British drug maker Shire PLC announced on Friday that its fourth-quarter net profit climbed year-on-year 23 per cent to $174.3 million, driven mainly by the strong sales of attention deficit and hyperactivity disorder treatment drug Vyvanse.

The British group expects revenue to grow again in 2010 as it has plans to launch six new drugs this year.

Revenues from Vyvanse alone jumped more than expected 41 per cent to $145 million during the final three months of last year.

Company’s CEO Angus Russell said, “New products have replaced the gap left by declining Adderall XR sales.”

Overall, sales during 2009 remained flat at $3 billion.

The company has bagged hundreds of new patients for its drugs velaglucerase and Replagal due to insufficient supply of Genzyme's costly drugs Cerezyme and Fabrazyme, which are used to cure Gaucher and Fabry disease respectively.

In the after-hours trading, shares in Shire gained 7.3 per cent to hit a 9-year high.