Alexion wins a pair of EU approvals to build out its rare disease ranks

Alexion Pharmaceuticals ($ALXN) is no longer a one-product company, winning tandem European approvals for two rare disease drugs it hopes will mimic the success of Soliris, the world's most expensive treatment.

The European Commission signed off on asfotase alfa, a treatment for the ultrarare pediatric-onset hypophosphatasia (HPP), and sebelipase alfa, which targets the similarly uncommon lysosomal acid lipase deficiency (LAL-D). The former, invented by Alexion, will sell as Strensiq; and the second, brought in through the company's $8.4 billion acquisition of Synageva this year, is dubbed Kanuma. Ultrarare diseases are those that affect fewer than 20 for every 1 million people.

Now begins the process of discussing pricing with the EU's 28 member states, a contentious topic for global regulators when it comes to companies like Alexion. Soliris, approved for a pair of rare diseases, goes for more than $500,000 a year, and while Alexion has largely been successful in convincing governments and payers to shell out for the therapy thanks to its excellent record of efficacy, it has repeatedly had to defend its drug's worth.

The company hasn't disclosed price tags for Strensiq and Kanuma, but Barclays analyst Geoff Meacham wrote in a note to investors that Alexion will likely charge about $375,000 a year for each. Meacham figures the two drugs could bring in a combined $2 billion a year at their peak.

HPP is a metabolic disease characterized by defective bone formation, leading to deformities and respiratory issues that often prove fatal, and Strensiq is designed to replace the deficient enzyme responsible. LAL-D is caused by a genetic mutation that results in a loss of LAL enzymes, contributing to dangerous buildups of cholesterol and triglycerides that can severely damage the liver. Kanuma, also an enzyme-replacement therapy, works by counteracting that process.

In the U.S., each drug has received the FDA's coveted breakthrough-therapy designation, given to promising treatments for diseases with high unmet need. The award promises Alexion access to top regulators throughout the process and presents a chance for speedy approval, and the company is awaiting final word on both treatments.

- read the Strensiq statement
- here's the Kanuma release