FDA Warns Against Idelalisib

Idelalisib has presented serious adverse events in combination trials in both the US and Europe.

Following reports of an increased rate of adverse events (AEs), including deaths, in clinical trials that include the use of idelalisib (Zydelig) in combination with other cancer medicines, the FDA has alerted healthcare providers, and is reviewing the trial findings. The drug’s developer, Gilead Sciences, Inc, will be halting 6 clinical trials in patients with chronic lymphocytic leukemia (CLL), small lymphocytic lymphoma (SLL), and indolent non-Hodgkin lymphomas (NHL).

Zydelig is currently approved by the FDA for the treatment of:

  • Relapsed CLL, in combination with rituximab, in patients for whom rituximab alone would be considered appropriate therapy due to other comorbidities.
  • Relapsed follicular B-cell NHL in patients who have received at least 2 prior systemic therapies.
  • Relapsed SLL in patients who have received at least 2 prior systemic therapies.

The drug is also being reviewed by the European Medicine Agency (EMA) following reports of increased rate of serious AEs, primarily due to infections, in trials that were evaluating idelalisib in combination with other cancer drugs. The EMA has asked that patients be closely monitored, and treatment should continue if patients tolerate the drug.