GSK licenses Chimagen trispecific T-cell engager for up to $750 million, targeting phase-1 multiple myeloma study

GSK has entered a licensing agreement with China’s Chimagen Biosciences that could be worth as much as $750 million. The deal will allow GSK to begin phase‑1 testing of a trispecific T‑cell engager aimed at treating multiple myeloma next year.

The agreement follows a prior $300 million upfront payment GSK made two years ago for a trispecific candidate in lupus. While the specific targets of the new multiple myeloma candidate have not been disclosed, Chimagen says the molecule is designed to bind two tumor‑associated antigens and a T‑cell receptor, a strategy intended to improve efficacy and tolerability.

GSK noted that existing bispecific T‑cell engagers in multiple myeloma, such as Johnson & Johnson’s Tecvayli and Pfizer’s Elrexfio, have shown strong activity but carry boxed warnings for cytokine release syndrome and neurologic toxicity. The company hopes its trispecific design can deliver deeper, more durable responses with a better safety profile.

If successful, the product could be positioned earlier in the treatment pathway and potentially be used more broadly than current T‑cell engagers, expanding GSK’s oncology pipeline.