GSK and Genmab’s Phase III trial of CLL drug ofatumumab fails to meet primary endpoint

29th June 2014 (Last Updated June 29th, 2014 18:30)

GlaxoSmithKline (GSK) and Genmab have reported results from the Phase III trial of ofatumumab (Arzerra) versus physicians' choice in patients with bulky fludarabine-refractory chronic lymphocytic leukaemia (CLL).

GlaxoSmithKline HQ

GlaxoSmithKline (GSK) and Genmab have reported results from the Phase III trial of ofatumumab (Arzerra) versus physicians' choice in patients with bulky fludarabine-refractory chronic lymphocytic leukaemia (CLL).

In the trial, a total of 122 patients with bulky fludarabine-refractory CLL were randomised to one of two treatment arms either ofatumumab or physicians' choice (2:1).

The open-label Phase III trial failed to meet its primary endpoint of progression free survival (PFS), as the median PFS was 5.36 months for ofatumumab and 3.61 months for physicians' choice.

The trial was carried out to meet requirements from the EU Commission for the conditional approval of ofatumumab to treat CLL in patients who are refractory to fludarabine and alemtuzumab.

According to the companies, the result reported was headline data and the full analysis of safety and efficacy data is underway, which is scheduled to be completed in the coming months.

"Based on this result, we do not anticipate applying for a label expansion for ofatumumab in this specific refractory CLL population."

Genmab chief executive officer Jan van de Winkel said: "Although ofatumumab performed broadly in-line with previous data, the result is disappointing.

"Based on this result, we do not anticipate applying for a label expansion for ofatumumab in this specific refractory CLL population."

In the trial, patients randomised to ofatumumab received an initial dose of 300mg, followed one week later by 2,000mg once-weekly for seven weeks, followed four weeks later by one infusion of 2,000mg every four weeks for a total treatment duration of six to 12 months.

The company said that patients in the physicians' choice arm were given a treatment regimen selected by a physician for up to six months.

The trial's primary endpoint was PFS as adjudicated by the Independent Review Committee, while the secondary objectives are to assess response, overall survival, safety, tolerability and health-related quality of life of subjects treated with ofatumumab versus physicians' choice of treatment.


Image: GlaxoSmithKline headquaters in London, UK. Photo: courtesy of Maxwell Hamilton.