FDA Approves New Treatment for Mantle Cell Lymphoma

Calquence demonstrated favorable overall response rate in initial studies

The FDA has granted accelerated approval to acalabrutinib (Calquence, AstraZeneca) for the treatment of adults with mantle cell lymphoma who have received at least one prior therapy.

“Mantle cell lymphoma is a particularly aggressive cancer,” 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. “For patients who have not responded to treatment or have relapsed, Calquence provides a new treatment option that has shown high rates of response for some patients in initial studies.”

Mantle cell lymphoma is a rare and fast-growing type of non-Hodgkin’s lymphoma. According to the National Cancer Institute, it represents 3% to 10% of all non-Hodgkin’s lymphoma cases in the U.S. Mantle cell lymphoma is a cancer of the lymph system, a part of the body’s immune system made up of lymph tissue, lymph nodes, the spleen, thymus, tonsils, and bone marrow. By the time mantle cell lymphoma is diagnosed, it usually has spread to the lymph nodes, bone marrow, and other organs.

Acalabrutinib is a kinase inhibitor that works by blocking an enzyme needed by the cancer to multiply and spread.

Acalabrutinib was approved using the FDA’s accelerated approval pathway, under which the agency may approve drugs for serious conditions where there is unmet medical need and a drug is shown to have certain effects that are reasonably likely to predict a clinical benefit to patients. Further study is required to verify and describe anticipated clinical benefits of acalabrutinib, and the sponsor is currently conducting this trial.

This accelerated approval of acalabrutinib was based on data from a single-arm trial that included 124 patients with mantle cell lymphoma who had received at least one prior treatment. The trial measured how many patients experienced complete or partial shrinkage of their tumors after treatment (overall response rate). In the trial, 81% of patients had a complete or partial response (40% complete response, 41% partial response).

Common side effects of acalabrutinib include headache; diarrhea; bruising; fatigue and myalgia; and anemia, thrombocytopenia, and neutropenia.

Serious side effects include bleeding (hemorrhage), infections, and irregular heartbeat (atrial fibrillation). Additional cancers, known as second primary malignancies, have occurred in some patients taking acalabrutinib. Women who are breastfeeding should not take acalabrutinib because it may cause harm to a newborn baby.

The FDA granted this application priority review and breakthrough therapy designations. Acalabrutinib also received an orphan drug designation, which provides incentives to assist and encourage the development of drugs for rare diseases.

Source: FDA; October 31, 2017.