UPDATE 1-Eisai nausea drug gets U.S. additional use approval

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By Edwina Gibbs

TOKYO, March 3 (Reuters) - Japanese drug maker Eisai Co Ltd (4523.T) said on Monday U.S. regulators approved nausea treatment Aloxi to prevent vomiting after surgery -- its first approval for a drug from recently acquired cancer specialist MGI Pharma.

MGI Pharma's product line-up has taken on added importance for Japan's fourth-largest drug maker after recent drug setbacks including a Parkinson's disease medicine which failed to meet its key goal in a late-stage trial and the loss of an opportunity to win an early approval for a cancer drug.

Aloxi has been on the market in the United States since 2003 to treat chemotherapy-induced nausea and Eisai expects Aloxi to produce sales of $550 million to $600 million for both indications combined in the business year starting April 2011, up from around $230 million in calendar 2007.

Around 90 percent of those sales will come from chemotherapy-induced nausea prevention, where Aloxi currently has a 40 percent market share, as competitors' products are not being aggressively promoted.

"There is a large market opportunity for us," Lonnie Moulder, vice chairman of Eisai's North American operations, told a news conference.

Aloxi competes with GlaxoSmithKline's (GSK.L) Zofran and Roche's (ROG.VX) Kytril, which are now off-patent, as well as Sanofi-Aventis's (SASY.PA) Anzemet.

Eisai is also seeking approval for an oral capsule formulation of the drug and the Food and Drug Administration may hand down a decision in August.

The marketing and distribution rights for Aloxi were licensed from Swedish firm Helsinn Healthcare.

Eisai is also hoping to win approval for another MGI Pharma drug this year -- Aquavan, a sedative that can be administered by non-anaesthesiologists.

The drug maker also said on Monday it had received approval in Japan for its Vasolan tablets to be used to treat atrial fibrillation, or irregular heartbeat, in addition to coronary heart disease.

The statements follow news at the weekend that U.S. regulators have granted priority review for Eisai's Aciphex acid reflux drug to also be used in patients aged 12 to 16.

A priority review means the Food and Drug Administration (FDA) is likely to decide within six months whether to approve the treatment, rather than the usual 10-month review period.

Eisai shares closed down 3.2 percent at 3,660 yen, compared with a 4.5 percent fall for the benchmark Nikkei index .N225. (Additonal reporting by Jessica Hall in Philadelphia; Editing by Louise Ireland)