Shire, New River receive approvable letter for ADHD compound

Shire Friday received tentative FDA approval to market its new attention-deficit hyperactivity disorder (ADHD) drug, lisdexamfetamine dimesylate (LDX). The compound was created and tested by New River Pharmaceuticals, which will co-market the drug with Shire. LDX is expected to follow in the footsteps of Shire’s ADHD market-leading drug Adderall XR but is formulated to be harder to abuse. LDX currently has no brand name because the FDA has rejected marketer’s proposals as too similar to other drugs. The compound has also been referred to by the FDA number NRP104. Formal LDX approval still hinges on review by the US Drug Enforcement Administration, which regulates most ADHD medications because they are stimulants. Shire said in published reports that it anticipates launch of LDX sometime in the first half of 2007. News of the FDA’s approvable letter regarding LDX sent shares in both companies soaring to record highs. Shire stock rose 15 percent in London, the biggest jump since April 2000. New River’s gain was the biggest since the company began selling shares to the public in August 2004. US approval would make LDX New River's first product on the market. Adderall XR brought in nearly $975 million in sales for Shire in 2005, followed by McNeil Consumer and Specialty Pharmaceuticals’ Concerta, with sales of $838 million and Eli Lilly’s Strattera with sales of $662 million.