lad

February 5, 2021 424B5

5,250,000 Shares Common Stock

424B5 Table of Contents Filed Pursuant to Rule 424(b)(5) Registration No. 333-240323 PROSPECTUS SUPPLEMENT (to Prospectus dated August 14, 2020) 5,250,000 Shares Common Stock We are offering 5,250,000 shares of our common stock, par value $0.001 per share. Our common stock is listed on The Nasdaq Global Select Market under the symbol “KLDO.” On February 3, 2021, the last reported sale price of our

February 3, 2021 424B5

$50,000,000 Common Stock

424B5 Table of Contents Filed Pursuant to Rule 424(b)(5) Registration No. 333-420323 The information in this preliminary prospectus supplement and the accompanying prospectus is not complete and may be changed. A registration statement relating to the securities has been declared effective by the Securities and Exchange Commission. This preliminary prospectus supplement and accompanying prospectus

January 25, 2021 EX-10.1

Separation Agreement, dated January 25, 2021, by and between Kaleido Biosciences, Inc. and Katharine Knobil.

Exhibit 10.1 KALEIDO BIOSCIENCES Consulting and Separation Agreement This Consulting and Separation Agreement (the “Agreement”), made as of January 25, 2021 is entered into by Kaleido BioSciences, Inc., a Delaware corporation with offices at 65 Hayden Aveenue, Lexington MA 02421 (the “Company”), and Katharine Knobil, M.D. an individual residing in Pennsylvania (the “Consultant”). WHEREAS, Consulta

January 25, 2021 8-K

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Financial Statements and Exhibits - 8-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): January 20, 2021 KALEIDO BIOSCIENCES, INC. (Exact name of registrant as specified in its charter) Delaware 001-38822 47-3048279 (State or other jurisdiction of incorporation) (Commiss

January 20, 2021 EX-99.1

Forward-Looking Statements This presentation also contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended, including, without limitation, statements regarding our strategy, business p

Leading a Novel Approach to Targeting the Microbiome NASDAQ: KLDO January 2021 Exhibit 99.

January 20, 2021 8-K/A

Financial Statements and Exhibits, Other Events - 8-K/A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K/A (Amendment No. 1) CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): January 19, 2021 KALEIDO BIOSCIENCES, INC. (Exact name of registrant as specified in its charter) Delaware 001-38822 47-3048279 (State or other jurisdiction of inc

January 19, 2021 8-K

Financial Statements and Exhibits, Other Events - 8-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): January 19, 2021 KALEIDO BIOSCIENCES, INC. (Exact name of registrant as specified in its charter) Delaware 001-38822 47-3048279 (State or other jurisdiction of incorporation) (Commiss

January 19, 2021 EX-99.1

Forward-Looking Statements This presentation also contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended, including, without limitation, statements regarding our strategy, business p

Leading a Novel Approach to Targeting the Microbiome NASDAQ: KLDO January 2021 Exhibit 99.

January 14, 2021 EX-99.1

Forward-Looking Statements This presentation also contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended, including, without limitation, statements regarding our strategy, business p

Leading a Novel Approach to Targeting the Microbiome NASDAQ: KLDO January 2021 Exhibit 99.

January 14, 2021 8-K

Regulation FD Disclosure, Financial Statements and Exhibits, Other Events

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): January 14, 2021 KALEIDO BIOSCIENCES, INC. (Exact name of registrant as specified in its charter) Delaware 001-38822 47-3048279 (State or other jurisdiction of incorporation) (Commiss

January 14, 2021 EX-99.2

Kaleido Biosciences Announces Positive Interim Results of Controlled Study of KB109 in Patients with Mild-to-Moderate COVID-19 Preliminary analysis (n=176) demonstrates favorable safety and tolerability; data provide a strong signal of clinical benef

Exhibit 99.2 Kaleido Biosciences Announces Positive Interim Results of Controlled Study of KB109 in Patients with Mild-to-Moderate COVID-19 Preliminary analysis (n=176) demonstrates favorable safety and tolerability; data provide a strong signal of clinical benefit for subjects reporting one or more comorbidities Topline data from full study population of 350 patients and results of second study o

November 2, 2020 EX-99.1

Kaleido Biosciences Reports Third Quarter 2020 Financial Results and Provides Corporate Update - Topline Data for KB109 for the Treatment of Mild-to-Moderate COVID-19 Expected in the First Quarter of 2021 -

Exhibit 99.1 Kaleido Biosciences Reports Third Quarter 2020 Financial Results and Provides Corporate Update - Topline Data for KB109 for the Treatment of Mild-to-Moderate COVID-19 Expected in the First Quarter of 2021 - LEXINGTON, Mass., November 2, 2020 – Kaleido Biosciences, Inc. (Nasdaq: KLDO) today announced financial results for the third quarter 2020 and provided a corporate update. “Kaleido

November 2, 2020 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition - 8-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): November 2, 2020 KALEIDO BIOSCIENCES, INC. (Exact name of registrant as specified in its charter) Delaware 001-38822 47-3048279 (State or other jurisdiction of incorporation) (Commiss

November 2, 2020 10-Q

Quarterly Report - 10-Q

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended September 30, 2020 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-3882

October 13, 2020 8-K

- 8-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): October 9, 2020 KALEIDO BIOSCIENCES, INC. (Exact name of registrant as specified in its charter) Delaware 001-38822 47-3048279 (State or other jurisdiction of incorporation) (Commissi

October 1, 2020 8-K

Regulation FD Disclosure, Financial Statements and Exhibits - 8-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): September 29, 2020 KALEIDO BIOSCIENCES, INC. (Exact name of registrant as specified in its charter) Delaware 001-38822 47-3048279 (State or other jurisdiction of incorporation) (Commi

October 1, 2020 EX-10.1

Employment Agreement, dated September 30, 2020, by and between Kaleido Biosciences, Inc. and Daniel Menichella.

Exhibit 10.1 kALEIDO BIOSCIENCES, INC. EMPLOYMENT AGREEMENT This Employment Agreement (“Agreement”) is made as of September 30, 2020, between Kaleido Biosciences, Inc., a Delaware corporation (the “Company”), and Daniel Menichella (the “Employee”) and is effective as October 13, 2020 (the “Effective Date”). In consideration of the mutual covenants and agreements herein contained and other good and

October 1, 2020 EX-99.1

Kaleido Biosciences Appoints Daniel Menichella as President and Chief Executive Officer

Exhibit 99.1 Kaleido Biosciences Appoints Daniel Menichella as President and Chief Executive Officer LEXINGTON, Mass., October 1, 2020 – Kaleido Biosciences, Inc. (Nasdaq: KLDO), a clinical-stage healthcare company with a chemistry-driven approach to targeting the microbiome to treat disease and improve human health, announced that Daniel Menichella has been appointed President and Chief Executive

August 12, 2020 CORRESP

-

CORRESP Kaleido Biosciences, Inc. 65 Hayden Avenue Lexington, MA 02421 August 12, 2020 Via EDGAR Transmission United States Securities and Exchange Commission Division of Corporation Finance 100 F Street, N.E. Washington, D.C. 20549 Re: Kaleido Biosciences, Inc.: Registration Statement on Form S-3 filed August 4, 2020 (File No. 333-240323) Ladies and Gentlemen: Pursuant to Rule 461 under the Secur

August 4, 2020 10-Q

Quarterly Report - 10-Q

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2020 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-38822 KAL

August 4, 2020 EX-1.2

Equity Distribution Agreement, dated as of August 4, 2020 by and between Kaleido Biosciences, Inc. and Piper Sandler & Co.

EX-1.2 Exhibit 1.2 KALEIDO BIOSCIENCES, INC. EQUITY DISTRIBUTION AGREEMENT August 4, 2020 PIPER SANDLER & CO. U.S. Bancorp Center 800 Nicollet Mall Minneapolis, Minnesota 55402 Ladies and Gentlemen: As further set forth in this agreement (this “Agreement”), Kaleido Biosciences, Inc., a Delaware corporation (the “Company”), proposes to issue and sell from time to time through Piper Sandler & Co. (t

August 4, 2020 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): August 4, 2020 KALEIDO BIOSCIENCES, INC. (Exact name of registrant as specified in its charter) Delaware 001-38822 47-3048279 (State or other jurisdiction of incorporation) (Commissio

August 4, 2020 EX-99.1

Kaleido Biosciences Reports Second Quarter 2020 Financial Results and Provides Corporate Update - COVID-19 Clinical Development Program Topline Data Readout of Multi-Center Study Expected in Q4 2020 - - Plan to Initiate New Clinical Study in Ulcerati

Exhibit 99.1 Kaleido Biosciences Reports Second Quarter 2020 Financial Results and Provides Corporate Update - COVID-19 Clinical Development Program Topline Data Readout of Multi-Center Study Expected in Q4 2020 - - Plan to Initiate New Clinical Study in Ulcerative Colitis in Q3 2020 - LEXINGTON, Mass., August 4, 2020 – Kaleido Biosciences, Inc. (Nasdaq: KLDO), a clinical-stage healthcare company

August 4, 2020 EX-4.3

Form of indenture for senior debt securities and the related form of senior debt security

