Roche has announced that it will not be introducing the 625mg formulation of the protease inhibitor nelfinavir (Viracept) in Europe because of production problems. The 625mg formulation has been available to patients in the UK since early 2004 under a special licensing scheme, and these individuals will now be switched to an alternative drug, an option being the 250mg formulation of nelfinavir which has not been affected by production difficulties.
A spokesperson for Roche told aidsmap.com that insurmountable problems had been encountered with the film coating of the 625mg nelfinavir tablets. These were not affecting the potency or efficacy of the drug, however they were resulting in the tablets crumbling. The problem became apparent in the summer and from August the 625mg formulation of nelfinavir ceased to be available to new patients under the special licensing scheme.
Approximately 500 patients in the UK are taking the 625mg formulation of nelfinavir and will now have to switch to an alternative drug. The 625mg pill substantially reduced the nelfinavir pill burden from five pills twice daily on the 250mg formulation to just two pills twice a day. It is questionable how attractive many patients with treatment options other than nelfinavir open to them will find the prospect of returning to a regimen with such a high pill burden.
Patients currently taking nelfinavir 625mg pills should be told at their next clinic appointment that the drug is no longer available and should be offered an alternative treatment. All patients should have stopped taking nelfinavir 625mg by the end of May 2005, Roche said.
In the United States the 625mg formulation will continue to be manufactured and marketed by Pfizer, which owns the marketing rights in North America and the Caribbean. Pfizer's 625mg tablet is a different formulation from the Roche product, and bioequivalence data are not available. As a result Roche cannot simply buy US stock and import it to Europe for patients already taking the 625mg tablet, but would need to carry out new studies and obtain approval for the product in Europe.