In 2017, the FDA granted accelerated approval to two PD-1/PD-L1 immunotherapies for the first-line treatment of cisplatin-ineligible bladder cancer patients, regardless of PD-L1 status, based on Phase II studies. However, data from ongoing Phase III trials subsequently demonstrated that patients with PD-L1 negative tumors who received first-line immunotherapy had decreased survival relative to non-cisplatin chemotherapy. As a result, in 2018, the FDA restricted the indication for these novel drugs to cisplatin-ineligible patients with PD-L1 positive tumors.
In collaboration with researchers from the FDA and the University of Pennsylvania, Flatiron tested the impact of an FDA alert and label change on clinical practice using real-world data obtained from electronic health records. Findings suggest that the FDA label changes were associated with changes in practice, even when the decision was based on emerging trial data.