US FDA says Shire's Vyvanse was properly granted five-year market exclusivity

The US Food and Drug Administration, following a thorough administrative review of governing statutory and regulatory standards and public comments, has affirmed its prior decision to grant five-year New Chemical Entity (NCE) exclusivity to lisdexamfetamine dimesylate - currently marketed by the US unit of UK-based drugmaker Shire for the treatment of attention-deficit hyperactivity disorder under the name Vyvanse. The five-year exclusivity period expires on February 23, 2012. Vyvanse is covered by US patents which remain in effect until June 29, 2023, the UK firm notes.

On February 23, 2007, after reviewing the requisite clinical studies submitted on behalf of VYVANSE, the FDA determined that Vyvanse qualified as a NCE and was entitled to five-year market exclusivity. The agency therefore appropriately refused to file the Abbreviated New Drug Application submitted by Actavis Elizabeth for generic lisdexamfetamine dimesylate in January 2009. On February 24, 2009, Actavis sued the FDA in the District Court of the District of Columbia challenging the NCE decision. On April 13, 2009, the FDA opened a public docket to consider Actavis' challenge to the FDA's regulations governing NCE exclusivity and the corresponding award of exclusivity to Vyvanse. The court case was stayed pending the outcome of this FDA review.

More than a year ago, a new Pharmacor report, titled Attention-Deficit/Hyperactivity found that Vyvanse will garner $1.2 billion in sales in 2017, owing in large part to the drug's robust efficacy, its approval for both children and adults, as well as its lower abuse potential compared with other first-line psychostimulants.

Subsequently, Shire struck a deal with UK drugs giant GlaxoSmithKline to co-promote Vyvanse in the USA, sending the former's shares sharply higher, fueled by speculation that the move was a prelude to a takeover by GSK (The Pharma Letter April 1).

Industry analysts said the addition of GSK's marketing muscle could add some $500 million to Vyvanse's sales potential, and Jeremy Batstone-Carr of Charles Stanley speculated that GSK might go on to launch a bid for Shire in due course.