The USA’s Alexion Pharmaceuticals is celebrating after receiving its first-ever approval from the country’s regulators which could see the blood disorder drug Soliris hit the market by the end of the month.

The US Food and Drug Administration has approved Soliris (eculizumab) for paroxysmal nocturnal hemoglobinuria, a rare, disabling and life-threatening blood disorder defined by chronic red blood cell destruction, or haemolysis. Alexion noted that PNH “often strikes people in the prime of their lives,” with an average age of onset in the early 30s and the estimated median survival is between 10 and 15 years from the time of diagnosis.

Patients with PNH are missing a specific protein that normally protects red blood cells from destruction by a component of the immune system called terminal complement and Soliris is the first complement inhibitor approved in the USA. 8,000 to 10,000 people in North America and Europe are affected by the disorder, the company added.

The approval, which sent Alexion shares up more than 7% to $40.15, was based on three multi-national clinical studies: Triumph, a placebo-controlled 26-week Phase III study involving 87 PNH patients, Shepherd, an open-label year-long, late-stage trial involving 97 patients and E05-001, a long-term extension study. All of them showed that Soliris reduced haemolysis in every treated patient. Alexion added that the drug is currently under review with regulators in Europe.

The market may be small but it should be a very lucrative one for Soliris, and although Alexion has not given any information on pricing yet, estimates range from $100,000 per patient per year, to as much as $300,000, which may cause some controversy given the debate on reducing healthcare costs in the USA and indeed across the globe.

Nevertheless, this could mean that Soliris brings in $500 million a year for Alexion which recently reported revenues of $200,000 and a net loss of $39.3 million for the fourth quarter of 2006. The company added that it has established a programme to ensure that all patients who need eculizumab have access to the drug and noted that Soliris will carry a boxed warning saying that it can increase susceptibility to meningococcal infections so patients must be vaccinated at least two weeks before starting treatment.