EX-4.3 Exhibit 4.3 KALEIDO BIOSCIENCES, INC., Issuer AND [TRUSTEE], Trustee INDENTURE Dated as of [ ], 202[ ] Senior Debt Securities TABLE OF CONTENTS1 ARTICLE 1 DEFINITIONS 1 Section 1.01 Definitions of Terms 1 ARTICLE 2 ISSUE, DESCRIPTION, TERMS, EXECUTION, REGISTRATION AND EXCHANGE OF SECURITIES 5 Section 2.01 Designation and Terms of Securities 5 Section 2.02 Form of Securities and Trustee’s C

August 4, 2020 EX-4.4

Form of indenture for subordinated debt securities and the related form of subordinated debt security

EX-4.4 Exhibit 4.4 KALEIDO BIOSCIENCES, INC., Issuer AND [TRUSTEE], Trustee INDENTURE Dated as of [ ], 202[ ] Subordinated Debt Securities TABLE OF CONTENTS1 ARTICLE 1 DEFINITIONS 1 Section 1.01 Definitions of Terms 1 ARTICLE 2 ISSUE, DESCRIPTION, TERMS, EXECUTION, REGISTRATION AND EXCHANGE OF SECURITIES 5 Section 2.01 Designation and Terms of Securities 5 Section 2.02 Form of Securities and Trust

August 4, 2020 S-3

Registration Statement No. 333-240323, filed on August 4, 2020.

S-3 Table of Contents As filed with the Securities and Exchange Commission on August 4, 2020.

July 23, 2020 EX-10.1

Amendment to Lawton Employment Agreement

Exhibit 10.1 AMENDMENT TO EMPLOYMENT AGREEMENT This Amendment to Employment Agreement (the “Amendment”) is by and between Kaleido Biosciences, Inc. (the “Company”) and Alison Lawton (the “Employee”) and is made effective as of July 20, 2020 (the “Effective Date”). WHEREAS, the Company and the Employee are parties to an Employment Agreement dated as of January 24, 2019 (the “Employment Agreement”);

July 23, 2020 8-K

Financial Statements and Exhibits

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): July 20, 2020 KALEIDO BIOSCIENCES, INC. (Exact name of registrant as specified in its charter) Delaware 001-38822 47-3048279 (State or other jurisdiction of incorporation) (Commission

June 18, 2020 EX-10.1

Second Amendment to Loan and Security Agreement, dated June 15, 2020, by and among Kaleido Biosciences, Inc. and each of its Qualified Subsidiaries (including Cadena Bio, Inc.), the several banks and other financial institutions or entities from time to time parties to the Loan Agreement and Hercules Capital, Inc. †

Exhibit 10.1 CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED BY [***], HAS BEEN OMITTED BECAUSE IT IS NOT MATERIAL AND WOULD LIKELY CAUSE COMPETITIVE HARM TO THE COMPANY IF PUBLICLY DISCLOSED. SECOND AMENDMENT TO LOAN AND SECURITY AGREEMENT THIS SECOND AMENDMENT TO LOAN AND SECURITY AGREEMENT (this “Amendment”), dated as of June 15, 2020 (the “Amendment Effective Date”), is mad

June 18, 2020 8-K

Financial Statements and Exhibits, Submission of Matters to a Vote of Security Holders

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): June 15, 2020 KALEIDO BIOSCIENCES, INC. (Exact name of registrant as specified in its charter) Delaware 001-38822 47-3048279 (State or other jurisdiction of incorporation) (Commission

June 16, 2020 EX-99.1

Kaleido Biosciences Announces CEO Leadership Transition - Alison Lawton to step down as President and Chief Executive Officer to attend to a family health matter - The Board of Directors has established an Office of the CEO to manage the company thro

Exhibit 99.1 Kaleido Biosciences Announces CEO Leadership Transition - Alison Lawton to step down as President and Chief Executive Officer to attend to a family health matter - The Board of Directors has established an Office of the CEO to manage the company through the transition, with Mike Bonney, Executive Chair, to lead the office and Alison Lawton to serve as a special advisor LEXINGTON, Mass

June 16, 2020 8-K

Financial Statements and Exhibits

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): June 14, 2020 KALEIDO BIOSCIENCES, INC. (Exact name of registrant as specified in its charter) Delaware 001-38822 47-3048279 (State or other jurisdiction of incorporation) (Commission

June 8, 2020 EX-99.1

JOINT FILING AGREEMENT

Exhibit 1 Exhibit 1 JOINT FILING AGREEMENT The persons below hereby agree that the Schedule 13D to which this agreement is attached as an exhibit, as well as all future amendments to such Schedule 13D, shall be filed jointly on behalf of each of them.

June 8, 2020 SC 13D/A

KLDO / Kaleido Biosciences, Inc. / Flagship Ventures Fund V, L.p. - SCHEDULE 13D/A Activist Investment

Schedule 13D/A SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13D Under the Securities Exchange Act of 1934 (Amendment No. 1)* Kaleido Biosciences, Inc. (Name of Issuer) Common Stock, par value $0.001 per share (Title of Class of Securities) 483347100 (CUSIP Number) Noubar B. Afeyan, Ph.D. Flagship Ventures 55 Cambridge Parkway, Suite 800E Cambridge, MA 02142 (617) 868-1888 (Na

June 4, 2020 8-K

Entry into a Material Definitive Agreement, Financial Statements and Exhibits, Other Events

8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): June 1, 2020 KALEIDO BIOSCIENCES, INC. (Exact name of registrant as specified in its charter) Delaware 001-38822 47-3048279 (State or other jurisdiction of incorporation) (Commiss

June 4, 2020 EX-99.2

Kaleido Biosciences Announces Pricing of Public Offering of Common Stock

EX-99.2 Exhibit 99.2 Kaleido Biosciences Announces Pricing of Public Offering of Common Stock LEXINGTON, Mass., June 1, 2020 – Kaleido Biosciences, Inc. (Nasdaq: KLDO), a clinical-stage healthcare company with a chemistry-driven approach to targeting the microbiome to treat disease and improve human health, today announced the pricing of an underwritten public offering of 4,750,000 shares of its c

June 4, 2020 EX-99.1

Kaleido Biosciences Announces Proposed Public Offering of Common Stock

EX-99.1 Exhibit 99.1 Kaleido Biosciences Announces Proposed Public Offering of Common Stock LEXINGTON, Mass., June 1, 2020 – Kaleido Biosciences, Inc. (Nasdaq: KLDO), a clinical-stage healthcare company with a chemistry-driven approach to targeting the microbiome to treat disease and improve human health, today announced that it intends to sell, subject to market and other conditions, $30 million

June 4, 2020 EX-1.1

Underwriting Agreement, dated June 1, 2020, by and between Kaleido Biosciences, Inc. and Morgan Stanley & Co. LLC.

EX-1.1 Exhibit 1.1 KALEIDO BIOSCIENCES, INC. 4,750,000 Shares of Common Stock Underwriting Agreement June 1, 2020 Morgan Stanley & Co. LLC As Representative of the several Underwriters listed in Schedule 1 hereto c/o Morgan Stanley & Co. LLC 1585 Broadway New York, New York 10036 Ladies and Gentlemen: Kaleido Biosciences, Inc., a Delaware corporation (the “Company”), proposes to issue and sell to

June 3, 2020 424B5

4,750,000 Shares Common Stock

424B5 Table of Contents Filed Pursuant to Rule 424(b)(5) Registration No. 333-236804 PROSPECTUS SUPPLEMENT (to Prospectus dated March 10, 2020) 4,750,000 Shares Common Stock We are offering 4,750,000 shares of our common stock, par value $0.001 per share. Our common stock is listed on The Nasdaq Global Select Market under the symbol “KLDO.” On June 1, 2020, the last reported sale price of our comm

June 1, 2020 424B5

$30,000,000 Common Stock

424B5 Table of Contents Filed Pursuant to Rule 424(b)(5) Registration No. 333-236804 The information in this preliminary prospectus supplement and the accompanying prospectus is not complete and may be changed. A registration statement relating to the securities has been declared effective by the Securities and Exchange Commission. This preliminary prospectus supplement and accompanying prospectus

May 14, 2020 EX-99.1

Kaleido Biosciences Provides Corporate Update and Reports First Quarter 2020 Financial Results - Initiating Clinical Studies of KB109 in Outpatients with Mild-to-Moderate COVID-19; Data Anticipated in Q4 2020 - - Expanding Work in Immune-Mediated and

Exhibit 99.1 Kaleido Biosciences Provides Corporate Update and Reports First Quarter 2020 Financial Results - Initiating Clinical Studies of KB109 in Outpatients with Mild-to-Moderate COVID-19; Data Anticipated in Q4 2020 - - Expanding Work in Immune-Mediated and Inflammatory Diseases; Data from New Clinical Study in Ulcerative Colitis Expected in Mid-2021 - - Conference Call Scheduled for 8:30 a.

