Breakthrough Designation Granted to Daratumumab for Double Refractory Multiple Myeloma

Peter F. Lebowitz, MD, PhD

An investigational monoclonal antibody called daratumumab has received breakthrough therapy designation from the FDA for the treatment of patients with double refractory multiple myeloma, according to a statement from the drug’s manufacturer, Janssen Biotech.

Daratumumab is an investigational human CD38 monoclonal antibody. The CD38 molecule is highly expressed on the surface of multiple myeloma cells, as well as in other tumor types. The drug is currently in phase I/II studies for multiple myeloma patients. The FDA is considering its use in patients who have failed at least three lines of prior therapy, including a proteasome inhibitor and an immunomodulatory agent, as well as patients who are refractory to both types of therapy.

Preliminary efficacy data from a phase I/II dose-escalation study involving daratumumab were presented at the 54th Annual Meeting of the American Society of Hematology in Atlanta, Georgia, in December 2012. The data were based on 32 patients with relapsed multiple myeloma who received daratumumab in doses up to 24 mg/kg, the highest and final dose level in the study. Of the patients who received that level of daratumumab, two achieved a partial response and one achieved a minimal response. Of the 12 patients who received 4 mg/kg of daratumumab or higher, eight achieved at least a minimal response. No major safety issues were identified, and the most relevant drug-related adverse events included low-grade infusion-related reactions and a temporary drop in the level of natural killer cells.

The FDA can assign breakthrough designation to drugs that are designed to treat a life-threatening condition and appear to be superior to existing treatments. The designation creates an expedited review process for the drug by allowing for more meetings between the FDA and the manufacturer during the development process, as well as requiring fewer patients for clinical trials and reducing the amount of time required for these trials. Janssen can still choose to submit daratumumab for fast-track designation, accelerated approval, and priority review.

“We are honored that the FDA has granted Breakthrough Therapy Designation to another compound in our pipeline,” said Peter F. Lebowitz, MD, PhD, head of Global Oncology Therapeutic Area at Janssen, in a statement. “Our team is looking forward to the opportunity to work closely with the FDA on the development program of this compound, which has the potential to make a difference in the lives of patients.”

Plesner T, Lokhorst H, Gimsing P, et al. Daratumumab, a CD38 monoclonal antibody in patients with multiple myeloma — data from a dose escalation phase I/II study. Presented at: 54th ASH Annual Meeting; December 8-11, 2012; Atlanta, GA. Abstract 73.