- Shire's neuroscience portfolio got a boost on Tuesday after the Food and Drug Administration approved the company's investigational drug for a common condition that impairs focus.
- Mydayis, a mixture of amphetamine salts formerly known as SHP465, got a thumbs up from the agency as a treatment for attention deficit hyperactivity disorder (ADHD) for those aged 13 and older. Shire plans to start commercializing the drug in the third quarter, according to a June 20 statement.
- While the vast majority of adult ADHD patients don't receive proper diagnosis or treatment, the Anxiety and Depression Association of America estimates there at least 8 million adults in the U.S. with the disorder. That population may find Mydayis preferential to other treatments, such as Shire's extended release (XR) Adderall, because of its longer, 16-hour duration, according to investment firm Jefferies.
Shire is the dominant player in ADHD, with Adderall XR, Intuniv (guanfacine) and the highly lucrative Vyvanse (lisdexamfetamine dimesylate) at its disposal.
As is common among branded drugmakers, however, generic competition has taken a toll on the Irish pharma's revenues. Copycat versions of Adderall XR and Intuniv, for example, have been on the market since 2009 and 2014, respectively, and contributed to steep declines in sales for both products.
Mydalis is likely to make up for some of those declines. Clinical data showed the drug works for up to 16 hours, much longer than Adderall XR, another mixture of amphetamine compounds. Consensus among analysts is that the new medication will hit $288 million in sales by 2020, according to Jefferies. But those projections may be too conservative. Shire, conversely, expects its drug to reach $500 million in sales by that year.
"Given Shire's expertise in the area, we are inclined to agree with management, and note that every ADHD drug Shire launched has outperformed," Jefferies analyst Peter Welford wrote in a June 20 note, adding his company anticipates $425 million in peak Mydayis sales.
Mydayis would also shoulder some of the weight that Vyvanse has been carrying for Shire's neuroscience business. The latter drug raked in $563.7 million worth of sales during the first quarter alone, an 11% jump from the same period in 2015 that stemmed from a few factors, including more prescriptions and a price hike. Additionally, Vyvanse benefited from a label expansion in early 2015, indicating it for the treatment of binge-eating disorder.
The blockbuster drug has faced its own share of patent battles, though. In 2015, Shire won out in court against a handful of other pharmaceutical developers looking to market their own versions of the product. Vyvanse was first approved in 2007 and loses exclusivity in 2023, though Shire could extend exclusivity by proving the treatment's effectiveness and safety in preschool-age children.
The combination of Mydayis and Vyvanse should allow Shire to keep its strong position in the growing ADHD field. Other big pharmas such as Johnson & Johnson and Novartis have attention-improving drugs on the market, and smaller players like NLS Pharma are creeping closer to market with new pipeline candidates as well.
Shire stock was up 1.6% to $169.96 per share in Wednesday afternoon trading. Supernus Pharmaceuticals, which co-developed Mydayis, also saw shares rise 2.7% to $42.50 apiece.