May 14, 2020 EX-99.2

1 ©2020 KALEIDO™ ©2020 KALEIDO™ Company Overview May 2020

Exhibit 99.2 1 ©2020 KALEIDO™ ©2020 KALEIDO™ Company Overview May 2020 2 ©2020 KALEIDO™ Forward - Looking Statements This presentation also contains forward - looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended, including, without limitation, statements regarding our strategy, business plans and focus, including the therapeutic potential of our

May 14, 2020 8-K

Regulation FD Disclosure, Financial Statements and Exhibits, Results of Operations and Financial Condition, Other Events

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 14, 2020 KALEIDO BIOSCIENCES, INC. (Exact name of registrant as specified in its charter) Delaware 001-38822 47-3048279 (State or other jurisdiction of incorporation) (Commission

May 14, 2020 EX-99.3

Kaleido Biosciences Initiates Controlled Clinical Study of Microbiome Metabolic Therapy KB109 in Outpatients with Mild-to-Moderate COVID-19 - Top-Line Data from Study of Approximately 350 Patients Expected in Q4 2020 - - Second Clinical Study Expecte

Exhibit 99.3 Kaleido Biosciences Initiates Controlled Clinical Study of Microbiome Metabolic Therapy KB109 in Outpatients with Mild-to-Moderate COVID-19 - Top-Line Data from Study of Approximately 350 Patients Expected in Q4 2020 - - Second Clinical Study Expected to Initiate Shortly with Similar Design and Additional Microbiome Analysis - LEXINGTON, Mass., May 14, 2020 – Kaleido Biosciences, Inc.

May 14, 2020 10-Q

Quarterly Report - 10-Q

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2020 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-38822 KA

May 8, 2020 DEFA14A

- DEFA14A

DEFA14A UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A (Rule 14a-101) Information Required in Proxy Statement Schedule 14A Information Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 Filed by the Registrant ☒ Filed by a Party other than the Registrant ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, fo

May 8, 2020 S-8

No. 333-238123

S-8 Table of Contents As filed with the Securities and Exchange Commission on May 8, 2020 Registration No.

May 8, 2020 EX-3.1

Amendment to Amended and Restated By-laws of the Registrant, dated May 7, 2020 (Incorporated by reference to Exhibit 3.1 on Registrant’s Current Report on Form 8-K filed on May 8, 2020)

EX-3.1 Exhibit 3.1 AMENDMENT TO THE AMENDED AND RESTATED BY-LAWS Section 8 of Article VI of the Amended and Restated By-laws of Kaleido Biosciences, Inc. (the “By-laws”), is hereby amended and restated in its entirety to read as follows: “SECTION 8. Exclusive Jurisdiction. Unless the Corporation consents in writing to the selection of an alternative forum, the Court of Chancery of the State of Del

May 8, 2020 DEF 14A

Schedule 14A

DEF 14A Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.

May 8, 2020 8-K

Amendments to Articles of Incorporation or Bylaws; Change in Fiscal Year, Financial Statements and Exhibits

8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 7, 2020 KALEIDO BIOSCIENCES, INC. (Exact name of registrant as specified in its charter) Delaware 001-38822 47-3048279 (State or other jurisdiction of incorporation) (Commissi

April 3, 2020 EX-99.1

Kaleido Biosciences Appoints Anne Prener, M.D., Ph.D., to its Board of Directors

EX-99.1 Exhibit 99.1 Kaleido Biosciences Appoints Anne Prener, M.D., Ph.D., to its Board of Directors LEXINGTON, Mass., April 3, 2020 – Kaleido Biosciences, Inc. (Nasdaq: KLDO), a clinical-stage healthcare company with a chemistry-driven approach to leveraging the microbiome organ to treat disease and improve human health, today announced the appointment of Anne Prener, M.D., Ph.D., to its Board o

April 3, 2020 8-K

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Financial Statements and Exhibits

8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): April 1, 2020 KALEIDO BIOSCIENCES, INC. (Exact name of registrant as specified in its charter) Delaware 001-38822 47-3048279 (State or other jurisdiction of incorporation) (Commis

March 6, 2020 CORRESP

KLDO / Kaleido Biosciences, Inc. CORRESP - -

CORRESP Kaleido Biosciences, Inc. 65 Hayden Avenue Lexington, MA 02421 March 6, 2020 Via EDGAR Transmission United States Securities and Exchange Commission Division of Corporation Finance 100 F Street, N.E. Washington, D.C. 20549 Re: Kaleido Biosciences, Inc.: Registration Statement on Form S-3 filed March 2, 2020 (File No. 333-236804) Ladies and Gentlemen: Pursuant to Rule 461 under the Securiti

March 2, 2020 S-3

KLDO / Kaleido Biosciences, Inc. S-3 - - S-3

S-3 Table of Contents As filed with the Securities and Exchange Commission on March 2, 2020.

March 2, 2020 EX-4.3

Exhibit 4.3

Exhibit 4.3 Description of the Registrant’s Securities Registered Pursuant to Section 12 of the Securities Exchange Act of 1934, as amended The summary of the general terms and provisions of the registered securities of Kaleido Biosciences, Inc. (“Kaleido” “we,” or “our”) set forth below does not purport to be complete and is subject to and qualified in its entirety by reference to our Amended and

March 2, 2020 EX-10.13

Employment Agreement between the Registrant and William Duke, Jr., dated December 2, 2019 (incorporated by reference to Exhibit 10.13 to the Registrant’s Annual Report on Form 10-K (File No. 001-38822) filed on March 2, 2020).

Exhibit 10.13 KALEIDO BIOSCIENCES, INC. EMPLOYMENT AGREEMENT This Employment Agreement (“Agreement”) is made on or before December 2, 2019, between Kaleido Biosciences, Inc., a Delaware corporation (the “Company”), and William Duke (the “Employee”) and is effective as of the date executed by the parties hereto (the “Effective Date”). In consideration of the mutual covenants and agreements herein c

March 2, 2020 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition

8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): March 2, 2020 KALEIDO BIOSCIENCES, INC. (Exact name of registrant as specified in its charter) Delaware 001-38822 47-3048279 (State or other jurisdiction of incorporation) (Commis

March 2, 2020 EX-99.1

Kaleido Biosciences Reports Fourth Quarter and Full Year 2019 Financial Results and Provides Corporate Update

EX-99.1 Exhibit 99.1 Kaleido Biosciences Reports Fourth Quarter and Full Year 2019 Financial Results and Provides Corporate Update - Results from three clinical studies in 2019 support Phase 2 development program in urea cycle disorders (UCD) and advancement of hepatic encephalopathy program into next clinical study - Top-line data expected in Q4 2020 from Phase 2 trial of KB195 in patients with U

March 2, 2020 EX-4.4

Form of indenture for subordinated debt securities and the related form of subordinated debt security

EX-4.4 Exhibit 4.4 KALEIDO BIOSCIENCES, INC., Issuer AND [TRUSTEE], Trustee INDENTURE Dated as of [ ], 202[ ] Subordinated Debt Securities TABLE OF CONTENTS1 ARTICLE 1 DEFINITIONS 1 Section 1.01 Definitions of Terms 1 ARTICLE 2 ISSUE, DESCRIPTION, TERMS, EXECUTION, REGISTRATION AND EXCHANGE OF SECURITIES 5 Section 2.01 Designation and Terms of Securities 5 Section 2.02 Form of Securities and Trust

March 2, 2020 10-K

Annual Report - 10-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K ☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2019 or ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-38822 KALEIDO BIOSCIENCES, INC.

March 2, 2020 EX-21.1

Subsidiaries of the Registrant

Exhibit 21.1 SUBSIDIARIES Subsidiary Jurisdiction of Incorporation Cadena Bio, Inc. Delaware Kaleido Biosciences Securities Corporation Massachusetts

March 2, 2020 EX-4.3

Form of indenture for senior debt securities and the related form of senior debt security

EX-4.3 Exhibit 4.3 KALEIDO BIOSCIENCES, INC., Issuer AND [TRUSTEE], Trustee INDENTURE Dated as of [ ], 202[ ] Senior Debt Securities TABLE OF CONTENTS1 ARTICLE 1 DEFINITIONS 1 Section 1.01 Definitions of Terms 1 ARTICLE 2 ISSUE, DESCRIPTION, TERMS, EXECUTION, REGISTRATION AND EXCHANGE OF SECURITIES 5 Section 2.01 Designation and Terms of Securities 5 Section 2.02 Form of Securities and Trustee’s C

January 7, 2020 8-K

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers

8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): January 6, 2020 KALEIDO BIOSCIENCES, INC. (Exact name of registrant as specified in its charter) Delaware 001-38822 47-3048279 (State or other jurisdiction of incorporation) (Comm

January 3, 2020 8-K

Entry into a Material Definitive Agreement, Termination of a Material Definitive Agreement, Financial Statements and Exhibits, Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant

8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): December 31, 2019 KALEIDO BIOSCIENCES, INC. (Exact name of registrant as specified in its charter) Delaware 001-38822 47-3048279 (State or other jurisdiction of incorporation) (Co

January 3, 2020 EX-10.1

Credit Agreement, dated December 31, 2019, by and among Kaleido Biosciences, Inc., Cadena Bio, Inc. and Hercules Capital, Inc. †

