Patients with mUC and Low PD-L1 Expression May Have Decreased Survival When Treated with Pembrolizumab or Atezolizumab

The FDA safety alert considers treatment of patients with metastatic urothelial cancer who have not received prior therapy

On 18 May 2018, the US Food and Drug Administration (FDA) alerted healthcare professionals, oncology clinical investigators, and the public about decreased survival associated with the use of pembrolizumab (Keytruda) or atezolizumab (Tecentriq) as monotherapy in clinical trials to treat patients with metastatic urothelial cancer (mUC) who have not received prior therapy and who have low expression of the protein programmed death ligand 1 (PD-L1).

In two ongoing clinical trials (KEYNOTE-361 and IMVIGOR-130), the Data Monitoring Committees’ early reviews found patients in the monotherapy arms of both trials with PD-L1 low status had decreased survival compared to patients who received cisplatin- or carboplatin-based chemotherapy.

Healthcare professionals should be aware that the populations enrolled in the ongoing clinical trials were eligible for platinum-containing chemotherapy, and therefore differ from those enrolled in the trials that led to the accelerated approvals of both Keytruda and Tecentriq in the treatment of patients with locally advanced or mUC who are not eligible for cisplatin-containing chemotherapy.

Both Keytruda and Tecentriq are currently approved by the FDA under accelerated approval for the treatment of patients with locally advanced or mUC who are not eligible for cisplatin-containing chemotherapy, irrespective of PD-L1 status. Keytruda and Tecentriq are also currently approved by the FDA for the treatment of multiple types of other cancers.

Patients should talk to their doctor if they have questions or concerns about either drug. Patients taking Keytruda or Tecentriq for other approved uses should continue to take their medication as directed by their healthcare professional.

FDA recommends providers select patients for the treatment of locally advanced or mUC using the criteria described in Section 14 of each label. These criteria supported the approvals for Keytruda and Tecentriq for initial monotherapy in cisplatin-ineligible patients.

Healthcare professionals and patients are encouraged to report adverse events or side effects related to the use of these products to the FDA's MedWatch Safety Information and Adverse Event Reporting Program.