French-based Innate Pharma has failed to meet the primary efficacy endpoint in the Phase II clinical trial (EffiKIR) of lirilumab to treat patients with acute myeloid leukaemia (AML).
Lirilumab is a fully human monoclonal antibody developed as a checkpoint inhibitor to block the interaction between KIR2DL-1,KIR2DL-2 and KIR2DL-3 inhibitory receptors and their ligands, resulting in the activation of NK cells and destruction of tumour cells.
The double-blinded, placebo-controlled, randomised Phase II trial was designed to evaluate lirilumab as a single agent maintenance treatment in 150 elderly patients with AML in first complete remission.
While the primary efficacy endpoint of leukaemia-free survival (LFS) was not met, the study is able to confirm the safety profile of the drug as a monotherapy.
Innate Pharma chief medical officer Pierre Dodion said: "Although we knew that this setting was challenging, we are disappointed by the results of the EffiKIR study and will investigate further to better understand the data in its entirety.
"Lirilumab is tested in a broad and comprehensive combination programme in multiple indications and we saw encouraging early efficacy signals of lirilumab in combination with nivolumab at the 2016 SITC meeting."
The top-line results from the EffiKIR trial showed that there was no statistical difference between the lirilumab arms and the placebo arm on the LFS or other efficacy endpoints.
The adverse events were found to be consistent with the previously reported safety profile of lirilumab.
Lirilumab is being evaluated further by its licensee Bristol-Myers Squibb in combination with other agents to treat a variety of tumour types.