UK-headquartered pharma giant GlaxoSmithKline says it has overcome the manufacturing problems that caused it to voluntarily withdraw its antidepressant Paxil CR (paroxetine) and diabetes drug Avandamet (metformin and rosiglitazone) from the US market earlier this year.
GSK has already started shipping Paxil CR tablets to pharmacies across the US, with other markets to follow shortly.
In March, the US Food and Drug Administration (FDA) seized shipments of both Paxil and Avandamet from distribution and manufacturing facilities operated by GSK in Cidra, Puerto Rico, and Knoxville, US.
The agency had found that Paxil CR tablets could be split apart, potentially leading to the absence of the active ingredient or controlled-release factor, while some Avandamet tables had the incorrect dose of one active ingredient.
As a result, GSK had to sign a consent decree with the FDA in May, leaving it open to fines in addition to the estimated $300m lost in interrupted sales. It seems now no financial penalties will be forthcoming.
GSK says it has now implemented revisions to the source of the production problem the nature of which, it says, did not relate to any significant safety issues. These revisions have been certified by a Quantic, a company authorised by the FDA to carry out validation work, according to the group. It also expects that distribution channels will re-open for Avandamet within two weeks.
The news is also a welcome boost for UK drug delivery company SkyePharma, whose technology underlies the Paxil CR product.
In a statement, SkyePharma's CEO, Michael Ashton said: "Paxil CR was designed to address the side-effect of early nausea that affects many patients being treated with SSRI antidepressants so its return to the US market fills an obvious therapeutic gap."
He also noted that the product was SkyePharma's most important source of royalty income in 2004.
"We are confident that a rebuild in US revenues, and the new higher royalty rate, will mean that it will also be the major source of royalty income in 2005," said Ashton.