Oak Hill Bio and RACC Announce Major Business Combination to Form Rare Disease Biotech Powerhouse

Key Highlights of the Transaction

• Business Combination: Oak Hill Bio, a clinical-stage rare disease therapeutics company, and Research Alliance Corporation III (RACC), a SPAC sponsored by RA Capital Management, have entered into a definitive agreement to merge and form a publicly traded company focused on rare diseases.
• Financing: The transaction will provide Oak Hill Bio with approximately \$175 million in gross proceeds, consisting of \$75 million from RACC’s trust account (fully backstopped by RA Capital) and a \$100 million committed private financing.
• Oak Hill Bio’s recent \$32.5 million Series A financing adds to the company’s cash runway, expected to fund development of its lead asset through pivotal clinical milestones.
• Lead Program: Oak Hill Bio is advancing rugonersen (OHB-724), a potential best-in-class antisense oligonucleotide (ASO) therapy for Angelman syndrome, currently in a pivotal Phase 3 BEACON clinical trial.
• The first patient in the Phase 3 BEACON trial was dosed in July 2026.
• The combined company is expected to be listed on the Nasdaq Capital Market under the ticker symbol “OAKH“.
• The business combination is targeted to close by year-end 2026, pending customary shareholder and regulatory approvals.
• Current RACC Director and former Avidity Biosciences CFO, Mike MacLean, will remain on the Board post-closing, providing seasoned financial and operational leadership.

Strategic Rationale and Shareholder Considerations

• Transformational Funding: The combined proceeds from this transaction, together with Oak Hill Bio’s Series A financing, are expected to provide sufficient cash runway to support the development of rugonersen through Phase 3 readout and a potential new drug application (NDA) submission in the second half of 2029.
• High-Profile Investors: The \$100 million private financing is backed by a strong syndicate, including RA Capital (who funded \$45 million at signing via a SAFE), Balyasny Asset Management, Janus Henderson Investors, KCap Biotechnology Fund, venBio, ADAR1 Capital Management, Affinity Asset Advisors, Ally Bridge Group, BVF Partners, Great Point Partners, Logos Capital, SilverArc Capital, and Trails Edge Capital Partners.
• The PIPE portion of the financing is oversubscribed at \$10.00 per share, reflecting strong investor confidence and potentially supporting valuation stability post-merger.
• Price-Sensitive Milestones: The anticipated Phase 3 trial readout and NDA submission for rugonersen (targeted for 2H2029) represent significant, potentially share price-moving catalysts.
• Oak Hill Bio’s acquisition and further development of rugonersen, a program originated by Roche and now staffed by former Roche team members, enhances the credibility and potential of the asset.
• The transaction is unanimously approved by both boards, indicating alignment among key stakeholders.

About Oak Hill Bio and Rugonersen

• Oak Hill Bio focuses on acquiring and developing deprioritized but promising rare disease assets from pharmaceutical companies.
• Rugonersen is an investigational ASO designed to target and degrade the UBE3A-ATS transcript in the central nervous system, aiming to unsilence the paternal UBE3A allele and restore its expression in neurons. This mechanism addresses the root cause of Angelman syndrome, which affects approximately 30,000 diagnosed patients in the U.S. and EU5.
• Angelman syndrome is a serious neurodevelopmental disorder with no approved disease-modifying therapies. Symptoms include intellectual disability, epilepsy, ataxia, tremor, speech limitations, and sleep disturbances.
• Clinical data for rugonersen, including early-phase results published in Nature Medicine and Nucleic Acids Research, suggest potential for meaningful impact on patient outcomes.

About the Transaction Process

• The merger will see RACC redomicile as a Delaware corporation, renamed Oak Hill Bio, Inc., and trade under the ticker “OAKH”.
• The business combination is expected to close by year-end 2026, subject to customary closing conditions, including shareholder and regulatory approvals.
• Shareholders will be asked to vote on the transaction, with materials to be filed with the SEC and distributed prior to the meeting.
• Advisors on the transaction include Leerink Partners, UBS Investment Bank, Wells Fargo Securities, LifeSci Capital (joint placement agents), Goodwin Procter LLP (Oak Hill Bio’s legal counsel), Cooley LLP (RACC’s legal counsel), and Kirkland & Ellis LLP (placement agents’ legal counsel).

Forward-Looking Statements & Risk Factors

• Forward-looking statements cover expectations for clinical development, regulatory milestones, financial projections, and market opportunity.
• Risks: Key risks include clinical and regulatory uncertainties, competitive product developments, supply chain and talent acquisition challenges, ability to secure additional capital, macroeconomic and political factors, and the risk of not completing the business combination.
• Shareholders should review risk factors in RACC’s public filings, including the Form 10-Q for the quarter ended March 31, 2026, and other SEC documents, before making investment decisions.
• There is no guarantee the transaction will close as planned, or that the anticipated benefits and milestones will be realized.

Investor Implications

• This business combination and capital raise position Oak Hill Bio as a well-funded, focused developer of potentially transformative treatments for rare diseases, with a clear path to pivotal data and a potential NDA submission for its lead asset. These are major milestones that could drive significant value for shareholders, but also carry substantial risks given the stage of development and competitive landscape.
• All investors and shareholders are urged to read forthcoming SEC filings and proxy materials carefully before voting or investing.

View Research Alliance Corp III Historical chart here