In a future TNBC landscape with new antibody-drug conjugates (ADCs), Pumitamig is framed as a fundamentally different tool. The expert views ADCs as a form of "chemotherapy," while Pumitamig is an "immunotherapeutic strategy." This conceptual separation suggests a future where these novel agents are used in combination or sequence, not in direct competition.
The bispecific antibody Pumitamig demonstrated identical overall response rates in both PD-L1 positive and negative triple-negative breast cancer patients. This is significant as it provides a potential immunotherapy option for the two-thirds of patients who are PD-L1 negative and currently ineligible for such treatments.
The Phase II study for Pumitamig intentionally combined the drug with various chemotherapy agents. The primary goal was not to directly compare efficacy between partners, but to establish a broad safety profile, ensuring a well-informed and flexible design for the subsequent, larger Phase III registrational trial.