FDA Expands Indication of ALL Treatment for Patients with Increased Relapse Risk

Officials with the FDA have expanded the approval of blinatumomab (Blincyto, Amgen) to include the treatment of adults and children with B-cell precursor acute lymphoblastic leukemia (ALL) who are in remission but still have minimal residual disease (MRD), according to a press release. This is the first FDA-approved treatment for patients with MRD-positive ALL.

Blinatumomab was first approved by the FDA under accelerated approval in December 2014 for the treatment of Philadelphia chromosome (Ph)-negative relapsed or refractory positive B-cell precursor ALL. Full approval was granted in July 2017, when the indication was also expanded to include patients with Philadelphia chromosome-positive ALL.

B-cell precursor ALL is a rapidly progressing type of cancer in which the bone marrow produces too many B-cell lymphocytes. The presence of MRD in patients who have achieved remission after initial treatment for this type of ALL indicates an increased risk of relapse.

According to the press release, blinatumomab works by attaching to the CD19 protein on leukemia cells and CD3 protein found on certain immune system cells.

The approval of this indication is based on a clinical trial that included 86 patients in first or second complete remission who had detectable MRD in at least 1 out of 1000 cells in their bone marrow. Overall, undetectable MRD was achieved by 70 patients after 1 cycle of treatment with blinatumomab and more than half of the patients remained alive and in remission for at least 22.3 months.

Adverse effects associated with blinatumomab include infections, fever, headache, infusion-related reactions, low levels of certain blood cells, febrile neutropenia, and low levels of platelets in the blood.

Blinatumomab carries a boxed warning alerting patients and health care providers that some clinical trial participants had problems with low blood pressure and difficulty breathing at the start of the first treatment, experienced a short period of difficulty with thinking, or other adverse effects in the nervous system. Additionally, there is a risk of serious adverse reactions in pediatric patients due to benzyl alcohol preservative. The drug should be prepared with preservative-free saline for patients weighing less than 22 kilograms, according to the FDA.

This new indication was approved under the accelerated approval pathway. Further study in clinical trials is required to verify that achieving undetectable MRD with blinatumomab improves survival or disease-free survival in patients with ALL.

Originally published by Specialty Pharmacy Times.

Reference

• FDA expands approval of Blincyto for treatment of a type of leukemia in patients who have a certain risk factor for relapse [news release]. FDA’s website. https://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm603151.htm?utm_campaign=03292018_Approval_Blincyto&utm_medium=email&utm_source=Eloqua Accessed March 29, 2018.