Early Treatment With Alglucosidase Alfa Prolongs Long-Term Survival of Infants With Pompe Disease

In a previous 52-wk trial, treatment with alglucosidase alfa markedly improved cardiomyopathy, ventilatory function, and overall survival among 18 children <7 mo old with infantile-onset Pompe disease. Sixteen of the 18 patients enrolled in an extension study, where they continued to receive alglucosidase alfa at either 20 mg/kg biweekly (n = 8) or 40 mg/kg biweekly (n = 8), for up to a total of 3 y. These children continued to exhibit the benefits of alglucosidase alfa at the age of 36 mo. Cox regression analyses showed that over the entire study period, alglucosidase alfa treatment reduced the risk of death by 95%, reduced the risk of invasive ventilation or death by 91%, and reduced the risk of any type of ventilation or death by 87%, compared with an untreated historical control group. Cardiomyopathy continued to improve and 11 patients learned and sustained substantial motor skills. No significant differences in either safety or efficacy parameters were observed between the 20 and 40 mg/kg biweekly doses. Overall, long-term alglucosidase alfa treatment markedly extended survival as well as ventilation-free survival and improved cardiomyopathy.