EX-10.1 Exhibit 10.1 CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED BY [***], HAS BEEN OMITTED BECAUSE IT IS NOT MATERIAL AND WOULD LIKELY CAUSE COMPETITIVE HARM TO THE COMPANY IF PUBLICLY DISCLOSED. LOAN AND SECURITY AGREEMENT THIS LOAN AND SECURITY AGREEMENT is made and dated as of December 31, 2019 and is entered into by and among KALEIDO BIOSCIENCES, INC., a Delaware corpo

December 12, 2019 8-K

Regulation FD Disclosure, Financial Statements and Exhibits

8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): December 12, 2019 KALEIDO BIOSCIENCES, INC. (Exact name of registrant as specified in its charter) Delaware 001-38822 47-3048279 (State or other jurisdiction of incorporation) (Co

December 12, 2019 EX-99.1

Kaleido Biosciences to Advance KB174 for Hepatic Encephalopathy Based on Positive Top-Line Results from a Clinical Study in Patients with Cirrhosis

EX-99.1 Exhibit 99.1 Kaleido Biosciences to Advance KB174 for Hepatic Encephalopathy Based on Positive Top-Line Results from a Clinical Study in Patients with Cirrhosis - KB174 Exceeded the Targeted Reduction in a Biomarker of Microbiome Ammonia Production - KB174 Was Well Tolerated and No Clinically Significant or Serious Treatment-Related Adverse Events Were Observed LEXINGTON, Mass., December 1

December 12, 2019 EX-99.2

Forward-Looking Statements This presentation contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended, including, without limitation, statements regarding the anticipated use of our ex

EX-99.2 Exhibit 99.2 Company Overview December 2019 1 ©2 ©201 019 K 9 KA ALE LEIDO IDO™ ™Exhibit 99.2 Company Overview December 2019 1 ©2 ©201 019 K 9 KA ALE LEIDO IDO™ ™ Forward-Looking Statements This presentation contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended, including, without limitation, statements regarding the anti

November 6, 2019 EX-99.1

Kaleido Biosciences Appoints William Duke as Chief Financial Officer

EX-99.1 Exhibit 99.1 Kaleido Biosciences Appoints William Duke as Chief Financial Officer LEXINGTON, Mass., November 6, 2019 – Kaleido Biosciences, Inc. (Nasdaq: KLDO), a clinical-stage healthcare company with a chemistry-driven approach to leveraging the microbiome organ to treat disease and improve human health, today announced the appointment of William Duke as Chief Financial Officer (CFO), ef

November 6, 2019 8-K

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Financial Statements and Exhibits

8-K 1 d821616d8k.htm 8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): November 4, 2019 KALEIDO BIOSCIENCES, INC. (Exact name of registrant as specified in its charter) Delaware 001-38822 47-3048279 (State or other jurisdiction o

October 30, 2019 8-K

Entry into a Material Definitive Agreement, Termination of a Material Definitive Agreement, Financial Statements and Exhibits, Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant

8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): October 25, 2019 KALEIDO BIOSCIENCES, INC. (Exact name of registrant as specified in its charter) Delaware 001-38822 47-3048279 (State or other jurisdiction of incorporation) (Com

October 30, 2019 EX-10.1

Credit Agreement, dated October 25, 2019, by and among Kaleido Biosciences, Inc., Cadena Bio, Inc. and JPMorgan Chase Bank, N.A.†

EX-10.1 Exhibit 10.1 CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED BY [***], HAS BEEN OMITTED BECAUSE IT IS NOT MATERIAL AND WOULD LIKELY CAUSE COMPETITIVE HARM TO THE COMPANY IF PUBLICLY DISCLOSED. Execution Version CREDIT AGREEMENT dated as of October 25, 2019, by and among KALEIDO BIOSCIENCES, INC., CADENA BIO, INC., and JPMORGAN CHASE BANK, N.A. CREDIT AGREEMENT dated as

October 30, 2019 8-K

Regulation FD Disclosure, Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): October 30, 2019 KALEIDO BIOSCIENCES, INC. (Exact name of registrant as specified in its charter) Delaware 001-38822 47-3048279 (State or other jurisdiction of incorporation) (Commiss

October 30, 2019 EX-99.2

Company Overview October 30, 2019 1 ©2019 KALEIDO™ Forward-Looking Statements This presentation contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended, including, without limitation,

kaleidooverview103019 Company Overview October 30, 2019 1 ©2019 KALEIDO™ Forward-Looking Statements This presentation contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended, including, without limitation, statements regarding the anticipated use of our existing cash resources, the duration for which our existing capital resources will fund our operations, the therapeutic potential of our Microbiome Metabolic Therapy (MMT) candidates, the timing of initiation, completion and reporting of results of our clinical studies and our strategy, business plans and focus.

October 30, 2019 EX-99.1

Kaleido Biosciences Reports Third Quarter 2019 Financial Results and Provides Corporate Update –Executing Pipeline Towards Key Clinical Data Readouts in Q4 2019 and 2020 –Focusing Resources on Pipeline Programs and Extending Cash Runway

Exhibit 99.1 Kaleido Biosciences Reports Third Quarter 2019 Financial Results and Provides Corporate Update –Executing Pipeline Towards Key Clinical Data Readouts in Q4 2019 and 2020 –Focusing Resources on Pipeline Programs and Extending Cash Runway LEXINGTON, Mass., October 30, 2019 – Kaleido Biosciences, Inc. (Nasdaq: KLDO), a clinical-stage healthcare company with a chemistry-driven approach to

October 30, 2019 10-Q

Quarterly Report - 10-Q

Table of Contents 

 UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.

October 30, 2019 EX-10.1

Consulting Agreement between the Registrant and Joshua Brumm, dated September 26, 2019 (incorporated by reference to Exhibit 10.1 to the Registrants Quarterly Report on Form 10-Q (File No. 001-38822) filed on October 30, 2019).

Exhibit 10.1 KALEIDO BIOSCIENCES Consulting and Separation Agreement This Consulting and Separation Agreement (the “Agreement”), made as of the 26th day of September, 2019 is entered into by Kaleido BioSciences, Inc., a Delaware corporation with offices at 18 Crosby Drive, Bedford, MA 01730 (the “Company”), and Joshua Brumm, an individual residing in Wellesley, MA (the “Consultant”). WHEREAS, Cons

September 30, 2019 8-K

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Financial Statements and Exhibits

8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): September 25, 2019 KALEIDO BIOSCIENCES, INC. (Exact name of registrant as specified in its charter) Delaware 001-38822 47-3048279 (State or other jurisdiction of incorporation) (C

September 30, 2019 EX-99.1

Kaleido Biosciences Announces Appointment of Jean Mixer to its Board of Directors

EX-99.1 Exhibit 99.1 Kaleido Biosciences Announces Appointment of Jean Mixer to its Board of Directors LEXINGTON, Mass., Sept. 30, 2019 – Kaleido Biosciences, Inc. (Nasdaq: KLDO), a clinical-stage healthcare company with a chemistry-driven approach to leveraging the microbiome organ to treat disease and improve human health, today announced that Jean Mixer has been appointed to its Board of Direct

September 26, 2019 EX-99.1

Kaleido Biosciences Announces CFO Transition

EX-99.1 Exhibit 99.1 Kaleido Biosciences Announces CFO Transition LEXINGTON, Mass., Sept. 26, 2019 – Kaleido Biosciences, Inc. (Nasdaq: KLDO), a clinical-stage healthcare company with a chemistry-driven approach to leveraging the microbiome organ to treat disease and improve human health, today announced that Joshua Brumm will step down as Chief Operating and Chief Financial Officer effective Octo

September 26, 2019 8-K

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Financial Statements and Exhibits

Form 8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): September 23, 2019 KALEIDO BIOSCIENCES, INC. (Exact name of registrant as specified in its charter) Delaware 001-38822 47-3048279 (State or other jurisdiction of incorporatio

August 1, 2019 EX-99.2

Company Overview AUGUST 2019 | ⓒ 2019 KALEIDO™ Forward-Looking Statements This presentation contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended, including, without limitation, sta

kaleidooverviewaugust201 Company Overview AUGUST 2019 | ⓒ 2019 KALEIDO™ Forward-Looking Statements This presentation contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended, including, without limitation, statements regarding the anticipated use of our existing cash resources, including proceeds from our initial public offering, the duration for which our existing capital resources will fund our operations, statements regarding the therapeutic potential of our Microbiome Metabolic Therapy (MMT) candidates and our strategy, business plans and focus.

