The phenotype of spinal muscular atrophy (SMA) has been changing with the recent 
availability of three FDA-approved treatments: intrathecal nusinersen, 
intravenous onasemnogene abeparvovec-xioi, and enteral risdiplam. The degree of 
improvement in muscle strength and respiratory health varies with SMA genotype, 
severity of baseline neuromuscular and pulmonary impairment, medication used, 
and timing of the first dose. A spectrum of pulmonary outcomes has been reported 
with these novel medications when used early and in conjunction with proactive 
multidisciplinary management of comorbidities. In this review, we summarize the 
reported impact of these novel therapies on pulmonary well-being and the 
improving trajectory of pulmonary morbidity, compared to the natural history of 
SMA. The importance of ongoing clinical monitoring albeit the improved phenotype 
is reiterated. We also discuss the limitations of the current SMA-therapy trials 
and offer suggestions for future clinical-outcome studies and long-term 
monitoring.