Drug for Treating Rare, Aggressive Cancer Receives FDA Approval

The FDA has approved tagraxofusp-erzs (Elzonris, Stemline Therapeutics) infusion for the treatment of blastic plasmacytoid dendritic cell neoplasm (BPDCN) in adults and in pediatric patients, aged 2 years and older.

BPDCN is an aggressive and rare disease of the bone marrow and blood that can affect multiple organs, including the lymph nodes and the skin. It often presents as leukemia or evolves into acute leukemia. The disease is more common in men than women and in patients 60 years and older.

Stemline's application for tagraxofusp-erzs was granted Breakthrough Therapy and Priority Review designations by the FDA. The product also received Orphan Drug designation.

“Prior to today’s approval, there had been no FDA approved therapies for BPDCN. The standard of care has been intensive chemotherapy followed by bone marrow transplantation. Many patients with BPDCN are unable to tolerate this intensive therapy, so there is an urgent need for alternative treatment options,” said Richard Pazdur, MD, director of the FDA’s Oncology Center of Excellence and acting director of the Office of Hematology and Oncology Products in the FDA’s Center for Drug Evaluation and Research, in a prepared statement.

The efficacy of Elzonris was studied in 2 cohorts of patients in a single-arm clinical trial. The first trial cohort enrolled 13 patients with untreated BPDCN, and 7 of those patients achieved complete remission (CR) or CR with a skin abnormality not indicative of active disease (CRc). The second cohort included 15 patients with relapsed or refractory BPDCN. One patient achieved CR and 1 patient achieved CRc.

Common adverse effects reported by patients in clinical trials were capillary leak syndrome, nausea, fatigue, swelling of legs and hands, fever, chills and weight increase. Most common laboratory abnormalities were decreases in lymphocytes, albumin, platelets, hemoglobin, and calcium, and increases in glucose and liver enzymes (ALT and AST). According to the FDA, health care providers are advised to monitor liver enzyme levels and for signs of intolerance to the infusion. Women who are pregnant or breastfeeding should not take Elzonris because it may cause harm to a developing fetus or newborn baby.

The labeling for Elzonris contains a Boxed Warning to alert health care professionals and patients about the increased risk of capillary leak syndrome which may be life-threatening or fatal to patients in treatment.

Additional information is available at our sister publication OncLive.com.

Reference

FDA approves first treatment for rare blood disease [news release]. Silver Spring, MD; December 21, 2018: FDA website. https://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm629020.htm?rel=0" . Accessed December 21, 2018.