Inhibrx Biosciences shares jumped about 37% after Reuters reported several pharmas — including Merck & Co. — are interested in buying two experimental oncology assets in a deal that could reach $9 billion. The reported package includes $8 billion for INBRX-106, an OX40 agonist with early Phase II/III head and neck cancer data suggesting a 45% objective response rate with Keytruda versus 30% for Keytruda alone, and $1 billion for ozekibart, a DR5 agonist recently filed in conventional chondrosarcoma.

Why It Matters To Oncology

• INBRX-106 is being studied with pembrolizumab in head and neck squamous cell carcinoma, where early data in more than 30 patients suggest a potential ORR lift from 30% to 45%.

• That signal matters because Merck is looking for ways to extend and deepen Keytruda’s franchise ahead of its 2028 patent cliff.

• Ozekibart adds a distinct mechanism: a tetravalent DR5 agonist designed to induce tumor-selective programmed cell death.

• In colorectal cancer, Inhibrx said this week that ozekibart plus chemotherapy produced a 20% ORR in 45 patients with locally advanced or metastatic, unresectable disease.

The Financials

• Reuters, citing people familiar with the matter, said the transaction could total $9 billion.

• The implied split: about $8 billion for INBRX-106 and $1 billion for ozekibart.

• Investors reacted quickly, sending Inhibrx shares up roughly 37% on Wednesday.

• The structure could resemble Inhibrx’s 2024 Sanofi deal, in which Sanofi paid about $1.7 billion for the company and its AATD asset, while the remaining pipeline continued in a new cash-backed entity.

What They're Saying

• Reuters reported that Merck & Co., Merck KGaA and Ono Pharmaceuticals are among the parties showing interest.

• The strategic logic is straightforward: INBRX-106’s valuation appears tied to its potential synergy with Keytruda, which generated $31.7 billion in 2024 sales.

• For ozekibart, the appeal is nearer-term optionality across conventional chondrosarcoma, refractory Ewing sarcoma and possible accelerated approval pathways in later-line colorectal cancer.

What's Next

• Inhibrx plans to report ORR results for INBRX-106 this quarter and present progression-free survival data at ESMO in October.

• FDA is now reviewing ozekibart in conventional chondrosarcoma following this month’s submission.

• Watch whether Inhibrx pursues a spinout-plus-sale structure similar to the Sanofi transaction rather than an outright asset sale.

• For clinicians and drug hunters alike, the next key question is whether these early efficacy signals hold up in larger datasets and support registrational paths.