Experimental Multiple Myeloma Drug Safe and Effective in Trials

Daratumumab monotherapy slows disease progression a year after treatment.

An investigational drug for multiple myeloma may soon offer a much needed treatment option for patients with the disease.

A study published in the New England Journal of Medicine reported promising results from an initial phase 1/2 trial evaluating daratumumab monotherapy in patients with relapsed or refractory multiple myeloma. Of these patients, 64% were refractory to the current multiple myeloma standard of care treatments with proteasome inhibitors and immunomodulatory drugs.

Part 1 of the trial enrolled 32 patients in a dose-escalation study of weekly doses of daratumumab between 0.005 and 24 mg/kg. Part 2 included 72 patients who received 16 mg/kg daratumumab. Patients treated with 16 mg/kg of daratumumab had a median of 4 previous lines of therapy.

The results of the trial showed a 36% response rate among patients in the group receiving 16 mg/kg of daratumumab, with responses to the drug deepening over time, the researchers wrote. Twelve months after the start of treatment, 65% of the patients who responded to treatment were still progression-free.

The most common adverse events associated with daratumumab were pneumonia and thrombocytopenia. Reactions were mild and there were no dose-dependent adverse events. Additionally, there was no maximum tolerated dose identified up to 24 mg/kg during part 1 of the trial.

"Patients who have relapsed or refractory multiple myeloma currently have very limited treatment options,” said Jan van de Winkel, PhD, chief executive officer of Genmab. “The results from this first-in-human study of daratumumab, presented in full in The NEJM, show an impressive response rate and duration of response, particularly when you consider that patients in the study had received a large number of prior treatments."