The world's top anti-cancer pharmaceutical company, Roche Holding AG, posted the biggest gains Zurich trading since February after new studies on its tumor drug Avastin proved it would be able to hold its own against rival Erbitux.

Roche rose 4.5 percent to $180.0575, its biggest gain since Feb. 25.

``Data in lung cancer suggests very limited competition to Avastin,'' Merrill Lynch-London analyst Graham Parry, was quoted by Bloomberg telling clients on Monday.

Rival drug company Merck was said to have released data saying its drug Erbitux wouldnot threaten Avastin'shold in the cancer market.

Moreover, ROche presented new findings from its clinical trials of Avastin at an American Society of Clinical Oncology meeting in Chicago over the weekend. Roche said the new studies showed that Avastin helped extend the lives of patients with colorectal cancer by about two years.

Another round of tests showed that increasing dosage of Avastin could slow down the growth of breast tumors.

Avastin was developed by Genentech Inc.,where Roche is the majority stakeholder. Shares of Genentech jumped to $72.65 in Frankfurt after closing at $70.87 in New York Stock Exchange composite trading on May 30.