BridgeBio Oncology and Helix Acquisition Announce Merger to Advance RAS & PI3Kα Therapies
BridgeBio Oncology Therapeutics (BBOT), a clinical-stage biopharmaceutical company focused on developing next-generation small molecule therapies targeting RAS and PI3Kα malignancies, has announced a definitive business combination agreement with Helix Acquisition Corp. II (Nasdaq: HLXB), a special purpose acquisition company (SPAC) sponsored by affiliates of Cormorant Asset Management. Upon completion of the transaction, the merged entity will be renamed “BridgeBio Oncology Therapeutics, Inc.,” with its common stock expected to trade on Nasdaq under the ticker symbol BBOT.
The transaction includes approximately $196 million held in Helix’s trust account, assuming no redemptions by public shareholders, as well as a $260 million PIPE financing from premier institutional investors. Leading participants in the PIPE include Cormorant Asset Management, ADAR1 Capital Management, BC Capital, Deerfield Management, Enavate Sciences, Eventide Asset Management, Novo Holdings A/S, Octagon Capital, Omega Funds, Paradigm BioCapital Advisors, StemPoint Capital LP, Surveyor Capital (a Citadel company), Wellington Management, and another leading mutual fund.
Eli Wallace, PhD, Chief Executive Officer of BBOT, highlighted the significance of this transaction: “This financing and transaction mark a significant milestone for our company. We are profoundly grateful to the patients who participate in our trials, our dedicated BBOT team members, and our investors. We believe this transaction is the optimal path to advance our programs and make a meaningful impact on patients affected by deadly cancers.”
The net proceeds from the transaction are expected to accelerate the development of BBOT’s three lead programs:
- BBO-8520 – A direct KRASG12C inhibitor targeting both “ON” and “OFF” states, currently in the Phase 1 ONKORAS-101 trial (NCT06343402) for patients with KRASG12C-mutant non-small cell lung cancer.
- BBO-10203 – An orally bioavailable small molecule designed to disrupt the interaction between RAS and PI3Kα, inhibiting RAS-driven PI3Kα-AKT signaling in tumors. It is under evaluation in the Phase 1 BREAKER-101 trial (NCT06625775) for patients with HER2+ breast cancer, HR+/HER2- breast cancer, KRAS mutant colorectal cancer, and KRAS mutant non-small cell lung cancer.
- BBO-11818 – A pan-KRAS inhibitor that targets multiple KRAS mutations, including KRASG12D and KRASG12V, with strong potency against both “ON” and “OFF” states. The first patient is expected to be dosed in the first half of 2025.
Bihua Chen, Founder and Chief Executive Officer of Cormorant and Chief Executive Officer of Helix, emphasized BBOT’s leadership and innovation in oncology: “BBOT’s team has some of the brightest minds in oncology, with a proven track record of developing new medicines. The company’s pipeline has the potential for paradigm-shifting impact on the treatment of some of the highest-prevalence malignancies, and we look forward to seeing patient impact further materialize as the clinical trials move forward.”
Transaction Overview
Upon closing, BBOT expects to have access to approximately $550 million in cash, prior to the payment of transaction costs and assuming no redemptions by Helix’s public shareholders. The funds will come from:
- $196 million held in Helix’s trust account (assuming no redemptions)
- $260 million in concurrent PIPE financing of common stock issued at the SPAC redemption price per share
- $100 million in existing BBOT cash at closing
Assuming a share price of $10.36 per share and no redemptions, the combined company will have an implied pro forma equity value of approximately $949 million at closing. BBOT shareholders will roll 100% of their equity into the combined entity and will not receive cash proceeds from the transaction.
The boards of directors of both BBOT and Helix have approved the proposed merger, which is expected to close in the third quarter of 2025, subject to shareholder approvals and other closing conditions.
Advisors
- Placement Agents for Helix: Leerink Partners, Morgan Stanley, Cantor, Oppenheimer & Co.
- Lead Capital Markets Advisor to Helix: Leerink Partners
- Capital Markets Advisor to BBOT: Piper Sandler
- Legal Counsel to BBOT: Goodwin Procter
- Legal Counsel to Helix: White & Case LLP
- Legal Counsel to Placement Agents: Kirkland & Ellis LLP
Further details about the transaction will be available in a Form 8-K filing by Helix with the SEC, accessible at www.sec.gov.
This business combination represents a significant step forward for BBOT, enabling it to advance its pipeline of next-generation RAS and PI3Kα-targeting therapies, which have the potential to reshape cancer treatment paradigms and improve patient outcomes worldwide.
