Sibeprenlimab-szsi / voyxact for reducing proteinuria in adults with primary IgA nephropathy

As of February 2026, MARA’s assessment finds Sibeprenlimab-szsi / VOYXACT’s reimbursement risk concentrated in quality of life, with patient population and subgroups a strength; the current MARA Rating and full rationale are available in the report.

The assessment also weighs cost effectiveness: whether the price asked stands in a defensible relationship to the benefit delivered — the core of most European reimbursement decisions. The strength recorded in patient population and subgroups carries weight because that domain asks how closely the trial population matches the patients who would receive the drug in practice; payers often restrict funding to the groups where the evidence is strongest.

Nephrology

This rating sits within MARA’s Nephrology coverage, alongside 16 other independently assessed treatments in the same area.

What payers will ask

Is the clinical benefit the kind payers reward? — Clinical effectiveness

The evidence from the phase 3 VISIONARY trial shows a significant reduction in proteinuria with a 50% decrease in the uPCR-24h ratio compared to placebo, which indicates a moderate benefit over current care. However, the FDA label notes that long-term clinical benefit has not been established, which limits the strength of the evidence.

Does the economic case hold at the expected price? — Cost effectiveness

The ICER report indicates a very high ICER of $894,000 per QALY gained, which is well above typical thresholds for cost-effectiveness, suggesting poor value for the treatment.

Is there quality-of-life evidence payers weigh? — Quality of life

No validated HRQoL outcomes were reported in the pivotal trials or the FDA label, indicating a complete absence of evidence regarding the impact of sibeprenlimab on quality of life.

Does the safety profile hold up for payers? — Safety and Adverse Effects

The safety profile shows that adverse events were mostly mild to moderate, with a high percentage of patients experiencing adverse events but no significant safety concerns compared to placebo. Serious adverse events were low, indicating good tolerability.

Was the drug compared against what payers expect? — Comparator Selection

The trials used placebo as a comparator, which is acceptable but does not provide a direct comparison to other active treatments for IgAN, limiting the robustness of the evidence.

Is the population defined the way payers need it? — Patient Population and Subgroups

The trial population is broadly representative of the intended patient population with a diverse demographic and relevant clinical characteristics, although subgroup analyses were limited.

Does the drug fit how care is delivered and paid for? — Care Pathway Integration

The treatment can be integrated into existing care pathways with minimal adjustments, as it is administered subcutaneously every four weeks and does not require significant changes to current practices.

Are the wider system costs understood? — Resource Use and Cost Implications

The annual net price of $292,500 raises concerns about the affordability and budget impact, indicating a high resource burden that may require restrictions.

Would the evidence survive payer scrutiny? — Evidence Quality and Robustness

The evidence is based on rigorous phase 2 and phase 3 trials with clear endpoints and statistical significance, although the long-term outcomes remain uncertain.

How exposed is the case to uncertainty? — Uncertainty, Sensitivity, and Broader Impacts

There is significant uncertainty regarding the long-term benefits of the treatment, as indicated by the FDA’s accelerated approval status and the need for confirmatory evidence.

This assessment is part of MARA’s coverage of market access risk in IgA nephropathy.

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Public record

The entries below are official decisions and assessments concerning this drug and indication, listed with their dates as a matter of record. The assessment on this page reflects the evidence available as of its date.

26 February 2026 — United States (ICER), evidence report: adequate evidence of net health benefit versus no immunomodulatory therapy. official record

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