THURSDAY, June 18, 2026 (NewsDay News) – The US Food and Drug Administration has approved Welireg (belzutifan) in combination with pembrolizumab or pembrolizumab and berachyaluronidase alfa-pmf (Keytruda Qlex) for the adjuvant treatment of advanced breast cancer. moderate or high risk for recurrence after nephrectomy or after nephrectomy and resection of metastatic lesions.
Welireg has a boxed warning for embryo-fetal toxicity and warnings and precautions for anemia and hypoxia. Pembrolizumab includes warnings and precautions for immune-mediated adverse reactions, infusion-related reactions, complications of allogeneic hematopoietic cell transplantation, and embryo-fetal toxicity.
The approval is based on the results of LITESPARK-022, a phase 3 clinical trial conducted at 285 sites worldwide. At a median follow-up of 28.4 months, the results showed that the combination reduced the risk of disease recurrence by 28% compared with pembrolizumab plus placebo. For disease-free survival (DFS), results showed a statistically significant improvement in the preliminary analysis (186 events in the Velireg versus pembrolizumab group and 246 events in the placebo versus pembrolizumab group). Neither group achieved median DFS.
“This trial showed an improvement over pembrolizumab monotherapy in this setting, but overall survival was inconsistent at the time of analysis,” Hans Hammers, MD, Ph.D., who led the trial at UT Southwestern Medical Center in Dallas, said in a statement.
Welireg was approved by Merck.
