Pfizer won approval yesterday for a drug to treat a hospital-acquired fungal infection that kills up to 40% of the patients who contract it.

The US Food and Drug Administration (FDA) cleared the new intravenous product, called Eraxis (anidulafungin), to treat candidaemia, which affects around 60,000 people in the USA every year. The agency also cleared the drug for other infections caused by the yeast Candida, including invasive oesophageal candidiasis, abdominal abcesses and peritonitis.

Along with Vfend (voriconazole), introduced in 2002, Eraxis will help Pfizer inject some new vigour into its antifungal franchise, which was hit by the patent expiry on its big-selling Diflucan (fluconazole) product in 2004. Sales of Diflucan fell by nearly 50% last year to just under $500 million. The new agent has been shown to be superior to Diflucan in clinical trials.

"Bloodstream infections such as candidaemia can spread quickly and are very dangerous, especially for patients with weakened immune systems," said Joseph Feczko, Pfizer's chief medical officer. "Physicians treating these seriously ill patients now have an important new treatment in Eraxis."

US patients with candidaemia generally spend around 10 extra days in hospital, resulting in additional hospital charges averaging $39,000 per patient.

Eraxis is one of two anti-infective agents acquired by Pfizer when it bought Vicuron Pharmaceuticals last year for $1.9 billion. The other is dalbavancin, an antibiotic for skin and soft tissue infections that is viewed as a potential successor to Zithromax (azithromycin), another blockbuster medication that saw the start of generic competition last November.

Dalbavancin is currently under review at the FDA and is expected to be approved later this quarter.