Pfizer’s Tukysa Slows Breast Cancer When Added to First-Line Care

Pfizer Inc.’s Tukysa, when given as part of the initial treatment for an advanced form of breast cancer, delayed tumor growth by more than eight months, according to a study that may expand its use.

Patients getting Tukysa in addition to standard treatment for metastatic disease went for more than two years without the cancer progressing, compared to 16.3 months for those given traditional care. It increased the risk of side effects, particularly liver complications and diarrhea, with 14% of patients dropping out of the study and one death tied to the treatment.