Roche and Hansoh Pharmaceutical Group have launched their second collaboration focused on developing cancer-fighting antibody-drug conjugates (ADCs), a partnership that could generate more than $15 billion for the Shanghai-based drug developer.

Roche and Hansoh have agreed to develop an unspecified number of ADCs “across multiple cancer types,” without disclosing the cancer types and targets they plan to focus on. The companies did say, however, that their strategic collaboration will consist of two preclinical Hansoh ADC programs and “multiple” ADC programs based on Roche-identified targets, to be developed through Hansoh’s ADC technology platform.

“Expanding our strategic collaboration with Hansoh marks an important step in advancing our ADC vision,” Boris L. Zaïtra, head of Corporate Business Development at Roche, said in a statement. “Exploring next generation ADCs is one of the most compelling frontiers in oncology today, offering the opportunity to address critical unmet needs and accelerate potential therapies for patients worldwide.”

Roche’s latest Hansoh partnership was announced October 19, a year and two days after the pharma giant was granted an exclusive global license (excluding China, Hong Kong, Macau and Taiwan) by Hansoh to develop its HS-20110, an ADC being developed to treat colorectal cancer and other solid tumors. HS-20110 consists of a humanized anti-CDH17 monoclonal antibody covalently conjugated to topoisomerase inhibitor (TOPOi) payload.

At the time, Roche agreed to pay Hansoh $80 million upfront and up to $1.45 billion in potential development, regulatory approval, and commercialization milestone payments, plus royalties, toward developing HS-20110. The drug is under study in advanced colorectal cancer in a global Phase I/II trial (NCT07283367) in China whose primary completion date is December 31, 2029; as well as in advanced solid tumors in a global Phase I trial (NCT06892379) in the U.S. and China whose primary completion date is December 31.

“Building on the ADC partnership we announced last year, we are delighted to further strengthen our collaboration with Roche,” stated Eliza Sun, executive director of Hansoh’s board. “This new agreement reflects our shared commitment to advancing ADC innovation and underscores our strategy of leveraging our deep expertise to accelerate the development of transformative therapies for cancer patients globally.”

Investors sent Hansoh shares on the Hong Kong Stock Exchange rising nearly 10% over two days, from HKD 31.38 ($3.94) at the start of Monday trading to HKD 34.38 ($4.31) at Tuesday’s close. Roche’s two classes of stock traded on the SIX Swiss Exchange each climbed roughly 3% during the period: RO bearer shares rose from CHF 384.60 ($463.21) to CHF 395.60 ($476.46), while ROP participation certificates went from CHF 379.20 ($456.67) to CHF 389.90 ($469.56).

Four ADCs disclosed in pipeline

HS-20110—identified with the placeholder name “CHU”—is one of four cancer-fighting ADCs disclosed online in Roche’s pipeline, last updated July 23. The other three are:

• RG6648, a c-Mesenchymal-epithelial transition factor (cMET)-targeting ADC whose active antitumor payload is the antibody YL0010014. When released, YL0010014 is designed to arrest the cell cycle of tumor cells, leading to tumor cell apoptosis. MediLink licensed the ADC, which it called YL211, in 2024 for up to nearly $1 billion, including $50 million in upfront and near-term milestone payments.
• RG6810, a DLL3-targeted ADC with a topoisomerase I (Topo1) isomerase payload, being developed to treat small cell lung cancer (SCLC). Roche licensed the ADC, which it called IBI3009, from San Francisco and Suzhou-based Innovent Biologics last year for $80 million upfront and up to $1 billion in development and commercial milestone payments, plus tiered royalties on net sales.
• Tam-Peli (tambotatug pelitecan or RG6919), a B7H3-targeting ADC for solid tumors licensed worldwide except China, Hong Kong, and Macau in January from Suzhou, China-based MediLink, which called the candidate YL201. The ADC was developed using MediLink’s Tumor Microenvironment-Activatable LINker-payload (TMALIN^®) platform.

Last month, MediLink released positive interim data from the Phase III TAISHAN-302 trial (NCT06612151) assessing Tam-Peli vs. standard-of-care topotecan in Chinese patients with relapsed SCLC who progressed after prior platinum-based chemotherapy with or without a PD-L1 inhibitor. TAISHAN-302 met its primary endpoint of overall survival (OS) with Tam-Peli demonstrating a statistically significant and clinically meaningful OS benefit, reducing the risk of death by 54% (median OS 13.3 vs. 9.4 months; stratified HR=0.46; p<0.0001).

Tam-Peli also showed robust efficacy across secondary endpoints, significantly extending progression-free survival (PFS) (median PFS 7.4 vs. 2.8 months) and response rates (59.1% vs. 9.7%) vs. topotecan. The Tam-Peli data was presented at the International Association for the Study of Lung Cancer (IASLC) 2026 World Conference on Lung Cancer (WCLC) in Seoul with simultaneous publication in The New England Journal of Medicine.

