GSK Wellbutrin XL joins IR and SR formulations
This article was originally published in Pharmaceutical Approvals Monthly
Executive Summary
FDA approves GlaxoSmithKline's latest bupropion formulation, Wellbutrin XL, for treatment of major depressive disorder Aug. 28, shortly ahead of the agent's Sept. 3 user fee goal. The firm plans a mid-September launch of the extended-release norepinephrine/dopamine reuptake inhibitor; GSK licensed the once-daily formulation from Biovail. Timing of the approval provides GSK with a short time to try and convert patients from its twice-daily product, Wellbutrin SR, to XL before the SR product faces generic competition. Andrx indicated its intent to launch generic SR within the first few months of XL's launch. The generic firm is hoping that uptake of XL will be hindered by the absence of a comparison to SR in labeling; approved labeling only notes similar bioavailability of XL (300 mg once a day) to immediate release Wellbutrin (100 mg three times a day). GSK will likely position XL as offering an improved safety profile, with reduced seizures and sleeplessness...