This story was originally published May 18, 2018. As part of 51˶'s year-end review of the year's news, we are republishing it along with an update on what has happened following the FDA's alert.
WASHINGTON -- Pembrolizumab (Keytruda) or atezolizumab (Tecentriq) monotherapy for certain patients with advanced or metastatic urothelial carcinoma were each associated with decreased survival compared with chemotherapy, the Friday.
The data safety and monitoring committees of two trials reported the decreased survival in patients with low expression levels of programmed death ligand 1 (PD-L1) who were treated with either of these agents as monotherapy.
Both trials -- KEYNOTE-361 (Merck) and IMVIGOR-130 (Genentech) -- have stopped enrolling such patients.
"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," the FDA stated.
KEYNOTE-361 is studying pembrolizumab with or without chemotherapy (cisplatin plus gemcitabine or carboplatin plus gemcitabine).
IMVIGOR-130 is studying atezolizumab with or without chemotherapy (cisplatin plus gemcitabine or carboplatin plus gemcitabine) in untreated patients.
The combination and chemotherapy-alone arms will remain open in both trials. Each trial also has a monotherapy arm for each respective immunotherapy, which will remain open only to patients with high levels of PD-L1 expression.
Both drugs are currently approved, irrespective of PD-L1 status, for the treatment of locally advanced or metastatic urothelial carcinoma in patients ineligible for cisplatin-containing chemotherapy. Urothelial carcinoma accounts for about 90% of all bladder cancers in the U.S.
In 2016, atezolizumab became the first PD-L1 inhibitor to gain approval in bladder cancer, indicated for patients with locally advanced or metastatic urothelial carcinoma who had progressed during or after platinum-based chemotherapy, or within 12 months of receiving either neoadjuvant or adjuvant platinum-based chemotherapy.
In 2017, the for this same patient population.
"FDA recommends providers select patients for the treatment of locally advanced or metastatic urothelial cancer using the criteria described in Section 14 of each label," the agency said. "These criteria supported the approvals for Keytruda and Tecentriq for initial monotherapy in cisplatin-ineligible patients."
The FDA noted that patients taking either of these immunotherapies for other cancer types should continue to take their medication as directed by their healthcare professional, but requested that any adverse events be reported to the agency's MedWatch Adverse Event Reporting program.