LEI: 549300Q7EXQQH6KF7Z84

15 April 2026

RTW Biotech Opportunities Ltd

Obsidian Therapeutics reverse merger with Galera

·      Reverse merger concurrent with $350 million private placement financing

·      New company expected to begin trading in Q3 2026

·      As at 31 March 2026, Obsidian represented 0.3% of the Company's NAV

RTW Biotech Opportunities Ltd ("the Company"), the London Stock Exchange-listed investment company focused on identifying transformative assets with high growth potential across the life sciences sector, is pleased to the note the announcement by Galera Therapeutics, Inc. ("Galera" OTC: GRTX) that it has entered into a definitive merger agreement to combine with private portfolio company Obsidian Therapeutics, Inc. ("Obsidian"). The transaction is expected to close in the third quarter of 2026 and the new company will trade on the Nasdaq under the ticker symbol "OBX".

Obsidian is a clinical-stage biopharmaceutical company harnessing protein-regulation technology to develop cell therapies for the treatment of patients with solid tumours. Its lead product candidate, OBX-115, is currently in a Phase 2 trial for the treatment of advanced melanoma and a Phase 1 trial for the treatment of non-small cell lung cancer.

The merger is an all-stock transaction and occurs concurrently with a $350 million private placement financing, in which the Company is participating. As at 31 March 2026, Obsidian represented 0.3% of the Company's NAV.

Rod Wong, CIO of RTW Investments, said, "We are excited to support Obsidian as it enters the public markets through a reverse merger with Galera. Obsidian's cell therapy platform has the potential to meaningfully improve outcomes for oncology patients with solid tumours, and this transaction provides the capital and runway to advance OBX-115 through key clinical milestones. A reverse merger offers an efficient and attractive pathway for private companies to access the public markets, particularly as the IPO window continues to gradually reopen this year. Looking ahead, the next few months represent a significant period for oncology, with ASCO in May serving as a key inflection point. Several upcoming catalysts have the potential to reshape the standard of care across pancreatic, bladder and breast cancer."

The announcement can be found here.

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About RTW Biotech Opportunities Ltd:

RTW Biotech Opportunities Ltd (LSE: RTW) is an investment fund focused on identifying transformative assets with high growth potential across the biopharmaceutical and medical technology sectors. Driven by a long-term approach to support innovative businesses, RTW Biotech Opportunities Ltd invests in companies developing next-generation therapies and technologies that can significantly improve patients' lives. RTW Biotech Opportunities Ltd is managed by RTW Investments, LP, a leading healthcare-focused entrepreneurial investment firm with deep scientific expertise and a strong track record of supporting companies developing life-changing therapies.

Visit the website at www.rtwbio.com for more information.

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The information in this announcement may include forward-looking statements, which are based on the current expectations and projections about future events, and in certain cases can be identified by the use of terms such as "may", "will", "should", "expect", "anticipate", "project", "estimate", "intend", "continue", "target", "believe" (or the negatives thereon) or other variations thereon or comparable terminology. These forward-looking statements, as well as those included in any related materials, are subject to risks, uncertainties and assumptions about the Company and/or its underlying investments, including, among other things, the development of the applicable entity's business, trends in its operating industry, expected use of financing proceeds and future capital expenditures and acquisitions. In light of these risks, uncertainties and assumptions, the events in the forward-looking statements may not occur.