Merck KGaA has completed enrolment in a late-stage trial of its investigational brain tumour drug cilengitide.

The German group's Merck Serono division says more than 500 patients have been successfully recruited into the Phase III trial, the primary endpoint of which is overall survival. The study will assess cilengitide, an integrin inhibitor, in combination with standard treatment in a biomarker-defined subgroup of newly-diagnosed patients with glioblastoma (GBM).

Oliver Kisker, head of oncology at Merck Serono, said completing patient enrollment "is a very exciting milestone for us and takes us a step closer to evaluating the efficacy and safety of cilengitide in patients with this aggressive form of brain cancer, an area of high unmet medical need".

In Europe, two to three people in 100,000 develop glioblastoma each year, while in the USA about three new cases per 100,000 are reported annually. Though rare, GBM is the most aggressive form of primary brain tumours and has a poor prognosis in adults with a two-year overall survival rate of 27.2% with standard of care treatment (radiotherapy plus temozolomide).

Cilengitide is also being investigated in early-stage trials for non-small cell lung cancer and squamous cell carcinoma of the head and neck.

Link-up with Affectis

Meantime, Merck has signed an exclusive licensing agreement with Germany's Affectis Pharmaceuticals for the development of oral compounds targeting P2X7 receptors, which are believed to be involved in neuroinflammation observed in some neurodegenerative diseases.

Under the terms of the deal, Affectis will receive 2.4 million euros in upfront payment and research funding, and could pocket up to 277 million euros in milestones for the first three products to come out of the collaboration, plus royalties.

P2X7 is an adenosine triphosphate-gated ion channel receptor which is essential for the maturation and release of the pro-inflammatory cytokines. It is found on brain cells, which are activated by high levels of ATP in conditions of neuroinflammation.