FOSTER CITY, Calif. — Gilead Sciences moved Monday to consolidate full ownership of one of oncology's most promising late-stage cell therapies, announcing a definitive agreement to acquire Arcellx for an implied equity value of $7.8 billion. The deal, which values Arcellx at $115 per share in cash at closing plus one non-transferable contingent value right worth an additional $5 per share, represents an 87% premium to the biotech's Friday closing price. Arcellx shares surged approximately 78% in premarket trading to $113.99, near the deal price.
The centerpiece of the acquisition is anitocabtagene autoleucel, known as anito-cel, a BCMA-directed CAR-T cell therapy Arcellx has been co-developing with Kite Pharma, Gilead's cell therapy division, since 2022. The FDA has accepted Arcellx's Biologics License Application for anito-cel as a fourth-line treatment for adult patients with relapsed or refractory multiple myeloma, with a Prescription Drug User Fee Act action date of December 23, 2026. Pivotal Phase 2 iMMagine1 study data showed a 96% response rate in patients whose disease had failed at least three prior lines of therapy.
For Gilead, the transaction represents a major strategic recommitment to cell therapy after a challenging stretch. The company disclosed in its most recent earnings report that overall cell therapy revenue fell 7% in 2025 and projected another 10% decline in 2026. Gilead CEO Daniel O'Day framed the deal as a conviction bet on anito-cel's long-term potential, including the possibility that the therapy could become a foundational treatment in earlier lines of multiple myeloma care and inform next-generation in vivo cell therapy programs.
The acquisition eliminates profit-sharing, milestones, and royalties between the two companies, simplifying the commercial structure ahead of a potential launch. Gilead already owned approximately 11.5% of Arcellx's outstanding shares prior to Monday's announcement. The transaction, approved by both boards, is structured as a tender offer followed by a second-step merger and is expected to close in the second quarter of 2026, subject to regulatory approval. Gilead expects the deal to be accretive to earnings per share beginning in 2028, contingent on FDA approval.
Gilead shares fell about 1% in premarket trading — a common reaction for a large-cap acquirer committing significant cash. Analysts at RBC Capital noted anito-cel showed "generally comparable efficacy" to Johnson & Johnson's Carvykti, already approved in the same indication, while flagging questions about market entrenchment. Competitor stocks in the CAR-T and cell therapy space, including Bristol-Myers Squibb, were modestly lower on competitive concern. The CVR component, payable if anito-cel achieves at least $6 billion in cumulative global net sales through year-end 2029, offers Arcellx shareholders additional upside tied directly to commercial execution.
The deal injects fresh M&A momentum into the biotech sector at a time when large-cap pharmaceutical companies are hunting for pipeline assets to offset patent expirations. Shares of other oncology-focused biotechs moved higher on speculation that the acquisition could signal broader consolidation interest in the cell therapy space.