August 1, 2019 8-K

Regulation FD Disclosure, Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): August 1, 2019 KALEIDO BIOSCIENCES, INC. (Exact name of registrant as specified in its charter) Delaware 001-38822 47-3048279 (State or other jurisdiction of incorporation) (Commissio

August 1, 2019 EX-99.1

Kaleido Biosciences Reports Second Quarter 2019 Financial Results and Provides Corporate Update

Exhibit 99.1 Kaleido Biosciences Reports Second Quarter 2019 Financial Results and Provides Corporate Update LEXINGTON, Mass., August 1, 2019 - Kaleido Biosciences, Inc. (Nasdaq: KLDO), a clinical-stage healthcare company with a chemistry-driven approach to leveraging the potential of the microbiome organ to treat disease and improve human health, today announced financial results for the second q

August 1, 2019 10-Q

Quarterly Report - 10-Q

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q x QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2019 or ¨ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-38822 KAL

July 15, 2019 EX-99.1

Kaleido Biosciences Announces Appointment of Theo Melas-Kyriazi to its Board of Directors

EX-99.1 EXHIBIT 99.1 Kaleido Biosciences Announces Appointment of Theo Melas-Kyriazi to its Board of Directors LEXINGTON, Mass., July 15, 2019 – Kaleido Biosciences, Inc. (Nasdaq: KLDO), a clinical-stage healthcare company with a chemistry-driven approach to leveraging the potential of the microbiome organ to treat disease and improve human health, today announced that Theo Melas-Kyriazi, Executiv

July 15, 2019 8-K

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Financial Statements and Exhibits

8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): July 10, 2019 KALEIDO BIOSCIENCES, INC. (Exact name of registrant as specified in its charter) Delaware 001-38822 47-3048279 (State or other jurisdiction of incorporation) (Commis

May 2, 2019 EX-99.1

Kaleido Biosciences Reports First Quarter 2019 Financial Results and Provides Corporate Update

Exhibit 99.1 Kaleido Biosciences Reports First Quarter 2019 Financial Results and Provides Corporate Update LEXINGTON, Mass., May 2, 2019 – Kaleido Biosciences, Inc. (Nasdaq: KLDO), a clinical-stage healthcare company with a differentiated, chemistry-driven approach to leveraging the potential of the microbiome organ to treat disease and improve human health, today announced financial results for

May 2, 2019 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 2, 2019 KALEIDO BIOSCIENCES, INC. (Exact name of registrant as specified in its charter) Delaware 001-38822 47-3048279 (State or other jurisdiction of incorporation) (Commission F

May 2, 2019 10-Q

KLDO / Kaleido Biosciences, Inc. 10-Q Quarterly Report 10-Q

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q x QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2019 or ¨ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-38822 KA

April 8, 2019 EX-99.1

Forward-Looking Statements This presentation contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended, including, without limitation, statements regarding the anticipated use of our ex

EX-99.1 APRIL 2019 Company Overview Exhibit 99.1 Forward-Looking Statements This presentation contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended, including, without limitation, statements regarding the anticipated use of our existing cash resources, including proceeds from our initial public offering, the duration for which ou

April 8, 2019 8-K

Regulation FD Disclosure, Financial Statements and Exhibits

Form 8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of Earliest Event Reported): April 8, 2019 Kaleido Biosciences, Inc. (Exact name of registrant as specified in its charter) Delaware 001-38822 47-3048279 (State or other jurisdiction of incorporation) (C

March 18, 2019 8-K

Entry into a Material Definitive Agreement

Form 8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event Reported): March 13, 2019 Kaleido Biosciences, Inc. (Exact Name of Registrant as Specified in Charter) Delaware 001-38822 47-3048279 (State or Other Jurisdiction of Incorporation) (Comm

March 8, 2019 S-8

No. 333-230167

S-8 As filed with the Securities and Exchange Commission on March 8, 2019 Registration No.

March 6, 2019 EX-99.1

JOINT FILING AGREEMENT

Exhibit 1 Exhibit 1 JOINT FILING AGREEMENT The persons below hereby agree that the Schedule 13D to which this agreement is attached as an exhibit, as well as all future amendments to such Schedule 13D, shall be filed jointly on behalf of each of them.

March 6, 2019 SC 13D

KLDO / Kaleido Biosciences, Inc. / Flagship Ventures Fund V, L.p. - SCHEDULE 13D Activist Investment

Schedule 13D SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13D Under the Securities Exchange Act of 1934 (Amendment )* Kaleido Biosciences, Inc. (Name of Issuer) Common Stock, par value $0.001 per share (Title of Class of Securities) 483347100 (CUSIP Number) Noubar B. Afeyan, Ph.D. Flagship Ventures 55 Cambridge Parkway, Suite 800E Cambridge, MA 02142 (617) 868-1888 (Name, Add

March 4, 2019 EX-3.2

Amended and Restated Bylaws of Kaleido Biosciences, Inc. (Incorporated by reference to Exhibit 3.2 to the Registrant’s Current Report on Form 8-K filed on March 4, 2019)

EX-3.2 Exhibit 3.2 AMENDED AND RESTATED BY-LAWS OF KALEIDO BIOSCIENCES, INC. (the “Corporation”) ARTICLE I Stockholders SECTION 1 Annual Meeting. The annual meeting of stockholders (any such meeting being referred to in these By-laws as an “Annual Meeting”) shall be held at the hour, date and place within or without the United States which is fixed by the Board of Directors, which time, date and p

March 4, 2019 8-K

Amendments to Articles of Incorporation or Bylaws; Change in Fiscal Year, Financial Statements and Exhibits

8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): March 4, 2019 KALEIDO BIOSCIENCES, INC. (Exact name of registrant as specified in its charter) Delaware 001-38822 47-3048279 (State or other jurisdiction of Incorporation) (Commis

March 4, 2019 EX-3.1

Amended and Restated Certificate of Incorporation of Kaleido Biosciences, Inc. (Incorporated by reference to Exhibit 3.1 to the Registrant’s Current Report on Form 8-K filed on March 4, 2019)

EX-3.1 Exhibit 3.1 FIFTH AMENDED AND RESTATED CERTIFICATE OF INCORPORATION OF KALEIDO BIOSCIENCES, INC. Kaleido Biosciences, Inc., a corporation organized and existing under the laws of the State of Delaware (the “Corporation”), hereby certifies as follows: 1. The name of the Corporation is Kaleido Biosciences, Inc. The date of the filing of its original Certificate of Incorporation with the Secre

March 1, 2019 424B4

5,000,000 Shares Kaleido Biosciences, Inc. Common Stock

424B4 Table of Contents Filed pursuant to Rule 424(b)(4) Registration No. 333-229204 5,000,000 Shares Kaleido Biosciences, Inc. Common Stock This is an initial public offering of common stock of Kaleido Biosciences, Inc. We are selling 5,000,000 shares of common stock. The initial public offering price is $15.00 per share. Prior to this offering, there has been no public market for our common stoc

February 27, 2019 8-A12B

Form 8-A

8-A12B UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-A FOR REGISTRATION OF CERTAIN CLASSES OF SECURITIES PURSUANT TO SECTION 12(b) OR (g) OF THE SECURITIES EXCHANGE ACT OF 1934 Kaleido Biosciences, Inc.

February 25, 2019 CORRESP

KLDO / Kaleido Biosciences, Inc. CORRESP - -

CORRESP VIA EDGAR February 25, 2019 U.S. Securities and Exchange Commission Division of Corporation Finance 100 F Street, N.E. Washington, D.C. 20549 Attn: Irene Paik Erin Jaskot Re: Kaleido Biosciences, Inc. Acceleration Request for Registration Statement on Form S-1 File No. 333-229204 Requested Date: February 27, 2019 Requested Time: 4:00 p.m. Eastern Standard Time Dear Ms. Paik and Ms. Jaskot:

February 25, 2019 CORRESP

KLDO / Kaleido Biosciences, Inc. CORRESP - -

CORRESP VIA EDGAR February 25, 2019 U.S. Securities and Exchange Commission Division of Corporation Finance 100 F Street, N.E. Washington, D.C. 20549 Attn: Irene Paik Erin Jaskot Re: Kaleido Biosciences, Inc. Acceleration Request for Registration Statement on Form S-1 File No. 333-229204 Requested Date: February 27, 2019 Requested Time: 4:00 p.m. Eastern Standard Time Dear Ms. Paik and Ms. Jaskot:

February 22, 2019 S-1/A

- S-1/A

Table of Contents As filed with the Securities and Exchange Commission on February 22, 2019.

February 22, 2019 CORRESP

KLDO / Kaleido Biosciences, Inc. CORRESP - -

CORRESP February 22, 2019 VIA EDGAR AND FEDERAL EXPRESS United States Securities and Exchange Commission Division of Corporation Finance Mail Stop 4561 100 F Street, N.

February 19, 2019 EX-3.4

Form of Amended and Restated Bylaws (Incorporated by reference to Exhibit 3.4 to the registrant’s Registration Statement on Form S-1, as amended (File No. 333-229204)).

Exhibit 3.4 AMENDED AND RESTATED BY-LAWS OF KALEIDO BIOSCIENCES, INC. (the ?Corporation?) ARTICLE I Stockholders SECTION 1 Annual Meeting. The annual meeting of stockholders (any such meeting being referred to in these By-laws as an ?Annual Meeting?) shall be held at the hour, date and place within or without the United States which is fixed by the Board of Directors, which time, date and place ma

February 19, 2019 EX-10.10

Employment Agreement between the Registrant and Joshua Brumm, to be in effect upon the effectiveness of this Registration Statement

Exhibit 10.10 EXECUTION VERSION KALEIDO BIOSCIENCES, INC. EMPLOYMENT AGREEMENT This Employment Agreement (?Agreement?) is made as of January 24, 2019, between Kaleido Biosciences, Inc., a Delaware corporation (the ?Company?), and Joshua Brumm (the ?Employee?) and is effective as of the closing of the Company?s first underwritten public offering of its equity securities pursuant to an effective reg

February 19, 2019 EX-10.11

Employment Agreement between the Registrant and Katharine Knobil, M.D., dated January 24, 2019 (incorporated by reference to Exhibit 10.11 to the Registrant’s Registration Statement on Form S-1/A (File No. 333-229204) filed on February 19, 2019).

