FDA approves Gamifant ( emapalumab-lzsg )

November 20, 2018, 

The U.S. Food and Drug Administration today approved Gamifant (emapalumab-lzsg) for the treatment of pediatric (newborn and above) and adult patients with primary hemophagocytic lymphohistiocytosis (HLH) who have refractory, recurrent or progressive disease or intolerance with conventional HLH therapy. This FDA approval is the first for a drug specifically for HLH.

"Primary HLH is a rare and life-threatening condition typically affecting children and this approval fills an unmet medical need for these patients," said Richard Pazdur, M.D., 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. "We are committed to continuing to expedite the development and review of therapies that offer meaningful treatment options for patients with rare conditions."

HLH is a condition in which the body’s immune cells do not work properly. The cells become overactive releasing molecules, which leads to inflammation. The immune cells start to damage the body’s own organs, including the liver, brain and bone marrow. It can be inherited, which is known as primary or “familial” HLH. It can also have non-inherited causes. People with primary HLH usually develop symptoms within the first months or years of life. Symptoms may include fever, enlarged liver or spleen and decreased number of blood cells.

The efficacy of Gamifant was studied in a clinical trial of 27 pediatric patients with suspected or confirmed primary HLH with either refractory, recurrent or progressive disease during conventional HLH therapy or who were intolerant of conventional HLH therapy. The median age of the patients in the trial was 1 year old. The study showed that 63 percent of patients experienced a response and 70 percent were able to proceed to stem cell transplant.

Common side effects reported by patients receiving Gamifant in clinical trials included infections, hypertension, infusion-related reactions, low potassium and fever. Patients receiving Gamifant should not receive any live vaccines and should be tested for latent tuberculosis. Patients should be closely monitored and treated promptly for infections while receiving Gamifant.

The FDA granted this application Priority Review and Breakthrough Therapy designation. Gamifant also received Orphan Drug designation, which provides incentives to assist and encourage the development of drugs for rare diseases.

DRUG TRIALS SNAPSHOT SUMMARY:

What is the drug for?

GAMIFANT is used to treat patients with primary hemophagocytic lymphohistiocytosis (HLH) who have been previously treated for the disease and whose disease

• has come back or progressed, or
• other medicines have not worked well enough or cannot be tolerated.

Primary HLH is an inherited form of HLH- a rare and life-threatening disorder. Patients with primary HLH have cells of the immune system called T and NK cells that don’t work properly causing too much inflammation.

How is this drug used?

GAMIFANT is an injection. It is given by a healthcare provider as an intravenous infusion (directly into blood stream) two times per week. It takes about 1 hour to receive GAMIFANT infusion.

What are the benefits of this drug?

After 8 weeks of treatment, sixty three percent of 27 patients achieved complete or partial improvement of HLH abnormalities.

Were there any differences in how well the drug worked in clinical trials among sex, race and age?

• Sex: Differences in how well GAMIFANT worked between males and females could not be determined because of the small number of patients.
• Race: The majority of patients in the clinical trial were White. Differences among races could not be determined due to small number of patients of other races.
• Age: Differences in how well GAMIFANT worked among age groups could not be determined because of the small number of patients per group.