Ongoing ADC collaborations

Roche has several other ongoing discovery and development collaborations with Chinese partners focused on ADCs.

In August, Roche’s Genentech subsidiary agreed to license ADCs it plans to develop with Shanghai-based DualityBio based on its DualityBio Unique Payload Antibody Conjugate (DUPAC) platform. The ADCs would be developed against Genentech-defined oncology targets using payloads from DUPAC. Roche agreed to pay DualityBio $45 million upfront and more than $1 billion in development, regulatory, and commercial milestone payments, plus tiered royalties.

Through its latest partnership with Hansoh, Roche aims to multiply the number of ADCs in its development pipeline and product portfolio. Roche now markets two ADCs. One is Kadcyla^® (ado-trastuzumab emtansine / RG3502), a HER2-targeted antibody and microtubule inhibitor conjugate approved to treat HER2-positive breast cancer. Kadcyla is under study in combination with Roche’s Tecentriq^® (atezolizumab) in the Phase III ASTEFANIA trial (NCT04873362) for high-risk early breast cancer.

The other marketed Roche ADC is Polivy^® (polatuzumab vedotin), which is approved for specific types of lymphoma.  While a consensus of analysts expects Kadcyla and Polivy to rack up a combined CHF 3.5 billion ($4.3 billion) this year, according to LSEG data cited by Reuters.

Hansoh has agreed to lead early development of the programs through the completion of global Phase Ia clinical trials. After that, Roche agreed to oversee further development of the programs worldwide except China, Hong Kong, Macau, and Taiwan—where Hansoh will retain all rights to develop, register and commercialize the programs.

Also outside China, Hong Kong, Macau, and Taiwan, Hansoh has the option to select up to two programs and contribute to their development. In return, Roche will pay Hansoh unspecified “incremental upside” payments stemming from their commercialization in the United States.

Roche has agreed to pay Hansoh $400 million upfront, an additional $110 million to be paid next year on the first anniversary of the collaboration, and more than $15 billion in payments tied to achieving development, regulatory, and commercialization milestones associated with the programs. Hansoh could also gain from Roche tiered royalties on potential future product sales.

Patent cliff pressure

The partnership is one of several collaborations through which Swiss-based Roche hopes to recoup sales it expects to lose as its aging blockbusters lose patent exclusivity. The best-selling of these drugs is its Genentech-marketed multiple sclerosis drug Ocrevus^® (ocrelizumab), which heads for the proverbial “patent cliff” in 2027. Ocrevus generated CHF 3.47 billion ($4.192 billion) in sales during January-June and CHF 7.01 billion ($8.467 billion) in 2025.

That sales pressure has prompted Roche to launch numerous collaborations: In addition to the Hansoh and DualityBio collaborations, Roche has partnered since August alone with:

• Rona Therapeutics, another Chinese biotech, on an agreement to license its RNA interference (RNAi) obesity and metabolic disease candidate targeting activin receptor-like kinase 7 (ALK7), announced October 13 and valued at up-to-$1.16 billion ($100 million upfront and near-term).
• Defand Therapeutics, a Chinese startup, on a drug discovery partnership of undisclosed value (though reportedly up to about $1 billion, up to $10 million of that upfront) to discover and develop molecular glue therapies for multiple cancer and immunology targets, announced October 7.
• Ataviastik Bio, a Cambridge, MA hematology drug developer, on a partnership to discover and develop small molecule therapeutics against multiple targets for cardiovascular, renal, and metabolic (CVRM) diseases, valued at up to $1.9 billion ($70 million upfront), announced September 24.
• Earendil Labs, a Wilmington, DE, biologics developer, on a research collaboration with Genentech to discover and develop multiple therapeutic bispecific antibody programs in oncology, valued at up to $1.15 billion ($55 million upfront), announced September 24.

At up-to-$15.5 billion, the latest Roche-Hansoh collaboration is among the largest but not the largest partnership between a Western pharma and a Chinese biotech. That distinction belongs to AstraZeneca’s up-to-$18.5 billion collaboration ($1.2 billion upfront) with CSPC Pharmaceutical Group to develop “multiple” injectable next-generation therapies for obesity and type 2 diabetes across eight programs announced in January. That does not include a separate up-to-$1.77 billion ($30 million upfront) partnership by the companies to develop small interfering RNA (siRNA) therapies for kidney diseases, launched in July.

In May, Bristol Myers Squibb (BMS) launched an up-to-$15.2 billion partnership with Hengrui Pharma to co-develop 13 early-stage programs in oncology, hematology, and immunology. The 13 consist of four oncology/hematology assets from Hengrui, four immunology assets from BMS, and five “innovative” assets to be jointly discovered and developed by both companies. Also in May, Pfizer inked an up to $10.5 billion oncology alliance with Innovent Biologics to develop 12 early-stage and de novo antibodies and antibody-drug conjugates (ADCs) designed to treat various cancers.