German healthcare company Merck expects to get a long-term boost from study results in June that showed its main cancer drug Erbitux has an edge over rival product Avastin.

Erbitux, which accounted for roughly 8 % of Merck's €10.7 billion in sales last year, in June was shown to be more effective at prolonging the lives of colorectal cancer patients than Roche's Avastin.

Only patients whose tumours contain the non-mutated version of a gene called KRAS took part in the trial. Erbitux is only approved in this patient subgroup, which accounts for about 60 % of colorectal cancer cases.

"We still have room to grow in colorectal cancer due to our personalised KRAS-approach," Belen Garijo, the head of Merck's prescription drugs division said.

She said the study results would help her marketing teams argue the case for Erbitux, which unlike Avastin, requires doctors to perform a genetic test on the cancer tissue before starting therapy.

Merck has the marketing and development rights to Erbitux outside North America, while Bristol-Myers Squibb sells the product in North America with Eli Lilly receiving royalties.