Alexion Pharmaceuticals announced that researchers have presented data from an ongoing multinational Phase 2 study of asfotase alfa in infants and young children with hypophosphatasia, HPP, an inherited, ultra-rare metabolic disorder that in this patient population leads to progressive damage to multiple vital organs, destruction and deformity of bones, and death. The study met its primary endpoint: infants and young children with HPP treated with asfotase alfa had significant improvement in skeletal mineralization from baseline as assessed radiographically after 24 weeks of treatment (p=0.001). This response was observed as early as 12 weeks and improvement continued at 48 weeks. Ninety three percent of the patients survived the first 48 weeks of treatment with 80% of patients having improved respiratory status or requiring no respiratory support at the final analysis. The data were presented in a late-breaking presentation at the 9th Joint Meeting of Paediatric Endocrinology in Milan, Italy.