Major Pharma Companies Compete for $8+ Billion Inhibrx Cancer Drug That Could Enhance Keytruda
核心洞察
Inhibrx Biosciences has attracted interest from Merck & Co (搜索), Merck KGaA, and Ono Pharmaceutical for its experimental cancer drug INBRX-106, potentially valued at over $8 billion.
INBRX-106 is designed to boost Keytruda's efficacy, with preliminary Phase 2/3 trial data showing improved response rates from 30% to 45% when combined with the immunotherapy.
The biotech is exploring a joint spin-off of INBRX-106 and ozekibart, with combined potential value exceeding $9 billion if clinical trials succeed.
Inhibrx Biosciences has emerged as a major acquisition target, drawing interest from pharmaceutical giants including Merck & Co (搜索), Germany's Merck KGaA, and Japan's Ono Pharmaceutical for its experimental cancer treatment INBRX-106, which could be valued at more than $8 billion, according to sources familiar with the matter.
The San Diego-based biotech is exploring a joint spin-off of INBRX-106 and a second experimental cancer treatment, ozekibart, which could have a combined value of more than $9 billion if clinical trials succeed. Interest is particularly concentrated on INBRX-106, which is being tested both as a standalone therapy and in combination with Merck's blockbuster immunotherapy Keytruda.
Promising Combination Data with Keytruda
INBRX-106 has demonstrated significant potential to enhance the efficacy of Keytruda, the world's top-selling prescription medicine with more than $30 billion in annual sales. Keytruda accounted for almost half of Merck's global sales in 2025 and is approved to treat a wide variety of cancers.
Preliminary results from more than half of the 60 recruited patients in Phase 2/3 combination trials with Keytruda support the potential to improve patient overall response rates to 45%, compared to 30% with Keytruda alone, according to sources. The drug functions as an antibody that boosts immune response by activating a receptor on T cells, a key component of the immune system.
Clinical trials are being conducted in patients with advanced head and neck cancers, which have limited treatment options. The company is planning to disclose interim results next month, sources indicated.
"We think INBRX-106 is highly investable through targeting the narrow Keytruda-responder base to enhance this $32 billion drug's cure-like efficacy," Stifel biotech analyst Dara Azar said in a recent client note. Stifel initiated coverage of the largely unknown biotech this month with a "buy" rating and a $150 price target, while Inhibrx shares closed at $84.08 on Tuesday.
Second Asset Shows Promise in Rare Cancers
Inhibrx is also developing ozekibart, which received fast track and orphan drug designations from the U.S. Food and Drug Administration on Wednesday. The therapy has shown positive results in Phase 1/2 trials for Ewing sarcoma and colorectal cancer and could be valued at about $1 billion, according to sources.
Ozekibart is designed to promote cancer cell death. In one Ewing sarcoma study, patients saw tumors shrink by about 52%, the company has reported. Sources expect the company to disclose that it has filed for FDA approval of ozekibart.
Strategic Interest from Multiple Buyers
INBRX-106 would be of particular strategic interest to Merck, which is looking for new revenue sources as Keytruda faces the loss of patent protections in 2028. However, that strategic fit does not give Merck an advantage as a potential buyer, sources noted.
The drug could equally attract attention from other top-tier drugmakers looking to bolster their immuno-oncology offerings, including Eli Lilly, AstraZeneca, Pfizer, and Johnson & Johnson, according to sources.
Talks are in early stages and any deal would likely be several months away, with valuation hinging on upcoming trial results. The drug is unlikely to reach the market before Merck begins facing competition from less expensive biosimilar versions of Keytruda.
Inhibrx is considering a spinout structure similar to its 2024 deal with Sanofi, sources said. In that transaction, Sanofi acquired INBRX-101 for $30 per share in cash, plus a $5 contingent value right tied to regulatory milestones.
