UK Pompe Disease HTA Strategy Model

NICE's Highly Specialised Technologies (HST) pathway, reserved for treatments of very rare conditions and the route available to Pompe disease given the UK's total 350-450 patients, accepts a QALY threshold of £100,000-300,000. A standard technology appraisal caps at £20,000-30,000 per QALY, five to fifteen times lower. Avalglucosidase alfa's TA821 recommendation (24 August 2022) tested that higher ceiling directly: the COMET trial's +23.5-metre six-minute-walk-test gain against alglucosidase's 13.2-metre decline translated into a modest per-patient QALY increment, and NICE's positive decision rested on a substantial confidential commercial arrangement that narrowed the ICER inside HST bounds. That arrangement reflects a negotiating position built on Sanofi's existing alglucosidase franchise and its installed base across the UK's 8 NHS Pompe Highly Specialised Service centres, not a comparator case a new entrant can assume it can replicate without that leverage.

A new entrant should not build its submission around matching or beating avalglucosidase's incremental FVC and 6MWT gains. That comparator route prices in an estimated £1M-4M per QALY before any commercial arrangement narrows it, a gap only Sanofi's existing franchise economics can close. A materially stronger NICE case exists in the anti-drug-antibody-positive (ADA+) inadequate-responder subgroup: an estimated 30-50 UK LOPD patients develop high-titre antibodies to alglucosidase and deteriorate, measured by FVC decline and cardiac hypertrophy progression, despite continued therapy. Positioned against a baseline of ongoing deterioration rather than incremental improvement, the QALY case strengthens further for the 80-120 UK LOPD patients on home non-invasive ventilation, the highest-urgency slice of that population. Avoiding ventilator dependency carries an estimated 0.36 QALY per year of ventilation avoided (EQ-5D utility approximately 0.32 on NIV versus 0.68 off it), evidence that clears the HST threshold on its own terms rather than by matching a rival's improvement margin.

Building that ADA+ case requires evidence NICE has not yet reviewed for Pompe disease. The British Inherited Metabolic Diseases Group's (BIMDG) Pompe subcommittee, six metabolic physicians drawn from the UK's 8 NHS Highly Specialised Service centres who advise NICE directly on Pompe appraisals, should be engaged 18-24 months before submission, at an estimated £50,000-100,000 over 2-3 years. That engagement runs alongside identifying the ADA+ and NIV-dependent cohorts themselves. Without a named population characterised by antibody titre and ventilation status, likely through a Royal Free London data-access partnership given its established Pompe cohort, there is no NICE-eligible group to submit against.

Every AXLRx HTA strategy model is built from primary HTA-body sources, NICE technology appraisals and NHS commissioning policy documents, not secondary summaries. Every comparator claim is pressure-tested through the 3-test defence framework before being accepted.

UK Pompe disease HTA sources: NICE TA821 (avalglucosidase alfa) decision document, NHS England's alglucosidase clinical commissioning policy, and BIMDG Pompe subcommittee guidance.