GlaxoSmithKline/Genmab's leukaemia drug ofatumumab (marketed as Arzerra) has hit a setback after failing to meet targets in a late-stage trial assessing its potential in patients with B-cell lymphoma.

GSK said it is now unlikely that ofatumumab will be filed for this indication, given that a combination of the drug plus chemotherapy failed to outperform a rituxan/chemotherapy combo on progression free survival in patients with relapsed/refractory diffuse large B-cell lymphoma, the most common form of non-Hodgkin lymphoma (NHL).

Also, while the 447-patient Phase III trial showed no differences between the two treatment groups in adverse events leading to treatment discontinuation, or severe or fatal ones, there were more dose interruptions and delays due to infusion reactions and increased serum creatinine in the ofatumumab arm "which require further analysis," the firm added.

“We are disappointed that the ORCHARRD study did not meet its primary endpoint," Rafael Amado, Head of Oncology R&D, GSK, said in a statement, adding that more detailed data from the study will be presented at a medical conference later this year, "which we hope will provide further clarity" on the headline results.

Arzerra is a monoclonal antibody that causes the body’s immune response to fight against normal and cancerous B-cells. 

The drug was first given a green light by the US FDA in 2009 for the treatment of patients with chronic lymphocytic leukaemia (CLL) who have not responded to Genzyme’s Campath (alemtuzumab) or the chemotherapy fludarabine, and more recently for patients who have not received prior therapy and for whom fludarabine-based therapy is considered inappropriate.