Press Release: Sanofi’s Nexviazyme met all primary and secondary endpoints in infantile-onset Pompe disease phase 3 study

Sanofi said Nexviazyme (avalglucosidase alfa) met the primary endpoint in its Baby-COMET Phase 3 trial for infantile-onset Pompe disease, with treatment-naïve infants 0-6 months alive and free of invasive ventilation at 52 weeks (primary endpoint) and all secondary endpoints also met. Safety was consistent with the established profile, with manageable infusion-associated reactions reported in 29.4% of participants and no serious treatment-related TEAEs, deaths, or discontinuations. Sanofi plans to submit data to the US FDA to support a regulatory application for this label extension in 2H 2026.

Analysis

This is positive for SNY, but the economic delta is likely modest versus the strategic value. The meaningful mechanism is not near-term sales from infant Pompe; it is label credibility: a clean pediatric dataset lowers perceived regulatory risk around Sanofi’s entire ERT franchise and should modestly support physician and payer confidence in pricing power across the Pompe continuum.

Second-order, the result hardens Sanofi’s moat against future rare-disease entrants because early-life ventilator-free survival is a difficult endpoint for challengers to replicate. That said, the study design is open-label and single-arm with only 17 patients, so the market should not extrapolate this into broad revenue upside without seeing FDA filing acceptance, label scope, and reimbursement language; the biggest risk is a narrow indication that limits commercial impact.

Contrarian view: consensus will likely treat this as a clean positive and move on, but the real question is whether it changes long-duration valuation. If management can pair this with stronger Pompe franchise economics or adjacent lysosomal pipeline read-through, it supports a small multiple lift; otherwise the stock reaction may fade once investors realize this is more pipeline de-risking than EPS accretion. Falsifier: FDA delay, label restriction, or any signal that the agency wants randomized confirmatory evidence before broadening the US indication.

Key Decisions for Investors

• Do not chase an opening gap higher in SNY; if the stock rallies >2-3% on the print, fade part of the move because the fundamental earnings impact is likely de minimis.
• Build a modest 3-6 month long SNY position on any post-news pullback, targeting the H2 2026 US filing catalyst; thesis breaks if FDA narrows the label or pushes for additional trial work.
• Relative-value idea: long SNY vs a basket of large-cap pharma with weaker rare-disease optionality (e.g., BMY/NVS) on the view that this improves pipeline credibility more than peers' near-term fundamentals.
• Set an alert for the July 8 data presentation and subsequent FDA interaction; if management commentary suggests a restricted label or delayed submission, reduce or exit the long.