Exhibit 10.11 EXECUTION VERSION KALEIDO BIOSCIENCES, INC. EMPLOYMENT AGREEMENT This Employment Agreement (?Agreement?) is made as of January 24, 2019, between Kaleido Biosciences, Inc., a Delaware corporation (the ?Company?), and Katharine Knobil (the ?Employee?) and is effective as of the closing of the Company?s first underwritten public offering of its equity securities pursuant to an effective

February 19, 2019 EX-10.5

2019 Employee Stock Purchase Plan (incorporated by reference to Exhibit 10.5 to the Registrant’s Registration Statement on Form S-1/A (File No. 333-229204) filed on February 19, 2019).

Exhibit 10.5 KALEIDO BIOSCIENCES, INC. 2019 EMPLOYEE STOCK PURCHASE PLAN The purpose of the Kaleido Biosciences, Inc. 2019 Employee Stock Purchase Plan (?the Plan?) is to provide eligible employees of Kaleido Biosciences, Inc. (the ?Company?) and each Designated Subsidiary (as defined in Section 11) with opportunities to purchase shares of the Company?s common stock, par value $0.001 per share (th

February 19, 2019 EX-10.8

Employment Agreement between the Registrant and Michael Bonney, dated January 24, 2019 (incorporated by reference to Exhibit 10.8 to the Registrant’s Registration Statement on Form S-1/A (File No. 333-229204) filed on February 19, 2019).

Exhibit 10.8 EXECUTION VERSION KALEIDO BIOSCIENCES, INC. EMPLOYMENT AGREEMENT This Employment Agreement (?Agreement?) is made as of January 24, 2019, between Kaleido Biosciences, Inc., a Delaware corporation (the ?Company?), and Michael Bonney (the ?Employee?) and is effective as of the closing of the Company?s first underwritten public offering of its equity securities pursuant to an effective re

February 19, 2019 EX-4.2

Specimen Stock Certificate evidencing shares of common stock (Incorporated by reference to Exhibit 4.1 to the Registrant’s Form S-1/A filed on February 19, 2019)

Exhibit 4.2 ZQ|CERT#|COY|CLS|RGSTRY|ACCT#|TRANSTYPE|RUN#|TRANS# COMMON STOCK COMMON STOCK PAR VALUE $0.001 Certificate Number ZQ00000000 Shares * * 000000 ****************** * * * 000000 ***************** **** 000000 **************** ***** 000000 *************** ****** 000000 ************** KALEIDO BIOSCIENCES, INC. INCORPORATED UNDER THE LAWS OF THE STATE OF DELAWARE THIS CERTIFIES THAT is the ow

February 19, 2019 EX-10.9

Employment Agreement between the Registrant and Alison Lawton, to be in effect upon the effectiveness of this Registration Statement

Exhibit 10.9 EXECUTION VERSION KALEIDO BIOSCIENCES, INC. EMPLOYMENT AGREEMENT This Employment Agreement (?Agreement?) is made as of January 24, 2019, between Kaleido Biosciences, Inc., a Delaware corporation (the ?Company?), and Alison Lawton (the ?Employee?) and is effective as of the closing of the Company?s first underwritten public offering of its equity securities pursuant to an effective reg

February 19, 2019 EX-10.3

2019 Stock Option and Incentive Plan and forms of award agreements thereunder (incorporated by reference to Exhibit 10.3 to the Registrant’s Registration Statement on Form S-1/A (File No. 333-229204) filed on February 19, 2019).

Exhibit 10.3 KALEIDO BIOSCIENCES, INC. 2019 STOCK OPTION AND INCENTIVE PLAN SECTION 1. GENERAL PURPOSE OF THE PLAN; DEFINITIONS The name of the plan is the Kaleido Biosciences, Inc. 2019 Stock Option and Incentive Plan (the ?Plan?). The purpose of the Plan is to encourage and enable the officers, employees, Non-Employee Directors and Consultants of Kaleido Biosciences, Inc. (the ?Company?) and its

February 19, 2019 S-1/A

- S-1/A

Table of Contents As filed with the Securities and Exchange Commission on February 19, 2019.

February 19, 2019 EX-3.2

Form of Amended and Restated Certificate of Incorporation of the Registrant (Incorporated by reference to Exhibit 3.2 to the Registrant’s Registration Statement on Form S-1, as amended (File No. 333-229204)).

Exhibit 3.2 THIRD AMENDED AND RESTATED CERTIFICATE OF INCORPORATION OF KALEIDO BIOSCIENCES, INC. Kaleido Biosciences, Inc., a corporation organized and existing under the laws of the State of Delaware (the ?Corporation?), hereby certifies as follows: 1. The name of the Corporation is Kaleido Biosciences, Inc. The date of the filing of its original Certificate of Incorporation with the Secretary of

February 19, 2019 EX-10.1

Umbrella Development Services Agreement, by and between Patheon UK Limited and the Registrant, dated September 6, 2018 (incorporated by reference to Exhibit 10.1 to the Registrant’s Registration Statement on Form S-1/A (File No. 333-229204) filed on February 19, 2019).

Exhibit 10.1 CERTAIN CONFIDENTIAL PORTIONS OF THIS EXHIBIT WERE OMITTED AND REPLACED WITH ?[***]?. A COMPLETE VERSION OF THIS EXHIBIT HAS BEEN FILED SEPARATELY WITH THE SECRETARY OF THE SECURITIES AND EXCHANGE COMMISSION PURSUANT TO AN APPLICATION REQUESTING CONFIDENTIAL TREATMENT PURSUANT TO RULE 406 PROMULGATED UNDER THE SECURITIES ACT OF 1933, AS AMENDED. UMBRELLA DEVELOPMENT SERVICES AGREEMENT

January 18, 2019 CORRESP

KLDO / Kaleido Biosciences, Inc. CORRESP - -

CORRESP CONFIDENTIAL TREATMENT REQUESTED BY KALEIDO BIOSCIENCES, INC. CERTAIN PORTIONS OF THIS LETTER AS FILED VIA EDGAR HAVE BEEN OMITTED AND FILED SEPARATELY WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT TO THE OMITTED PORTIONS. OMITTED INFORMATION HAS BEEN REPLACED IN THIS LETTER AS FILED VIA EDGAR WITH A PLACEHOLDER IDENTIFIED BY THE MARK “[***].” January 18, 2019

January 11, 2019 EX-3.3

By-laws of the Registrant, as currently in effect

Exhibit 3.3 BY-LAWS OF VL32, INC. TABLE OF CONTENTS Page ARTICLE I STOCKHOLDERS 1 1.1 Place of Meetings 1 1.2 Annual Meeting 1 1.3 Special Meetings 1 1.4 Notice of Meetings 1 1.5 Voting List 1 1.6 Quorum 2 1. 7 Adjournments 2 1.8 Voting and Proxies 2 1.9 Action at Meeting 3 1.10 Conduct of Meetings 3 1.11 Action without Meeting 4 ARTICLE II DIRECTORS 5 2.1 General Powers 5 2.2 Number, Election and

January 11, 2019 EX-3.1

Amended and Restated Certificate of Incorporation of the Registrant, as currently in effect

Exhibit 3.1 AMENDED AND RESTATED CERTIFICATE OF INCORPORATION OF KALEIDO BIOSCIENCES, INC. (Pursuant to Sections 242 and 245 of the General Corporation Law of the State of Delaware) Kaleido Biosciences, Inc., a corporation organized and existing under and by virtue of the provisions of the General Corporation Law of the State of Delaware (the ?General Corporation Law?), DOES HEREBY CERTIFY: 1. Tha

January 11, 2019 EX-10.6

Form of Indemnification Agreement between the Registrant and each of its directors

Exhibit 10.6 KALEIDO BIOSCIENCES, INC. [FORM OF] DIRECTOR INDEMNIFICATION AGREEMENT This Indemnification Agreement (?Agreement?) is made as of [ ] by and between Kaleido Biosciences, Inc., a Delaware corporation (the ?Company?), and [Director] (?Indemnitee?). RECITALS WHEREAS, the Company desires to attract and retain the services of highly qualified individuals, such as Indemnitee, to serve the C

January 11, 2019 EX-4.3

Second Warrant to Purchase Stock, dated October 13, 2017, issued by the Registrant to Pacific Western Bank

Exhibit 4.3 THIS WARRANT AND THE SHARES ISSUABLE HEREUNDER HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, AND MAY NOT BE SOLD, PLEDGED OR OTHERWISE TRANSFERRED EXCEPT IN ACCORDANCE WITH APPLICABLE LAW. THIS WARRANT AND THE SHARES ISSUABLE HEREUNDER ARE SUBJECT TO THE RESTRICTIONS ON TRANSFER SET FORTH IN SECTION 4 OF THIS WARRANT. SECOND WARRANT TO PURCHASE STOCK Corporatio

