The Food and Drug Administration has delayed a bid by
to expand its empire of drugs that treat attention deficit hyperactivity disorder.
With two ADHD drugs on the market and another due to be launched next month, Shire says a fourth compound has received conditional approval from the FDA. Shire's announcement on Saturday didn't reveal the conditions, or timetable, for FDA approval. The British drugmaker only said it was evaluating its options.
The experimental drug, called SPD465, is a chemical relative of Adderall XR, which is Shire's best-seller. Although Adderall XR lasts for 12 hours, SPD465 is good for 16 hours. Adderall XR is approved for children, adolescents and adults. Shire asked the FDA to approve SPD465 for adults.
On Monday, Shire's stock was up 3 cents to $69.80. Under most circumstances, an FDA delay would be viewed by investors as a setback. But Shire executives told investors in late April that even if the FDA approved SPD465, the company probably wouldn't market it this year.
Shire is devoting its marketing money and staff to
launching Vyvanse, an ADHD drug approved by the agency in February for children ages 6 to 12. Shire also plans to seek FDA approval for Vyvanse in adults.
Executives predict Vyvanse will eventually outsell Adderall XR.
Shire also sells the ADHD drug Daytrana, which is administered via a skin patch and is approved for children 6 to 12. Next month, Shire expects to hear from the FDA on a nonstimulant ADHD drug called SPD503. It's an extended-release version of a generic blood-pressure drug, and it's designed for children ages 6 to 17.