Controlled-release formulations show massive growth

The number of drugs being developed as controlled release formulations is growing rapidly, according to data published by Pharmaprojects, a leading database tracking pharmaceutical development from early preclinical study through to launch or discontinuation.

It is becoming generally acknowledged that controlled release formulations have the greatest revenue potential of any drugs enhanced by drug delivery technology.

In an increasingly competitive drug discovery market where regulatory bodies are becoming ever more stringent, controlled-release formulations represent one of the most important strategies for successful business, says Pharmaprojects, which has followed the development of controlled-release formulations for more than 20 years. Its data show that between 1995 and 2003 the number of controlled-release formulations rose dramatically from 223 to 397, with increases in the last three years being particularly sharp.

'Controlled-release drugs are attractive to pharmaceutical companies for several reasons,' says Pharmaprojects' managing editor Ian Lloyd. 'They have already been through the rigorous testing demanded by the regulatory authorities so withdrawal is highly unlikely. Further, the convenience that controlled-release formulations give improves patient compliance and therefore disease management.'

Notable success stories include J&J's Procardia XL, the controlled release version of nifedipine which generated an extra US$9bn worth of sales, and Cardizem CD, a once-daily formulation of diltiazem, which increased Elan's revenues for this drug to US$900m. This trend looks set to continue, according to Phar-maprojects, whose analysis reveals a further 20 controlled-release products currently awaiting approval.