January 11, 2019 EX-10.4

Senior Executive Cash Incentive Bonus Plan

Exhibit 10.4 KALEIDO BIOSCIENCES, INC. SENIOR EXECUTIVE CASH INCENTIVE BONUS PLAN 1. Purpose This Senior Executive Cash Incentive Bonus Plan (the ?Incentive Plan?) is intended to provide an incentive for superior work and to motivate eligible executives of Kaleido Biosciences, Inc. (the ?Company?) and its subsidiaries toward even higher achievement and business results, to tie their goals and inte

January 11, 2019 EX-10.13

Lease Agreement by and between HCP/King Hayden Campus LLC and the Registrant, dated March 19, 2018

Exhibit 10.13 65 HAYDEN AVENUE LEXINGTON, MASSACHUSETTS 02421 LEASE SUMMARY SHEET Execution Date: March 19, 2018 Tenant: KALEIDO BIOSCIENCES, INC., a Delaware corporation Tenant?s Mailing Address Prior to Occupancy: Kaleido Biosciences, Inc. 18 Crosby Drive Bedford, MA 01730 Attention: Chief Financial Officer Landlord: HCP/KING HAYDEN CAMPUS LLC, a Delaware limited liability company Building: 65 H

January 11, 2019 S-1

Registration Statement - S-1

Table of Contents As filed with the Securities and Exchange Commission on January 11, 2019.

January 11, 2019 EX-4.4

Amended and Restated Warrant to Purchase Stock, dated October 13, 2017, issued by the Registrant to Pacific Western Bank

Exhibit 4.4 THIS WARRANT AND THE SHARES ISSUABLE HEREUNDER HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, AND MAY NOT BE SOLD, PLEDGED OR OTHERWISE TRANSFERRED EXCEPT IN ACCORDANCE WITH APPLICABLE LAW. THIS WARRANT AND THE SHARES ISSUABLE HEREUNDER ARE SUBJECT TO THE RESTRICTIONS ON TRANSFER SET FORTH IN SECTION 4 OF THIS WARRANT. This warrant replaces the Warrant to Purcha

January 11, 2019 EX-4.1

Second Amended and Restated Investors’ Rights Agreement among the Registrant and certain of its stockholders, dated February 21, 2018 (Incorporated by reference to Exhibit 4.1 to the Registrant’s Form S-1 filed on January 11, 2019)

Exhibit 4.1 SECOND AMENDED AND RESTATED INVESTORS? RIGHTS AGREEMENT THIS SECOND AMENDED AND RESTATED INVESTORS? RIGHTS AGREEMENT (this ?Agreement?) is made as of February 21, 2018, by and among Kaleido Biosciences, Inc., a Delaware corporation (the ?Company?), and each of the investors listed on Schedule A hereto (each, an ?Investor,? and together with any subsequent investors, or transferees, who

January 11, 2019 EX-1.1

Form of Underwriting Agreement

Exhibit 1.1 KALEIDO BIOSCIENCES, INC. [ ? ] Shares of Common Stock Underwriting Agreement [ ? ], 2019 Goldman Sachs & Co LLC J.P. Morgan Securities LLC Morgan Stanley & Co. LLC As Representatives of the several Underwriters listed in Schedule 1 hereto c/o Goldman Sachs & Co. LLC 200 West Street New York, New York 10282 c/o J.P. Morgan Securities LLC 383 Madison Avenue New York, New York 10179 c/o

January 11, 2019 EX-10.2

2015 Stock Incentive Plan and forms of award agreements thereunder

Exhibit 10.2 KALEIDO BIOSCIENCES, INC. 2015 STOCK INCENTIVE PLAN 1. Purpose The purpose of this 2015 Stock Incentive Plan (the ?Plan?) of Kaleido Biosciences, Inc., a Delaware corporation (the ?Company?), is to advance the interests of the Company?s stockholders by enhancing the Company?s ability to attract, retain and motivate persons who are expected to make important contributions to the Compan

January 11, 2019 EX-10.12

Loan and Security Agreement between the Registrant and Pacific Western Bank, dated December 21, 2015, as amended to date

Exhibit 10.12 KALEIDO BIOSCIENCES, INC. LOAN AND SECURITY AGREEMENT This LOAN AND SECURITY AGREEMENT (the ?Agreement?) is entered into as of December 21, 2015, by and between PACIFIC WESTERN BANK, a California state chartered bank (?Bank?) and KALElDO BIOSCIENCES, INC. (?Borrower?). RECITALS Borrower wishes to obtain credit from time to time from Bank, and Bank desires to extend credit to Borrower

January 11, 2019 EX-10.14

Lease Agreement by and between DIV Bedford, LLC and the Registrant, dated May 15, 2017

Exhibit 10.14 XCHANGE AT BEDFORD LEASE between DIV BEDFORD, LLC, as Landlord and KALEIDO BIOSCIENCES, INC., as Tenant 18 Crosby Drive Bedford, Massachusetts As of May 15, 2017 TABLE OF CONTENTS ARTICLE 1 GRANT 1 ARTICLE 2 TERM 3 ARTICLE 3 COMPLETION AND OCCUPANCY OF THE PREMISES 3 ARTICLE 4 RENT AND SECURITY 4 ARTICLE 5 ADDITIONAL RENT FOR ESCALATIONS IN REAL ESTATE TAXES AND OPERATING EXPENSES 6

January 11, 2019 EX-10.7

Form of Indemnification Agreement between the Registrant and each of its executive officers

Exhibit 10.7 KALEIDO BIOSCIENCES, INC. [FORM OF] OFFICER INDEMNIFICATION AGREEMENT This Indemnification Agreement (?Agreement?) is made as of [ ] by and between Kaleido Biosciences, Inc., a Delaware corporation (the ?Company?), and [Officer] (?Indemnitee?).1 RECITALS WHEREAS, the Company desires to attract and retain the services of highly qualified individuals, such as Indemnitee, to serve the Co

January 11, 2019 EX-21.1

Subsidiaries of the Registrant

EX-21.1 15 d624275dex211.htm EX-21.1 Exhibit 21.1 SUBSIDIARIES Subsidiary Jurisdiction of Incorporation Cadena Bio, Inc. Delaware Kaleido Biosciences Securities Corporation Massachusetts

November 21, 2018 EX-1.1

KALEIDO BIOSCIENCES, INC. [ 🌑 ] Shares of Common Stock Underwriting Agreement

Exhibit 1.1 KALEIDO BIOSCIENCES, INC. [ ? ] Shares of Common Stock Underwriting Agreement [ ? ], 2018 Goldman Sachs & Co LLC J.P. Morgan Securities LLC Morgan Stanley & Co. LLC As Representatives of the several Underwriters listed in Schedule 1 hereto c/o Goldman Sachs & Co. LLC 200 West Street New York, New York 10282 c/o J.P. Morgan Securities LLC 383 Madison Avenue New York, New York 10179 c/o

November 21, 2018 DRSLTR

KLDO / Kaleido Biosciences, Inc. DRSLTR - -

DRSLTR November 21, 2018 VIA EDGAR AND FEDERAL EXPRESS United States Securities and Exchange Commission Division of Corporation Finance Mail Stop 4561 100 F Street, N.

November 21, 2018 EX-3.3

BY-LAWS VL32, INC.

Exhibit 3.3 BY-LAWS OF VL32, INC. TABLE OF CONTENTS Page ARTICLE I STOCKHOLDERS 1 1.1 Place of Meetings 1 1.2 Annual Meeting 1 1.3 Special Meetings 1 1.4 Notice of Meetings 1 1.5 Voting List 1 1.6 Quorum 2 1. 7 Adjournments 2 1.8 Voting and Proxies 2 1.9 Action at Meeting 3 1.10 Conduct of Meetings 3 1.11 Action without Meeting 4 ARTICLE II DIRECTORS 5 2.1 General Powers 5 2.2 Number, Election and

November 21, 2018 EX-10.4

KALEIDO BIOSCIENCES, INC. SENIOR EXECUTIVE CASH INCENTIVE BONUS PLAN

Exhibit 10.4 KALEIDO BIOSCIENCES, INC. SENIOR EXECUTIVE CASH INCENTIVE BONUS PLAN 1. Purpose This Senior Executive Cash Incentive Bonus Plan (the ?Incentive Plan?) is intended to provide an incentive for superior work and to motivate eligible executives of Kaleido Biosciences, Inc. (the ?Company?) and its subsidiaries toward even higher achievement and business results, to tie their goals and inte

November 21, 2018 EX-10.2

KALEIDO BIOSCIENCES, INC. 2015 STOCK INCENTIVE PLAN

Exhibit 10.2 KALEIDO BIOSCIENCES, INC. 2015 STOCK INCENTIVE PLAN 1. Purpose The purpose of this 2015 Stock Incentive Plan (the ?Plan?) of Kaleido Biosciences, Inc., a Delaware corporation (the ?Company?), is to advance the interests of the Company?s stockholders by enhancing the Company?s ability to attract, retain and motivate persons who are expected to make important contributions to the Compan

