It’s impossible to put a price on a child’s life. But if your child suffers from a rare blood disorder called atypical hemolytic-uremic syndrome, you can expect to shell out more than $400,000 per year because that’s the price of the antibody drug that just received regulatory approval in the US to treat the clotting disease.

Atypical hemolytic-uremic syndrome (aHUS) is a life-threatening genetic disease affecting fewer than 1,000 Americans in which red blood cells break apart as they squeeze through small blood vessels leading to anemia, abnormal bleeding and kidney failure. Plasma exchange has become the standard of care for more than 30 years, but many people with aHUS do not tolerate or respond to the therapy. And even when it works, the procedure is time-consuming and not totally risk-free. So doctors have long sought treatments that actually target the root of the disease — the excessive activation of the complement system used by the immune system to clear pathogens from the body.

In 2009, two single-patient case reports came out showing that Alexion’s Soliris (eculizumab) helped an 18-month-old boy and a 30-year-old woman stabilize their disease. (The monoclonal antibody, which is directed against the complement protein C5, had been on the market since 2007 for the treatment of another rare blood disorder called paroxysmal nocturnal hemoglobinuria.) Alexion then launched two prospective open-label trials and a third retrospective study in a total of 56 people with aHUS. Reporting this summer at the European Hematology Association annual meeting in London, the company showed that the vast majority of those study subjects had no blood clots, improved kidney function and a better quality of life.

Last week, off the back of those results, the US Food and Drug Administration approved Soliris for all age groups with aHUS. Alexion also announced that the European Medicine Agency’s Committee for Medicinal Products for Human Use had given the product a favorable review. A final decision from European regulators is expected within two months.



The drug doesn’t come cheap, though. Currently priced at $409,500 per year, Soliris is the world’s most expensive medication, according to Forbes. And even though the drug is approved for only two rare conditions, it has proven quite profitable: Soliris pulled in $541 million in 2010, and sales are reportedly up by close to 50% so far this year.

What’s more, Alexion seems poised to rapidly expand the number of diseases for which the drug can be used. Last month, the company announced phase 2 data showing the drug works in people with an ultra-rare form of a chronic autoimmune neuromuscular disease called generalized myasthenia gravis. And, as we reported earlier this year, in June Alexion also launched a clinical trial testing Soliris in people with the form of hemolytic-uremic syndrome induced by Escherichia coli poisoning, a complication that arose in many victims of this summer’s tainted sprout outbreak in Germany.

Soliris is clearing lifting the spirits of people with all these rare diseases who now have a therapeutic option — and it’s also doing wonders for Alexion’s stock price, which has tripled over the past two years.