UK Pompe Disease Payer & HTA

NHS England's Pompe commissioning continuation criteria define a switch-eligible population of 45-50 inadequate responders — the manageable, evidence-backed target now addressed by avalglucosidase alfa's NICE TA821 recommendation.

Alglucosidase alfa (Lumizyme/Myozyme) has been commissioned by NHS England as a highly specialised service since 2014, under an NHS clinical commissioning policy rather than a formal NICE technology appraisal, with a confidential Patient Access Scheme bringing net cost to an estimated £200,000-£350,000 per patient per year for the roughly 180 UK patients currently on enzyme replacement therapy. The NHS commissioning policy's continuation criteria require FVC and 6-minute walk test (6MWT) reassessment at 12 and 24 months; therapy is discontinued if FVC declines by 20% or more alongside a 10% or greater 6MWT decline over 12 months, confirming clinical benefit is no longer demonstrated. UK Pompe Consortium outcomes registry data show approximately 25% of UK late-onset Pompe disease (LOPD) patients on alglucosidase experience FVC decline of 5-15% over five years, inadequate responders by the commissioning policy's own criteria, and the roughly 45-50 patients this represents are the defined switch-eligible population for next-generation therapy.

Avalglucosidase alfa (Nexviazyme) has since been recommended by NICE under TA821, with a confidential commercial arrangement, following an appraisal in which Sanofi presented two evidence scenarios: a switch indication for alglucosidase inadequate responders, and a first-line indication for treatment-naive LOPD patients. The COMET trial showed a 23.5-metre 6MWT improvement and preserved FVC against a 13.2-metre 6MWT decline for alglucosidase, a meaningful functional advantage. Avalglucosidase's WAC carries an estimated 20-30% premium over alglucosidase, so the NHS budget impact still depends on real-world uptake by population: for the 45-50-patient switch population, the incremental NHS budget impact is a manageable £2-4M per year; broader first-line uptake across all new LOPD patients would create a materially larger budget differential.