375 to 600 US late-onset Pompe patients are failing next-gen ERT, and ADA superiority decides who can reach them.

Nexviazyme (avalglucosidase alfa, Sanofi, approved 2021) is the growing leader in newly diagnosed late-onset Pompe disease, capturing an estimated 35-40% of new starts on the strength of its COMET trial result, a 23.5-metre six-minute-walk-test advantage over first-generation alglucosidase alfa. Pombiliti+Opfolda (cipaglucosidase alfa plus the miglustat chaperone, Amicus Therapeutics, approved 2023) entered the market with a switch-population claim from PROPEL, a 20.8-metre 6MWT gain in ERT-experienced patients, but on a different evidence base than Nexviazyme's, so prescribers are choosing on indirect evidence and individual anti-drug-antibody risk. WAC for both next-gen ERTs runs $600,000-800,000 a year, roughly 50-60% above first-generation alglucosidase alfa.

The clinical fact both incumbents have to answer for is ADA: 30-40% of Pompe ERT patients develop high-titre neutralising anti-drug antibodies that measurably reduce enzyme efficacy, the single question US Pompe KOLs ask first about any new agent. An estimated 25-30% of the roughly 2,000 US LOPD patients on ERT, 375-600 patients, are inadequate responders, most often driven by that high-titre ADA. This inadequate-responder cohort is the only clean pre-launch opening in a market already served by two next-generation ERTs; a third agent competing broadly, without an ADA advantage, has no differentiated claim to make.

A third agent without an ADA advantage has no differentiated claim to make.

Five questions this report answers:

Q1 - What ADA and functional-endpoint data must differentiate a new LOPD agent from incumbents?

Q2 - How large is the inadequate-ERT-responder cohort, and how is it identified pre-approval?

Q3 - What payer step-edit and Part B billing groundwork does a new LOPD agent need?

Q4 - What deliverable formats come with a commissioned US Pompe launch readiness assessment?

Q5 - What must a new Pompe LOPD ERT prove and prepare before a US launch?

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Live report page:  https://axlrx.ai/pompe-disease/launch-readiness/

Thanks & Regards,

Mike || Global Pharma Commercial Marketing Head

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Web-     https://axlrx.ai/