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)

Registrant’s telephone number, including area code: (617) 674-9000

Not Applicable

(Former name or former address, if changed since last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

Securities registered pursuant to Section 12(b) of the Act:

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company  ☒

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.  ☐

Item 5.02. Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.

Departure of Director and Appointment of New Director

On September 23, 2019, Jonathan McIntyre, Ph.D. tendered his resignation from the Board of Directors (the “Board”) and the Compensation Committee of the Board, effective as of September 30, 2019. Mr. McIntyre has decided to step down from the Board given the increased demands placed on him as the Chief Executive Officer of Motif FoodWorks. His departure is not the result of any disagreement with the Company on any matter relating to the Company’s operations, policies or practices.

Departure of Chief Operating Officer and Chief Financial Officer and Appointment of Principal Accounting Officer

On September 23, 2019, Joshua Brumm, the Chief Operating Officer and Chief Financial Officer of the Company, submitted notice to the Company of his resignation, effective as of October 11, to pursue an opportunity as President and Chief Executive Officer of a biotechnology company.

On September 26, 2019, the Company and Mr. Brumm executed a consulting and separation agreement (the “Consulting Agreement”). Pursuant to the Consulting Agreement, Mr. Brumm has agreed to provide advisory services to the Company upon request from October 11, 2019 (the “Resignation Date”) through December 31, 2019 (the “Consultation Period”). During the Consultation Period, all stock options granted to Mr. Brumm prior to the Resignation Date will continue to vest in accordance with their terms and Mr. Brumm shall have a period of 12 months following the termination of the Consultation Period to exercise any stock options that have vested as of the last day of the Consultation Period. The foregoing description of the separation agreement does not purport to be complete and is qualified in its entirety by the full text of the separation agreement, which will be filed as an exhibit to the Company’s Quarterly Report on Form 10-Q for the quarter ended September 30, 2019.

On September 25, 2019, the Board appointed, upon the effectiveness of Mr. Brumm’s resignation, Rick Scalzo, the Company’s Corporate Controller, as the Company’s principal accounting officer. Mr. Scalzo (age 33) joined the Company in 2018. Prior to joining the Company, Mr. Scalzo was Corporate Controller at several other biotechnology or pharmaceutical companies, including X4 Pharmaceuticals, Astellas Institute of Regenerative Medicine and Ocata Therapeutics, after beginning his career at PwC. Mr Scalzo is a CPA in the Commonwealth of Massachusetts and holds an MBA from the University of Massachusetts and a bachelor’s degree from Boston College.

Item 9.01 Exhibits

SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

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 October 11, 2019, to serve as President and Chief Executive Officer of a biotechnology company.

Kaleido will initiate a search for a Chief Financial Officer and Richard Scalzo, Corporate Controller, has been appointed to serve as Principal Accounting Officer and, in the interim, will assume certain of Mr. Brumm’s responsibilities. Mr. Brumm will continue as an advisor to Kaleido through December 31, 2019.

“On behalf of the Company and the Board, I want to thank Josh for his many contributions to Kaleido,” said Alison Lawton, President and Chief Executive Officer of Kaleido. “Josh was instrumental in leading Kaleido through two financings, including our IPO, which provided critical foundation to support our efforts to advance our platform and pipeline, including initiating five clinical studies. We are fortunate to have benefited from Josh’s leadership and expertise and we wish him the very best in his new role.”

“It has been a privilege to be a part of the Kaleido team as we have evolved into a public company and advanced several programs into clinical development, including initiating our first Phase 2 trial under an IND,” said Mr. Brumm. “With its unique approach to targeting the microbiome, Kaleido has the opportunity to lead the way in unlocking its promise to make an important impact on patients’ lives. I look forward to following the Company’s progress.”

About Kaleido Biosciences

Kaleido Biosciences is a clinical-stage healthcare company with a differentiated, chemistry-driven approach to leveraging the microbiome organ to treat disease and improve human health. The Company has built a human-centric proprietary product platform to enable the rapid and cost-efficient discovery and development of novel Microbiome Metabolic Therapies (MMT^™). MMTs are designed to modulate the metabolic output and profile of the microbiome by driving the function and distribution of the organ’s existing microbes. Kaleido is advancing a broad pipeline of MMT candidates with the potential to address a variety of diseases and conditions with significant unmet patient needs. To learn more, visit https://kaleido.com/.

Forward Looking Statements

This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended, including, without limitation, statements regarding the therapeutic potential of our MMT candidates and our strategy, business plans and focus. The words “may,” “will,” “could,” “would,” “should,” “expect,” “plan,” “anticipate,” “intend,” “believe,” “estimate,” “predict,” “project,” “potential,” “continue,” “target” and similar words and expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words or expressions. Any forward-looking statements in this press release are based on

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management’s current expectations and beliefs and are subject to a number of risks, uncertainties and important factors that may cause actual events or results to differ materially from those expressed or implied by any forward-looking statements contained in this press release, including, without limitation, those related to non-IND clinical studies of our MMT product candidates including statements regarding the rapidity at which our human-centric discovery and development platform can advance our MMT product candidates, the clinical development and safety profile of our MMT candidates and their therapeutic potential, whether and when, if at all, our MMT candidates will receive approval form the U.S. Food and Drug Administration and for which, if any, indications, competition from other biotechnology companies, and other risks identified in our SEC filings, including our most recent Quarterly Report on Form 10-Q, and subsequent filings with the SEC. Any forward-looking statements contained in this press release represent our views only as of the date hereof and should not be relied upon as representing its views as of any subsequent date. We explicitly disclaim any obligation to update any forward-looking statements.

Contact

Amy Reilly

617-890-5721

amy.reilly@kaleido.com

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