BioMarin and its patient coaches are ready to roll on Vimizim launch

BioMarin Pharmaceuticals ($BMRN) nabbed the FDA's blessing for Vimizim, the only drug ever approved to treat a rare enzyme disorder called Morquio A syndrome. That's the good news. The not-so-good news is that Vimizim will wear a boxed warning about the risk of anaphylaxis. But in any case, the FDA nod could set the M&A rumor mill to work again.

According to the FDA, only about 800 patients in the U.S. have Morquio A syndrome, an enzyme deficiency that causes joint abnormalities and other bone problems, as well as hearing loss and heart problems. It's a painful, disfiguring condition; patients often suffer through multiple surgeries, and they tend to die young.

But even at 800 U.S. patients--3,000 in the developed world, according to BioMarin--Vimizim could rack up hundreds of millions in sales. Pricing is bound to be hefty. Rare disease drugs are among the priciest on the market, and several of BioMarin's other products bear 6-figure price tags. And with no other treatments in the market, analysts figure Vimizim (elosulfase alfa) could reach at least $500 million in sales--even as much as $800 million. That's significant for BioMarin, which reported $400 million in sales for the first 9 months of 2013.

The Novato, California, company's shares dropped on the approval news, however, partly on worries about the boxed warning. For patients with few options, the risk of anaphylaxis may not be much of a deterrent. The danger, to BioMarin at least, may be that fewer patients end up being able to tolerate the drug, and that would put a damper on Vimizim's sales prospects. In clinical trials, the allergic reactions happened during Vimizim infusions, FDA said. That might help defuse patients' initial concern, because treatment could be immediate if a patient did suffer a reaction.

BioMarin has a support organization that pairs case managers with patients, to help with insurance and payment. That's pretty much de rigueur for companies marketing rare-disease treatments. BioMarin's support team "will help patients obtain coverage and minimize out-of-pocket expenses and find alternative financial assistance for treatment," the company said in a statement.

BioMarin's expertise in the rare-disease drugs field has made it a perennial entry on biotech's list of hot buyout prospects. Last fall, the story was that Roche ($RHHBY) was eyeing BioMarin for a $13 billion-plus buyout. When Vimizim won a 20-1 vote from an FDA advisory panel in November, the buzz intensified, with market watchers bandying about several ideas for potential suitors, including Sanofi ($SNY), whose Genzyme unit also develops and markets drugs for rare enzyme disorders. With shares trading at about $76, however, BioMarin could be too expensive for pharma dealmakers.

- read the FDA statement

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