UK IgA Nephropathy Payer & HTA

Budesonide (Tarpeyo, Calliditas/AstraZeneca) is NICE-recommended and NHS-funded under TA937, with eligibility subsequently expanded by TA1128 (February 2026). Its NefIgArd trial data showed a 31% reduction in urine protein-to-creatinine ratio and a 3.87 mL/min/year eGFR-slope benefit; the economic case NICE accepted turns on that eGFR benefit translating into a meaningful delay to end-stage renal disease — at a median GFR of 60 mL/min/year at diagnosis, the modelled ESRD delay is 5–8 years. NHS renal replacement therapy costs an estimated £37,000 a year in dialysis, so a 5–8 year delay implies £185,000–£296,000 in NHS savings per patient against a drug cost of £175,000–£360,000 over the same period at a WAC of £35,000–£45,000 a year, a case NICE judged close to breakeven and cleared with a Patient Access Scheme discount understood to be in the 20–35% range off WAC against its standard £20,000–£30,000/QALY threshold.

Before either novel agent could qualify for funding, NICE's guidance requires patients to have completed ACEi/ARB optimisation for at least three months, with a target proteinuria below 0.5 g/g and blood pressure below 130/80mmHg, per Renal Association and KDIGO guidelines — a standard-of-care gate that an estimated 70% of the 10,000–15,000 UK IgAN patient pool partially clears, leaving 3,000–5,000 patients with persistent proteinuria above 0.5–1.0 g/g as the addressable novel-agent population. At £35,000–£45,000 a year across that population, potential NHS annual spend reaches £140–180 million, a budget-impact scale that carries a Patient Access Scheme or Commercial Access Agreement on both agents regardless of clinical case. Sparsentan (Filspari, Travere) received MHRA marketing authorisation in April 2025 and NICE's final recommendation in May 2025; its PROTECT trial confirmatory data showed a smaller eGFR decline (−2.0 mL/min/year vs −4.7 for placebo) and superior proteinuria reduction (−49.8% vs budesonide's −31%), a competitive position it now holds as an NHS-available alternative within the same cost-effectiveness envelope as budesonide.

This assessment is built from NICE's IgAN economic modelling framework, NHS renal replacement therapy tariff data, published NefIgArd and PROTECT trial results, and Renal Association/KDIGO guideline documentation defining the standard-of-care gate.

Key sources: NICE IgAN economic model framework (GID appraisal documentation); NHS RRT tariff, 2023–24; NefIgArd trial eGFR and UPCR data; Renal Association IgA Nephropathy guideline, 2023; NICE TA937 (budesonide), since updated by TA1128, Feb 2026; NICE final guidance on sparsentan, May 2025; NICE TA775 (dapagliflozin for CKD), since updated by TA1075; KDIGO 2021 guideline; PROTECT trial 2-year confirmatory data, 2024; UK Renal Registry IgAN patient flow model, 2023; NICE budget impact methodology. Devolved-nation positions (Scotland's SMC, Wales's AWMSG) are assessed against NICE's now-established English precedent for both agents.