Keytruda's Broad Confirmatory Trials Suggest Evolution Of US FDA’s Accelerated Approval Model

The US FDA granted accelerated approval to Merck & Co. Inc.'s PD-1 inhibitor Keytruda on June 13 for a new indication in refractory primary mediastinal large B-cell lymphoma (PMBCL). But the confirmatory trial spelled out in the approval letter is more familiar: the ongoing Phase III KEYNOTE-204 trial, which is also serving as the confirmatory trial for an earlier Keytruda accelerated approval in refractory classic non-Hodgkin lymphoma.

The multiple-use confirmatory trial is becoming a more common sight in the fast-growing immuno-oncology space, and another example of the regulatory flexibility that FDA has established under its suite of...