The U.S. Food and Drug Administration has approved the use of Arzerra (ofatumumab) given in combination with chlorambucil to treat patients with previously untreated chronic lymphocytic leukemia (CLL) for whom fludarabine-based therapy is considered inappropriate. Arzerra is a human monoclonal antibody that targets an epitope on the CD20 molecule encompassing parts of the small and large extracellular loops. The drug had been granted breakthrough therapy designation last year (OT 10/10/13 issue).
The drug's approval is based on results from a Phase III study of 447 patients with previously untreated CLL (and for whom fludarabine-based therapy was considered inappropriate by study investigators). The data showed a statistically significant improvement in median progression-free survival in patients who received Arzerra and chlorambucil compared with patients who received chlorambucil alone (22.4 months versus 13.1 months, respectively).
The most common adverse events for patients receiving Arzerra were neutropenia, asthenia, headache, leukopenia, herpes simplex, lower respiratory tract infection, arthralgia, and upper abdominal pain. Infusion reactions were seen in 67 percent of patients receiving Arzerra, 10 percent being grade three or higher.
Arzerra is being developed under a co-development and collaboration agreement between Genmab and GlaxoSmithKline.
In addition, the FDA gave Orphan Drug Status to volasertib for the treatment of acute myeloid leukemia (AML). The drug—an investigational inhibitor of polo-like kinase (Plk)—is currently being evaluated for safety and efficacy in a Phase III clinical trial for the treatment of patients who are 65 or older with previously untreated AML who are ineligible for intensive remission induction therapy.
The Orphan Drug designation—to encourage development of drugs in the diagnosis, prevention, or treatment of a medical condition affecting fewer than 200,000 people in the U.S.—grants a product market exclusivity for a seven-year period if the sponsor complies with certain FDA specifications, as well as tax credits and prescription drug user fee waivers. The designation does not, though, shorten the duration of the regulatory review and approval process.
American Cancer Society estimates project that about 18,860 new cases of AML will be diagnosed this year, with an average age at diagnosis of 66.
Volasertib (Boehringer Ingelheim Pharmaceuticals, Inc.) received the FDA's Breakthrough Therapy Designation in 2013 based on Phase I and II trial data (OT 10/25/13 issue), which is expected to be published later this year, according to a news release from the drug company.