New River Pharmaceuticals of the USA, which is shortly to be taken over by the UK’s Shire, has reported a significant widening of losses for 2006.

Losses climbed almost 92% to $57.4 million, or $1.60 per share, for 2006, due principally to general and administrative expenses soaring over 270% to $49.0 million reflecting shared marketing expenses with Shire relating to Vyvanse (lisdexamfetamine dimesylate), the firms’ new treatment for attention deficit hyperactivity disorder which was approved by the US Food and Drug Administration last month.

R&D costs were $41 million compared to $18.4 million for 2005, which was also a result of increases in external development costs associated with Vyvanse, including manufacturing costs of validation batches and stock-based compensation expense. New River recognised $34.3 million of revenue from Shire with respect to the new ADHD drug.

The company noted that Shire’s tender offer commenced on March 2, and is expected to close early in the second quarter.