Arena Pharma Awaits The 'Big' Day

Arena Lorcaserin 061212

Shares of Arena Pharmaceuticals Inc. (ARNA) have been setting new highs as investors warm up to the pending regulatory decision on the company's anti-obesity drug candidate Lorcaserin.

For readers who are new to Arena Pharma, here's a brief overview of the upcoming event...

Last month, an FDA panel, which reviewed the Lorcaserin NDA, voted 18 to 4, with one abstention, recommending approval, and concluding that the potential benefits of Lorcaserin outweigh the potential risks when used long-term in a population of overweight and obese individuals. The FDA is not required to follow the panel's advice, though it often does.

This is Lorcaserin's second go-around with the FDA. Arena was issued a Complete Response Letter, or CRL, for its Lorcaserin NDA in October 2010. The company was asked by the FDA to conduct various studies and analyses, and resubmit the NDA in order for the drug to be approved.

Accordingly, Arena resubmitted the Lorcaserin NDA in December 2011 after resolving the issues raised in the CRL. Lorcaserin intended for weight management, including weight loss and maintenance of weight loss, has a decision date set for June 27, 2012.

Lorcaserin is also under review in the European Union. The marketing authorization application for Lorcaserin was filed with the European Medicines Agency in March of this year and was subsequently accepted by the agency.

Eisai Inc. has exclusive rights to market and distribute Lorcaserin in most of North and South America, including the United States, Canada, Mexico and Brazil, subject to applicable regulatory approval.

Arena currently owns rights to Lorcaserin outside of North and South America, including in the European Union and Asia.

Arena shares, which touched a new high of $7.75 today, is currently trading at $7.66, up 8.34%.

The immediate contender in the race to find a cure for obesity is Vivus Inc.'s (VVUS) Qnexa.

The FDA was originally scheduled to rule on the resubmitted Qnexa NDA of Vivus on April 17, 2012. But following the company's submission of Risk Evaluation and Mitigation Strategy for Qnexa to the FDA on April 4, upon request, the regulatory agency deferred its decision by 3 months. The decision date for Qnexa is set for July 17.

Yet another anti-obesity drug under development is Orexigen Therapeutics Inc.'s (OREX) Contrave.

Orexigen's Contrave had also been at the FDA altar but was rejected by the regulatory agency in January of 2011, a month after an advisory committee voted 13 to 7, recommending approval of the drug. The company was asked to conduct a cardiovascular outcomes trial, or CVOT and resubmit the NDA for Contrave. Orexigen is conducting a double blind, randomized, placebo controlled CVOT under a Special Protocol Assessment with the FDA.

Obesity, a public health epidemic, is growing at an alarming rate. The CDC estimates that more than one-third of U.S. adults (35.7%) and about 17% (or 12.5 million) of children and adolescents aged 2-19 years are obese. According to a new report, 42 percent of Americans could be obese by 2030.

The drug therapy for treatment of obesity has had a checkered past, and till date, there has been no 'silver bullet' remedy for obesity.

A couple of approved diet drugs have been recalled, following reports of adverse side reactions like heart damage, and some of the investigational obesity drugs have gone belly-up like...

* Fen-phen, a combination drug of Phentermine and Fenfluramine, and a related drug Redux marketed by Wyeth were withdrawn from the U.S. market in September 1997 after the drugs were found to be associated with a serious heart condition known as valvular regurgitation, or leaky heart valves.

* In November 2008, Solvay Pharmaceuticals pulled the plug on its obesity compound SLV319, which was under phase II development, citing the stringent regulatory environment. According to the company, the discontinuation was not related to any adverse events or the efficacy of the compound.

* Considering the changing regulatory perspectives on the risk/benefit profile of the cannabinoid type 1 class of drugs, Pfizer Inc. (PFE) abandoned the development of CP-945598 (Otenabant) for weight management in November 2008. CP-945598, a selective antagonist of the cannabinoid type 1 receptor was in late-stage development when the company pulled the plug on the trial.

* Yet another investigational obesity drug, which was under phase III development, to bite the dust in 2008 was Merck's Taranabant. Merck halted development of the drug as it had too many side effects. Though Taranabant was considered a potential blockbuster, some analysts were wary of the drug's approval as it belonged to the same class as Sanofi-Aventis' (SNY) weight-loss drug Acomplia. In June 2007, the FDA rejected Acomplia saying that the drug's benefits did not outweigh its risks.

* The much-touted Acomplia, which was approved in the European Union in 2006, also had an abrupt end. The drug was withdrawn from the European markets in October of 2008 as it was linked to serious psychiatric disorders.

* In October 2010, Abbott Laboratories (ABT) withdrew its diet pill Meridia in the U.S. and Canada at the request of health regulators as the drug was found to increase the risk for heart attacks and strokes in a post-marketing study.

The market for anti-obesity drugs is virtually untapped. Roche's Xenical, a prescription anti-obesity drug and GlaxoSmithKline plc's (GSK) Alli, an over-the-counter weight-loss product are the two FDA-approved drugs for obesity on the market.

According to market research firm Global Industry Analysts Inc., the global market for anti-obesity drugs is projected to reach $10.3 billion by the year 2017.

Given the growing unmet demand and patients clamoring for a quick remedy, a really effective and safe weight-loss therapy is long overdue. Will Arena's Lorcaserin and Vivus' Qnexa reach the regulatory finish line this year? Stay tuned...

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