Inclusion Criteria:  Assent from the pediatric subject, as appropriate, and fully informed consent from the parent(s) or legal guardian, as required by both state and federal laws and the local Institutional Review Board (IRB); Subjects ≥4 and <18 years of age; Clinical diagnosis of type 1 diabetes mellitus (T1DM) or type 2 diabetes mellitus (T2DM) per the Investigator and have been using insulin for at least 6 months for T1DM, or at least 3 months for T2DM Treatment with basal-bolus insulin therapy delivered by multiple daily injections for at least 2 weeks: Acceptable bolus insulins are restricted to the RAAs insulin lispro or insulin aspart, including biosimilar products. Basal insulins are restricted to 100-U/mL formulations of insulin glargine or insulin degludec, including biosimilar products. Access to stable WiFi connection HbA1c ≥7.0% and ≤11% Average prandial dose of insulin ≥2 units per meal Utilized continuous glucose monitor (CGM) for ≥70% of the time over a 14-day period preceding randomization.  Exclusion Criteria:  History of recent blood transfusions (within previous 3 months), hemoglobinopathies, or any other conditions that affect HbA1c measurements History of asthma, any other clinically important pulmonary disease (e.g., cystic fibrosis or bronchopulmonary dysplasia), use of any medications to treat such conditions within the last year, or significant congenital or acquired cardiopulmonary disease History of serious complications of diabetes (e.g., active proliferative retinopathy or symptomatic autonomic neuropathy), or likely need for specific treatment for diabetic retinopathy (laser photocoagulation, vitrectomy, other) in the next year. FEV1 and FEV1/forced vital capacity (FVC) ≤80% of predicted Global Lung Function Initiative (GLI) value Inability to achieve an acceptable FEV1 and FVC reading for subjects ≥8 years of age would make the subject ineligible For subjects <8 years of age who are unable to achieve an acceptable FVC reading, FEV1 only may be assessed; inability to achieve an acceptable FEV1 would make the subject ineligible Respiratory tract infection within 14 days before screening or between the screening and randomization visits (subject may return 14 days after resolution of symptoms for rescreening) Inability or unwillingness to perform study procedures Exposure to any investigational product(s), including drugs or devices, in the past 30 days Any disease other than diabetes or exposure to any medication that, in the judgment of the Investigator, may impact glucose metabolism, including liraglutide, and current or anticipated acute uses of glucocorticoids or weight loss medications, with the exception of metformin in subjects with T2DM Use of antiadrenergic drugs (e.g., clonidine) Any concurrent illness (other than diabetes mellitus) not controlled by a stable therapeutic regimen History of a significant eating disorder (e.g., anorexia or bulimia nervosa) Current drug or alcohol abuse or a history of drug or alcohol abuse that, in the opinion of the Investigator or the Sponsor, would make the subject an unsuitable candidate for participation in the study Smoking (includes cigarettes, cigars, pipes, marijuana, and vaping devices) for the preceding 6 months and/or positive urine cotinine test Female subject who is pregnant, breast-feeding, intends to become pregnant, or is of child-bearing potential, sexually active and not using adequate contraceptive methods as required by local regulation or practice An event of severe hypoglycemia, as judged by the Investigator, within the last 90 days prior to screening An episode of diabetic ketoacidosis (DKA) requiring hospitalization within the last 90 days prior to screening