The news: Roche is expanding its partnership with China’s Hansoh Pharmaceutical Group through a second antibody-drug conjugate (ADC) cancer deal potentially worth over $15 billion. For context, ADCs are targeted therapies that use antibodies to deliver cancer-killing drugs directly to specific tumor cells.

Hansoh will develop ADCs against targets selected by Roche through phase 1a trials, after which Roche will take over development. The companies are already partnering on an ADC for colorectal cancer.

Why it matters: Roche is building on its ADC cancer business through partnerships in China—a major hub of ADC development. Chinese companies accounted for about 70% of global ADC drug development over the past two and a half years, per a December Goldman Sachs report.

Roche has two ADCs approved in the US: Polivy, a blood cancer treatment that generated sales of about CHF 808 million ($1 billion) in H1 2026, and Kadcyla, breast cancer treatment that generated CHF 916 million ($1.1 billion) in the same period. But it has been expanding its pipeline with deals in China. In January, Roche signed a licensing deal with MediLink Therapeutics for an ADC targeting several solid tumor types. It also reached an agreement with DualityBio in August for next-generation ADCs designed for patients who progress even after treatment.

Implications for oncology pharma marketers: Commercial success for ADCs requires a new approach to physician education that simplifies the clinical complexity of the drugs .

Unlike more broadly used cancer treatments, ADCs often have narrower indications, with eligibility depending on cancer type, biomarker testing, and whether patients have tried other treatments. That can make identifying eligible patients and determining where ADCs fit into care more complex. For drugmakers and pharma marketers, healthcare provider outreach will need to go beyond raising awareness of new treatments to providing detailed guidance on patient selection, testing requirements, and when to consider ADCs in the course of treatment.