On 23 October 2026, Junshi Biosciences announced that the first patient has been dosed in its registrational, randomized, open-label, multicenter Phase III clinical study (JS203-003-III-DLBCL; NCT07808827). The trial evaluates the company’s recombinant humanized anti-CD20/CD3 bispecific antibody JS203 plus chemotherapy against the current standard regimen of rituximab plus chemotherapy in patients with relapsed or refractory diffuse large B-cell lymphoma (DLBCL).
The study plans to enroll 282 participants and will measure overall survival as the primary endpoint. Professor Song Yuqin of Beijing Cancer Hospital serves as principal investigator.
JS203 Mechanism and Early-Stage Data • JS203 simultaneously targets CD20 on B-cells and CD3 on T-cells, redirecting T-cell cytotoxicity toward malignant B-cells. • Pre-clinical models demonstrated significant anti-tumor activity and favorable tolerability profiles. • Phase I findings presented at AACR 2025 (Abstract #CT025) showed an objective response rate (ORR) of 80% and a complete response rate (CRR) of 40% at the 30 mg dose among DLBCL patients; median duration of response was not reached. • Updated Phase I data disclosed at ASH 2025 (Abstract #1957) reported an ORR of 72.40% in all CD20-positive relapsed/refractory B-NHL patients at the recommended Phase II dose, including a 69.70% ORR and 39.40% CRR in the DLBCL subgroup. Cytokine release syndrome occurred in 27.30% of patients, with no cases of immune effector cell-associated neurotoxicity syndrome.
Market Context DLBCL accounts for roughly 40% of adult non-Hodgkin lymphoma in China, with approximately 45,000 new cases reported annually (GLOBOCAN 2022). Despite available therapies, relapsed or refractory patients face a median overall survival slightly over one year and a five-year survival rate near 30%, underscoring the need for more effective treatments.
Risk Disclosure Junshi Biosciences highlighted the inherent uncertainties of drug development, noting that long timelines and high technical risks may affect eventual outcomes. The company pledged to provide timely updates on material progress in accordance with regulatory requirements.