One company seeking to circumnavigate this problem is Cephalon, which sells a lozenge-on-a-stick formulation of an opioid analgesic, called Actiq (fentanyl), intended for on-demand relief of breakthrough pain in patients suffering from cancer. Each lozenge of Actiq contains 2 grammes of sugar.
The risk of tooth decay with Actiq is a well recognised phenomenon which eventually required a change to the product's labelling to highlight the risks. Actiq is particularly prone to the problem because, like all opioids, it inhibits the production of saliva, causing dry mouth which exacerbates the risk of decay. Saliva inhibition is often encountered, particularly in elderly people with numerous drugs prescribed on a long-term continuous basis, and in psychiatric patients. It remains a neglected clinical problem.
Cephalon has just received an approval letter from the US Food and Drug Administration (FDA) to market a new sugar-free formulation of Actiq which is bioequivalent to the currently available product, will be marketed for the same indication as ACTIQ using the same name.
"With this approval, we will move forward with our plans to launch the sugar-free formulation of Actiq in the first half of 2006," said Dr Paul Blake, executive vice president, worldwide medical & regulatory operations at the company.
Studies in healthy volunteers demonstrated bioequivalency between the sugar-free and the currently marketed formulation of the drug. Bioequivalent status means that a pharmacist can substitute one prescription for the other without a doctor's permission.
Aside from the benefits in preventing tooth decay, a sugar-free formulation also provides some brand protection for Actiq, which is due to lose patent protection in March 2007. The new formulation adds 20 years of exclusivity to the franchise and is expected to drive growth over the coming years.
Cephalon recently merged with drug delivery specialist CIMA Laboratories, which has been developing a fast-melt formulation of fentanyl for controlling cancer pain.