Glaxo blockbuster Advair faces US copycats after FDA greenlight

10th Sep 2013 11:54

A report from the US drugs regulator has threatened to open up competition for GlaxoSmithKline's best-selling drug.Shares in the pharmaceuticals giant fell more than 3% after a report from the US Food and Drug Administration (FDA) suggested generic drugs identical to GSK's blockbuster asthma drug Advair could be developed more quickly and easily for the US market. Advair, which is known as Seretide outside the US and is also used to treat chronic pulmonary disease, has passed the end of its patent but was the company's best-selling product last year, generating sales of £5.1bn. In the first half of the current year, sales grew 5% to £2.7m, half of which in the US, and analysts at Credit Suisse said Advair accounts for about 20% of GSK's sales and more than 30% of profit. On Monday the FDA quashed the company's and its investors' hopes that fully substitutable generic copies of the inhaled drug would not be allowed, instead saying these would only require relatively rudimentary preclinical tests and a short clinical trial.This means other drug makers could have copycat versions using the same active ingredients but different delivery methods on the market in the next couple of years. Sandoz, the generics arm of Novartis, for example, had a generic version well advanced in development but handed the rights back to partner Vectura, which may find some interested parties in light of the news from the FDA.By 12:38, shares in GSK had recovered slightly to 1,592.5p, a fall of 2.9% on the day. OH