FDA Grants Priority Review to Leukemia Drug

The FDA recently granted priority review for Amgen’s supplemental Biologics License Application (sBLA) for blinatumomab (Blincyto) to include data showing it can treat Philadelphia chromosome-negative (Ph-) relapsed or refractory B-cell precursor acute lymphoblastic leukemia (ALL) in patients less than 18 years old.

"Children and adolescents with ALL who experience a second or greater relapse or are refractory often have a dismal prognosis with survival rates below 10 percent," said Sean E. Harper, MD, executive vice president of Research and Development at Amgen. "The FDA's acceptance of the sBLA submission for Blincyto reinforces immunotherapy as a potential option for children in need of new treatments to fight this complex disease and help prevent further relapse."

According to Amgen, the sBLA is based on findings from a phase 1 and 2 single-arm trial that included 70 patients younger than 18 years with relapsed or refractory B-cell precursor ALL.

Patients enrolled this trial also previously relapsed at least twice or relapsed after an allogeneic hematopoietic stem cell transplant (alloHSCT), according to the study.

Phase 1 revolved around dose-finding with a primary endpoint finding the maximum-tolerated dose where only 1 or less patients received a dose-limiting toxicity. Researchers also stated that the secondary endpoints were pharmacokinetics and incidence of adverse events.

Phase 2 evaluated the safety and efficacy of the dose established in phase 1. The primary endpoint was remission within 2 treatments, while secondary endpoints included incidences of adverse events, proportion undergoing alloHSCT after treatment, relapse-free survival, and overall survival.

In both phases, minimal residual disease response and complete minimal disease response were exploratory endpoints.

The most frequent adverse reaction observed were anemia, thrombocytopenia, febrile neutropenia, hypokalemia, and neutropenia.