Study to Compare the Efficacy and Safety of Enzyme Replacement Therapies Avalglucosidase Alfa and Alglucosidase Alfa Administered Every Other Week in Patients With Late-onset Pompe Disease Who Have Not Been Previously Treated for Pompe Disease

Inclusion criteria : * The participant has confirmed acid alpha-glucosidase (GAA) enzyme deficiency from any tissue source and/or 2 confirmed GAA gene mutations. * The participant must provide signed, informed consent prior to performing any study related procedures. Consent of a legally authorized guardian(s) is (are) required for legally minor participant as defined by local regulation. If the participant is legally minor, signed written consent shall be obtained from parent(s)/legal guardian and assent obtained from participants, if applicable. Exclusion criteria: * The participant is \<3 years of age. * The participant has known Pompe specific cardiac hypertrophy. * The participant is wheelchair dependent. * The participant is not able to ambulate 40 meters (approximately 130 feet) without stopping and without an assistive device. * The participant requires invasive-ventilation (non-invasive ventilation is allowed). * The participant is not able to successfully perform repeated forced vital capacity (FVC) measurements in upright position of greater than or equal to 30% predicted and less than or equal to 85% predicted. * The participant (and participant's legal guardian if participant is legally minor as defined by local regulation) is (are) not able to comply with the clinical protocol. * The participant has had previous treatment with alglucosidase alfa or any investigational therapy for Pompe disease. * The participant has prior or current use of immune tolerance in…