Merck and Rivals Interested in Inhibrx Cancer Drug Deal Linked to Keytruda: Sources

• INBRX-106 could be valued at over $8 billion if trials confirm it can boost Keytruda's patient response rates from 30% to 45%, according to preliminary data from ongoing combination trials
• The deal is strategically important for Merck as Keytruda, which generated over $30 billion in annual sales (nearly half of Merck's 2025 revenue), faces patent expiration in 2028
• Inhibrx plans to disclose interim trial results next month and is also seeking FDA approval for ozekibart, a second cancer drug valued at approximately $1 billion that showed 52% tumor shrinkage in Ewing sarcoma patients

Market Summary: Merck and Rivals Eye Inhibrx Cancer Drug Deal

Key Development

San Diego-based Inhibrx Biosciences has attracted interest from major pharmaceutical companies including Merck & Co, Germany's Merck KGaA, and Japan's Ono Pharmaceutical for its experimental cancer treatment INBRX-106, valued at over $8 billion.

Deal Structure

Inhibrx is exploring a joint spin-off of INBRX-106 and a second experimental cancer drug (ozekibart), with combined potential value exceeding $9 billion contingent on successful clinical trial results. Talks are in early stages and a deal is likely several months away.

Critical Drug Details

INBRX-106 (valued at $8+ billion):

• Designed to boost efficacy of Merck's blockbuster Keytruda immunotherapy
• Preliminary trials show improvement in overall patient response rates to 45% versus 30% with Keytruda alone
• Interim results expected next month
• Being tested in advanced head and neck cancer patients

Ozekibart (valued at ~$1 billion):

• Received FDA fast track and orphan drug designations
• Showed 52% tumor shrinkage in Ewing sarcoma studies
• FDA approval filing expected imminently

Strategic Implications

INBRX-106 is particularly attractive to Merck as Keytruda—which generated over $30 billion in 2025 sales (nearly half of Merck's global revenue)—faces patent expiration in 2028. However, other major players including Eli Lilly, AstraZeneca, Pfizer, and J&J are also considered potential buyers seeking to strengthen immuno-oncology portfolios.

Stifel analyst Dara Azar initiated coverage with a "buy" rating and $150 price target, citing the drug's potential to enhance Keytruda's effectiveness for a broader patient base.