Director Nominee and Retirement

Collegium Pharmaceutical, Inc. announced on April 6, 2026, that Michael Donovan has been nominated to stand for election at the Company’s 2026 Annual Meeting of Shareholders. Mr. Donovan, with extensive experience as an audit partner at Ernst & Young LLP, brings financial expertise in the life sciences industry, including audits, financings, M&A, and corporate agreements. Concurrently, on April 2, 2026, Dr. John Fallon informed the Board of his decision not to stand for re-election and will retire from the Board at the upcoming Annual Meeting after serving since 2016. This decision is part of the Board’s ongoing efforts in refreshment and succession planning and is not due to any disagreement with the Company. The Company expressed gratitude to Dr. Fallon for his service.