Kaleido Biosciences to Appoint Dr. Alison Long as Chief Medical Officer

Kaleido Biosciences, Inc. (Nasdaq: KLDO), a clinical-stage biotech company with a differentiated, small-molecule approach to treating inflammatory conditions and diseases by selectively targeting the resident microbiome to restore gut-immune homeostasis, today announced the appointment of Alison Long, M.B.B.Ch., Ph.D., to its leadership team as Chief Medical Officer, effective December 15, 2021. In her new role, Dr. Long will be responsible for leading the development of Kaleido’s ongoing and future clinical programs, including the development of KB295 and KB109 in ulcerative colitis and chronic obstructive pulmonary disease, respectively.

“Alison is an exciting addition to our team who will play a critical role as we continue preparations to advance our two lead programs into Phase 2 clinical trials under IND and CTA next year,” said Dan Menichella, President and Chief Executive Officer of Kaleido. “Her extensive experience in drug development, which includes leading five clinical programs to regulatory approvals, will be invaluable as Kaleido moves towards advancing our Microbiome Metabolic Therapies into multiple indications. Additionally, she will lead our medical affairs team as well as support translational microbiome research and the development of further new drug development candidates.”

“I am honored to be joining this talented team at Kaleido during a pivotal stage of growth for the Company,” said Dr. Long. “There are significant opportunities to leverage the immunomodulatory potential of the human microbiome to treat disease. The data thus far has demonstrated Kaleido’s differentiated Microbiome Metabolic Therapy approach is the key to unlocking that potential. I look forward to working with the Kaleido team and applying important learnings from recent clinical readouts to continue this forward momentum and advancement of our clinical development activities.”

Dr. Long has almost two decades of experience working in the pharmaceutical and biotechnology industry, and a proven track record developing therapies, which include five successful regulatory approvals over her career. She most recently served as interim Chief Medical Officer and Senior Vice President, Head of Clinical Development at Freeline Therapeutics, and was responsible for the clinical development, clinical operations, medical affairs, and regulatory functions of Freeline’s development programs. Prior to her role at Freeline, she served as Head of Clinical Research and Development at Spark Therapeutics, where she oversaw the scientific and clinical development of all programs, including gene therapy in Huntington’s and Pompe diseases, as well as Inherited Retinal Disorders. Dr. Long has also previously served as Vice President, Clinical Development, Hemophilia at uniQure, Vice President, Head of Clinical at Aegerion Pharmaceuticals, and Medical Director with Biogen, where she focused on the development and subsequent EU approval of Elocta®. Prior to her executive positions, Dr. Long was a physician scientist at AFG Biosolutions and The Institute for Ethnomedicine, after spending 12 years as a practicing physician. She received her medical degree from the University of Witwatersrand, and Ph.D. in biodefense from George Mason University.

About Kaleido BiosciencesKaleido Biosciences is a clinical-stage biotech company with a differentiated, small-molecule approach to treating inflammatory conditions and diseases by selectively targeting the resident microbiome to restore gut-immune homeostasis. The Company has built a 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 gut’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 clinical study plans and timelines, plans and timing for regulatory filings, and the Company’s business focus. The words “may,” “will,” “could,” “would,” “should,” “expect,” “plan,” “anticipate,” “intend,” “believe,” “estimate,” “predict,” “project,” “potential,” “continue,” “target” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. Any forward-looking statements in this press release are based on 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 the breadth of our pipeline of product candidates, the strength of our proprietary product platform, the efficiency of our discovery and development approach, the clinical development and safety profile of our MMT candidates and their therapeutic potential, whether and when, if at all, regulatory agencies will approve our IND application or clinical trial applications for KB295 or KB109, whether and when, if at all, our MMT candidates will receive approval from the U.S. Food and Drug Administration or other regulatory agencies and for which, if any, indications, competition from other biotechnology companies, and other risks identified in our SEC filings, including our most recent Form 10-K, and subsequent filings with the SEC. We caution you not to place undue reliance on any forward-looking statements, which speak only as of the date they are made. We disclaim any obligation to publicly update or revise any such statements to reflect any change in expectations or in events, conditions or circumstances on which any such statements may be based, or that may affect the likelihood that actual results will differ from those set forth in the forward-looking statements.

Contacts:

Kaleido BiosciencesWilliam Duke, Jr.Chief Financial [e-mail]

Investors and MediaKotaro YoshidaArgot [e-mail]