IPM Take
In infantile-onset Pompe disease, delay is not a neutral administrative outcome. It is a clinical event.
That is why Baby-COMET matters. Survival without invasive ventilation is not a convenient endpoint. It is about whether a baby stays alive without a machine taking over the work of breathing.
But urgency does not remove the need for scrutiny. A rare-disease trial can be small because the population is small. It cannot be treated as beyond the normal demands of honest evidence because the disease is devastating.
Executive Summary
Sanofi reported that Baby-COMET, a Phase 3, single-arm, open-label study of avalglucosidase alfa in infantile-onset Pompe disease, met its primary endpoint: the proportion of treatment-naive infants aged six months or younger who were alive and free of invasive ventilation after 52 weeks of treatment.
The international study enrolled 17 infants aged 12 months or younger, all treated with intravenous avalglucosidase alfa at 40 mg/kg every other week. Sanofi also reported that all secondary endpoints were met, including ventilator-free survival at 12 and 18 months of age and numerical improvements in disease-progression measures at week 52.
The findings are company-reported and have not yet been published in a peer-reviewed journal. There was no concurrent comparator group. Full data are due to be presented on 8 July at the International Congress on Neuromuscular Diseases in Florence. Sanofi says it plans a US label-extension submission in the second half of 2026.
Why it matters
- Patients / advocates: In a disease that can progress rapidly in the first months of life, ventilator-free survival is a real-life outcome, not an abstract trial statistic.
- Clinicians: The result is clinically important, but the small, non-randomised design means comparative effectiveness, durability and functional outcomes still need close examination.
- Regulators: Rare paediatric disease needs flexibility. It does not need a lower bar for explaining what the evidence can and cannot prove.
Infantile-onset Pompe disease does not leave a system time to be leisurely.
Without treatment, the condition can rapidly damage the heart, breathing muscles and movement, with life-threatening consequences in the first year of life. That is why trials in this space cannot be judged as though they were recruiting from an abundant adult population with years to spare.
Baby-COMET has now delivered a meaningful signal. Sanofi says the study met its primary endpoint of invasive ventilator-free survival at 52 weeks in the prespecified younger treatment-naive group, with all secondary endpoints also met. The company reported no treatment-related serious adverse events, deaths or discontinuations, while infusion-associated reactions were described as manageable.
That is encouraging. It is not the end of the argument.
The study was single-arm and open-label. There was no concurrent comparator. Rare-disease development often creates a political temptation: to treat the absence of a feasible randomised trial as permission to stop asking hard questions about effect size, long-term safety, functional benefit and comparative value.
It should mean the opposite.
When randomisation is difficult, the job becomes to build stronger external comparisons, transparent natural-history frameworks and follow-up that does not disappear once the regulatory decision is secured. Families facing an infantile disease deserve speed. They also deserve a system that can explain, clearly and without sales language, what a treatment has shown and what it still has to prove.
