* Files vemurafenib for regulatory approval
* Vemurafenib to treat deadliest form of skin cancer
* Analysts estimate peak sales of 500 mln-1 bln Swiss francs
* Roche shares up 0.8 pct, outperforms sector index
(Adds share price, analyst's comment, further details)
By Katie Reid
ZURICH, May 11 (Reuters) - Roche (ROG.VX) is seeking European and U.S. backing for vemurafenib, a drug to treat the deadliest form of skin cancer, the Swiss drugmaker said on Wednesday.
Analysts have estimated the drug, which Roche wants to use to treat patients with BRAF V600 mutation-positive metastatic melanoma, will have peak sales of 500 million to 1 billion Swiss francs ($0.5-1 billion).
Sentiment towards Roche is starting to improve thanks to a string of more positive product developments this year, helping to boost investors' confidence after they were rattled by development setbacks last year.
At 0847 GMT Roche's share price was 0.8 percent higher at 146.70 francs, outperforming a 0.4 percent rise in the Stoxx 600 Europe healthcare sector index .SXDP.
"We expect a smooth approval process given the high unmet medical need and the compelling efficacy data in a personalised treatment approach," Kepler Capital Markets analyst Martin Voegtli said.
Vemurafenib, a so-called BRAF inhibitor, is designed to selectively target and inhibit a mutated form of the BRAF protein found in about half of all cases of melanoma, the most aggressive form of skin cancer, killing around 40,000 people worldwide each year.
The world's largest maker of cancer drugs also said it had submitted an application for the cobas 4800 BRAF V600 Mutation Test, a companion diagnostic.
Once melanoma returns and spreads after initial treatment there are virtually no effective alternative treatments available.
The Roche drug and ipilimumab, an experimental drug for advanced melanoma being developed by U.S. group Bristol-Myers Squibb (BMY.N), promise new hope for patients who have so far had few options.
Roche had previously said it was aiming to file for approval of the medicine, which it has been developing with privately held Plexxikon, for approval in the second half and was hoping to launch the drug late next year or in early 2013.
The submissions are based on two studies.
The BRIM3 trial showed the drug helps patients live longer and also extends the period in which their disease does not get worse compared with those taking dacarbazine, the current standard of care, while the BRIM2 trial showed vemurafenib shrank tumours in 52 percent of trial participants.
Full data from the BRIM3 study and updated data from the BRIM2 trial will be presented at the annual meeting of the American Society of Clinical Oncology next month. ($1 = 0.9607 Swiss francs) (Editing by Dan Lalor and Greg Mahlich)