November 21, 2018 EX-10.14

65 HAYDEN AVENUE LEXINGTON, MASSACHUSETTS 02421 LEASE SUMMARY SHEET PAGE 1

Exhibit 10.14 65 HAYDEN AVENUE LEXINGTON, MASSACHUSETTS 02421 LEASE SUMMARY SHEET Execution Date: March 19, 2018 Tenant: KALEIDO BIOSCIENCES, INC., a Delaware corporation Tenant?s Mailing Address Prior to Occupancy: Kaleido Biosciences, Inc. 18 Crosby Drive Bedford, MA 01730 Attention: Chief Financial Officer Landlord: HCP/KING HAYDEN CAMPUS LLC, a Delaware limited liability company Building: 65 H

November 21, 2018 EX-4.1

SECOND AMENDED AND RESTATED INVESTORS’ RIGHTS AGREEMENT

Exhibit 4.1 SECOND AMENDED AND RESTATED INVESTORS? RIGHTS AGREEMENT THIS SECOND AMENDED AND RESTATED INVESTORS? RIGHTS AGREEMENT (this ?Agreement?) is made as of February 21, 2018, by and among Kaleido Biosciences, Inc., a Delaware corporation (the ?Company?), and each of the investors listed on Schedule A hereto (each, an ?Investor,? and together with any subsequent investors, or transferees, who

November 21, 2018 EX-10.15

XCHANGE AT BEDFORD DIV BEDFORD, LLC, as Landlord KALEIDO BIOSCIENCES, INC., as Tenant 18 Crosby Drive Bedford, Massachusetts As of May 15, 2017

Exhibit 10.15 XCHANGE AT BEDFORD LEASE between DIV BEDFORD, LLC, as Landlord and KALEIDO BIOSCIENCES, INC., as Tenant 18 Crosby Drive Bedford, Massachusetts As of May 15, 2017 TABLE OF CONTENTS ARTICLE 1 GRANT 1 ARTICLE 2 TERM 3 ARTICLE 3 COMPLETION AND OCCUPANCY OF THE PREMISES 3 ARTICLE 4 RENT AND SECURITY 4 ARTICLE 5 ADDITIONAL RENT FOR ESCALATIONS IN REAL ESTATE TAXES AND OPERATING EXPENSES 6

November 21, 2018 EX-10.6

KALEIDO BIOSCIENCES, INC. [FORM OF] DIRECTOR INDEMNIFICATION AGREEMENT

Exhibit 10.6 KALEIDO BIOSCIENCES, INC. [FORM OF] DIRECTOR INDEMNIFICATION AGREEMENT This Indemnification Agreement (?Agreement?) is made as of [ ] by and between Kaleido Biosciences, Inc., a Delaware corporation (the ?Company?), and [Director] (?Indemnitee?). RECITALS WHEREAS, the Company desires to attract and retain the services of highly qualified individuals, such as Indemnitee, to serve the C

November 21, 2018 EX-3.1

AMENDED AND RESTATED CERTIFICATE OF INCORPORATION KALEIDO BIOSCIENCES, INC. (Pursuant to Sections 242 and 245 of the General Corporation Law of the State of Delaware)

Exhibit 3.1 AMENDED AND RESTATED CERTIFICATE OF INCORPORATION OF KALEIDO BIOSCIENCES, INC. (Pursuant to Sections 242 and 245 of the General Corporation Law of the State of Delaware) Kaleido Biosciences, Inc., a corporation organized and existing under and by virtue of the provisions of the General Corporation Law of the State of Delaware (the ?General Corporation Law?), DOES HEREBY CERTIFY: 1. Tha

November 21, 2018 EX-10.7

KALEIDO BIOSCIENCES, INC. [FORM OF] OFFICER INDEMNIFICATION AGREEMENT

Exhibit 10.7 KALEIDO BIOSCIENCES, INC. [FORM OF] OFFICER INDEMNIFICATION AGREEMENT This Indemnification Agreement (?Agreement?) is made as of [ ] by and between Kaleido Biosciences, Inc., a Delaware corporation (the ?Company?), and [Officer] (?Indemnitee?).1 RECITALS WHEREAS, the Company desires to attract and retain the services of highly qualified individuals, such as Indemnitee, to serve the Co

November 21, 2018 EX-4.3

SECOND WARRANT TO PURCHASE STOCK Corporation: KALEIDO BIOSCIENCES, INC. Number of Shares: 51,413 Class of Stock: Series B Preferred Initial Exercise Price: $3.89 per share Issue Date: October 13, 2017 Expiration Date: October 13, 2027

Exhibit 4.3 THIS WARRANT AND THE SHARES ISSUABLE HEREUNDER HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, AND MAY NOT BE SOLD, PLEDGED OR OTHERWISE TRANSFERRED EXCEPT IN ACCORDANCE WITH APPLICABLE LAW. THIS WARRANT AND THE SHARES ISSUABLE HEREUNDER ARE SUBJECT TO THE RESTRICTIONS ON TRANSFER SET FORTH IN SECTION 4 OF THIS WARRANT. SECOND WARRANT TO PURCHASE STOCK Corporatio

November 21, 2018 EX-10.1

SECRETARY OF THE SECURITIES AND EXCHANGE COMMISSION PURSUANT TO AN APPLICATION REQUESTING CONFIDENTIAL TREATMENT PURSUANT TO RULE 406 PROMULGATED UNDER THE SECURITIES ACT OF 1933, AS AMENDED. UMBRELLA DEVELOPMENT SERVICES AGREEMENT 1. Parties: Patheo

Exhibit 10.1 CERTAIN CONFIDENTIAL PORTIONS OF THIS EXHIBIT WERE OMITTED AND REPLACED WITH ?[***]?. A COMPLETE VERSION OF THIS EXHIBIT HAS BEEN FILED SEPARATELY WITH THE SECRETARY OF THE SECURITIES AND EXCHANGE COMMISSION PURSUANT TO AN APPLICATION REQUESTING CONFIDENTIAL TREATMENT PURSUANT TO RULE 406 PROMULGATED UNDER THE SECURITIES ACT OF 1933, AS AMENDED. UMBRELLA DEVELOPMENT SERVICES AGREEMENT

November 21, 2018 EX-4.4

AMENDED AND RESTATED WARRANT TO PURCHASE STOCK Corporation: KALEIDO BIOSCIENCES, INC. Number of Shares: 85,617 Class of Stock: Series A Preferred Initial Exercise Price: $0.73 per share Issue Date: October 13, 2017 Expiration Date: December 21, 2025

Exhibit 4.4 THIS WARRANT AND THE SHARES ISSUABLE HEREUNDER HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, AND MAY NOT BE SOLD, PLEDGED OR OTHERWISE TRANSFERRED EXCEPT IN ACCORDANCE WITH APPLICABLE LAW. THIS WARRANT AND THE SHARES ISSUABLE HEREUNDER ARE SUBJECT TO THE RESTRICTIONS ON TRANSFER SET FORTH IN SECTION 4 OF THIS WARRANT. This warrant replaces the Warrant to Purcha

November 21, 2018 EX-21.1

SUBSIDIARIES Subsidiary Jurisdiction of Incorporation Cadena Bio, Inc. Delaware Kaleido Biosciences Securities Corporation Massachusetts

Exhibit 21.1 SUBSIDIARIES Subsidiary Jurisdiction of Incorporation Cadena Bio, Inc. Delaware Kaleido Biosciences Securities Corporation Massachusetts

November 21, 2018 DRS/A

-

Table of Contents As confidentially submitted to the Securities and Exchange Commission on November 21, 2018 as Amendment No.

October 26, 2018 DRS/A

-

Table of Contents As confidentially submitted to the Securities and Exchange Commission on October 26, 2018 as Amendment No.

October 26, 2018 EX-10.1

SECRETARY OF THE SECURITIES AND EXCHANGE COMMISSION PURSUANT TO AN APPLICATION REQUESTING CONFIDENTIAL TREATMENT PURSUANT TO RULE 406 PROMULGATED UNDER THE SECURITIES ACT OF 1933, AS AMENDED. UMBRELLA DEVELOPMENT SERVICES AGREEMENT 1. Parties: Patheo

Exhibit 10.1 CERTAIN CONFIDENTIAL PORTIONS OF THIS EXHIBIT WERE OMITTED AND REPLACED WITH ?[***]?. A COMPLETE VERSION OF THIS EXHIBIT HAS BEEN FILED SEPARATELY WITH THE SECRETARY OF THE SECURITIES AND EXCHANGE COMMISSION PURSUANT TO AN APPLICATION REQUESTING CONFIDENTIAL TREATMENT PURSUANT TO RULE 406 PROMULGATED UNDER THE SECURITIES ACT OF 1933, AS AMENDED. UMBRELLA DEVELOPMENT SERVICES AGREEMENT

October 26, 2018 DRSLTR

KLDO / Kaleido Biosciences, Inc. DRSLTR - -

DRSLTR October 26, 2018 VIA EDGAR AND FEDERAL EXPRESS United States Securities and Exchange Commission Division of Corporation Finance Mail Stop 4561 100 F Street, N.

September 25, 2018 DRS

-

Table of Contents As confidentially submitted to the Securities and Exchange Commission on September 25, 2018.

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