PARIS (Reuters) - Sanofi SA has won U.S. approval for its multiple sclerosis (MS) pill Aubagio, one of the two treatments for the chronic disease that could return the French drugmaker to growth after several blockbuster drugs lost patent protection.
The drug is less effective than rival pills but has milder side effects and analysts say it could be popular among newly diagnosed patients. Around 35 to 40 percent of MS sufferers prefer to take no medication rather than face unwanted side effects.
Sanofi is also expected to highlight the convenience of a once-daily pill against injectable drugs that are widely prescribed as a first-line treatment for MS.
"If you look at the multiple sclerosis market, which is worth $12 billion and is currently dominated by injectables, and introduce a pill with similar efficacy, the prospects are very bright," Bill Sibold, head of MS at Sanofi's rare disease unit Genzyme, told Reuters.
Aubagio is expected to launch on the U.S. market in a few weeks, a spokeswoman for Sanofi unit Genzyme said.
The medicine will cost $45,000 for a year's treatment, making it cheaper than rivals and indicating Sanofi is ready for a commercial battle to win market share.
Novartis AG's Gilenya - the only other MS pill currently on the market - costs 28 percent more, while injectable treatments such as Biogen Idec Inc's Avonex and Teva Pharmaceutical Industries Ltd's Copaxone are 8 and 6.5 percent higher respectively.
Deutsche Bank analysts said the U.S. green light for Aubagio indicated Sanofi could deliver new drugs from its late-stage pipeline but expectations for the medicine were not particularly high, given its modest efficacy.
Aubagio reduced the risk of MS relapses by about 30 percent in clinical tests, which is comparable to the efficacy of the older injectable drugs but less potent than either Gilenya, which showed a reduction of over 50 percent, or Biogen's experimental product BG-12.
Shares in Sanofi were 0.5 percent lower by 1438 GMT on Thursday, outperforming the CAC40 index, which was down 1 percent. Analysts said many investors had been anticipating U.S. approval for Aubagio in recent days.
Multiple sclerosis is a chronic, often disabling disease that attacks the central nervous system and can lead to numbness, paralysis and loss of vision. It affects 2.5 million people worldwide and has no cure.
Gilenya and Biogen's BG-12 are widely expected to dominate the market that JPMorgan analysts see growing to $14 billion in 2015 from $9.6 billion last year.
Aubagio is likely to grab a relatively small chunk of this market, with worldwide sales expected to reach around $400 million in 2016, according to consensus forecasts compiled by Thomson Reuters Pharma.
Cheuvreux analyst Marcel Brand, who has a more optimistic forecast, predicts peak sales of Aubagio of 1.48 billion euros ($1.91 billion) by 2018.
Helvea analyst Odile Rundquist is forecasting sales of 1 billion euros based on Aubagio's milder side effects and convenience of a once-daily dose. This would favour Aubagio once Biogen's BG-12, a pill that is taken three times a day, arrives on the market.
European regulators are expected to give their response to Aubagio in the first quarter of 2013.
As well as Aubagio, Sanofi has filed for approval for MS injectable drug Lemtrada and has other multiple sclerosis treatments in early-stage development.
Sanofi is also looking to acquire promising MS treatments being developed by other companies.
The most common side effects associated with Aubagio include increased levels of the enzyme alanine transaminase, which can indicate damage to the liver, as well as hair loss, diarrhea, influenza, nausea and numbness of the skin, Sanofi said.
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Additional reporting by Tej Sapru, Sunayan Bhattacharjee and Ben Hirschler; Editing by David Cowell