Despite success in other parts of the world, Opko Health Inc. and Pfizer Inc. are still struggling to gain U.S. FDA approval for the recombinant human growth hormone somatrogon in treating pediatric patients, drawing a complete response letter (CRL) with their BLA. The delay caused by the setback gives Skytrofa (lonapegsomatropin) from Ascendis Pharma A/S a chance to charge even further ahead in the pediatric market.