Survival and developmental milestones among Pompe registry patients with classic infantile-onset Pompe disease with different timing of initiation of treatment with enzyme replacement therapy (ERT)

s S62 strength in the arms (pulls self to stand: 72% vs 47%) and legs (bears weight on legs: 79% vs 66%). Results were similar when patients from Taiwan, who may have been identifi ed by newborn screening and not clinical diagnosis, were excluded. Earlier initiation of ERT in classic IOPD patients appears to improve the chances of survival and leads to better retention of muscle strength and improvement of symptoms in these young patients affected most severely by Pompe disease.