SPD465 equivalent to Adderall XR plus MAS-IR in adult ADHD

UK drugmaker Shire says that its drug SPD465 (triple-bead mixed amphetamine salts) has shown bioequivalence to Adderall XR (mixed amphetamine salts) plus a dose of immediate release mixed amphetamine salts, in reducing the symptoms of attention-deficit hyperactivity disorder in adult patients. SPD465, which is designed to treat the condition for up to 16 hours, was examined in a Phase I trial, results from which were presented at the US Psychiatric and Mental Health Congress in New Orleans, earlier this month.

The program enrolled 20 subjects who were randomized to receive either a once-daily 37.5mg administration of SPD465, or 25mg Adderall XR followed eight hours later by 12.5mg of MAS-IR. Participants initially underwent a seven-day washout period, before receiving either regimen for two and half days. Blood samples were collected from subjects during this phase of the program, with each treatment cohort being switched to receive the alternate therapy once the two and a half day period had elapsed.

The results showed that plasma concentrations of both D-amphetamine and L-amphetamine were similar in the two groups (50.3ng/ML for SPD465 and 49.3ng/ML for the Adderall /MAS-IR arm). The firm added that no clinically meaningful differences occurred between the groups in terms of adverse events, which were generally considered mild and were resolved prior to the program's conclusion, with the exception of one case of acne.