Surrogacy of Pathologic Complete Response in Trials of Neoadjuvant Therapy for Early Breast Cancer

Using surrogate end points to grant drug approvals is justified only when they can provide accurate prediction of a drug's effect on the long-term patient outcomes. Evidence currently available does not support pCR used alone as a reliable surrogate end point in regulatory neoadjuvant RCTs for BC. The surrogacy value at trial level of potentially more robust surrogate end points needs to be urgently tested.