Shire plc expects strong growth in sales of Vyvanse to offset any loss in market share experienced by its best selling, once-daily treatment for attention deficit/hyperactivity disorder (ADHD), Adderall XR, due to generic competition. Aiming to improve the recognition and treatment of ADHD in kid and adult populations-- and boost its own sales -- the drug maker has unveiled a new ADHD-related support resource available through the online networking medium Twitter.
The importance of Adderrall to Shire is in the numbers, with sales of $1.1 billion in 2008. For the third-quarter ending September, product sales of Adderrall XR (mixed salts of a single-entity amphetamine) fell 74 percent to $70.9 million, crippled by the authorized U.S. launch of a generic version by Teva Pharmaceuticals in April 2009. Higher managed care and Medicaid rebates subsequent to Teva's rollout adversely impacted branded product sales too.
The company has been unable to capitalize on its historically dominant position in the ADHD realm (33 percent of the branded U.S. marketing pie in 2008) and a three-year co-promotion agreement signed with GlaxoSmithKline (started in May 2009): Vyvanse (lisdexamfetamine dimesylate) sales totaled just $129 million in the third-quarter ending September 2009. On a more positive note, the drug's share of the branded market did jump 400 basis points to 13 percent, according to Shire's third-quarter 2009 regulatory filing.
It is questionable whether Shire can match past successes of its Adderrall portfolio, as cheap copycats continue to flood the behavior-disorder sphere. For example, the company has been unable to gain much traction for Daytrana, its transdermal patch of the common psycho-stimulant compound methylphenidate, popular in controlled-release formulations like Concerta XL (Johnson & Johnson) and Ritalin SR (from Novartis). Third-quarter 2009 sales registered just $17.4 million, with year-on-year prescription demand declining 12 percent in the U.S.
Popular competitors losing market exclusivity could further restrict future uptake of Vyvanse with physicians: Indian generic firm Aurobindo Pharma received tentative first-to-launch approval from the FDA for atomexetine -- Strattera (U.S. sales of $437.8 million in 2008 for Eli Lilly).
Shire's executive vice president Mike Cola told analysts on the third-quarter 2009 earnings call that there was still growth to be had in the ADHD market, with the adult segment growing four times to five times the pediatric rate. Total weekly prescriptions topped 900,000 in October, up some 20 percent from the total weekly average in the prior three years, according to industry data. Whether or not the effect of this innovative and new direct-to-consumer approach yields product specific -- or class-wide -- benefits, however, remains to be tweeted.