The FDA granted accelerated approval to umbralisib in February 2021 for patients with two types of lymphoma: Adults with relapsed or refractory marginal zone lymphoma who received at least one prior therapy, and those with relapsed or refractory follicular lymphoma who received at least three prior therapies.
According to the FDA, the possible increased risk of death arose from early findings in a phase 3 trial evaluating the drug in a related type of cancer: chronic lymphocytic leukemia.
“Because of the seriousness of this safety concern and the similarities between the two types of cancer for which this drug is approved and the type of cancer that was studied in the clinical trial, we are alerting patients and health care professionals that we are reevaluating this risk against the benefits of Ukoniq [umbralisib] for its approved uses,” the FDA safety communication states.
The FDA said it performed an initial review of data from the phase 3, randomized controlled UNITY trial, which is evaluating the efficacy of umbralisib plus a monoclonal antibody in patients with chronic lymphocytic leukemia.
“The results showed a possible increased risk of death in patients receiving the combination of Ukoniq [umbralisib] and the monoclonal antibody compared to the control arm,” according to the FDA. “Those receiving the combination of Ukoniq [umbralisib] and the monoclonal antibody also experienced more serious adverse events than those in the control arm.”
Although the drug has not been approved for patients with chronic lymphocytic leukemia, the FDA believes the findings could “have implications for its approved uses” in marginal zone lymphoma and follicular lymphoma.
However, the phase 2 trial that led to February 2021 approvals found the drug’s safety profile to be “manageable,” with serious adverse reactions reported in 18% of patients receiving the dual oral inhibitor of phosphoinositide 3 kinase delta and casein kinase 1 epsilon. These adverse reactions included diarrhea-colitis (4%), pneumonia (3%), sepsis (2%), and urinary tract infection (2%); however, no elevated risk of death was indicated in that analysis.
The FDA noted it will continue to evaluate the results from the phase 3 UNITY trial in chronic lymphocytic leukemia and has suspended enrollment of new patients in other ongoing clinical trials of the drug.
The FDA stated that it would communicate its “final conclusions and recommendations when we have completed our review.” In the meantime, the agency asks health care professionals to review how patients receiving umbralisib are faring and discuss “the risks and benefits of continuing” versus switching to other treatments.
The FDA also asks clinicians and patients to report side effects involving the drug to the FDA MedWatch program.
A version of this article first appeared on Medscape.com.