DOES THE ELIGIBILITY RULE, NOT THE DRUG EFFECT, SET THE AFFORDABLE PRICE? A DIALYSIS-REVEALED COST-UTILITY ANALYSIS OF TOLVAPTAN IN ADPKD
Author(s)
Omar Maoujoud, MD, PhD1, Amal Yassine, MD, PhD1, Intissar Haddiya, MD, PhD2.
1ISPOR Morocco, Research Team of pharmacoeconomics & pharmacoepidemiology, Faculty of Medicine Mohammed V University, Rabat, Morocco, 2Department of Nephrology, Faculty of Medicine, Mohammed I University, Oujda, Morocco, Oujda, Morocco.
1ISPOR Morocco, Research Team of pharmacoeconomics & pharmacoepidemiology, Faculty of Medicine Mohammed V University, Rabat, Morocco, 2Department of Nephrology, Faculty of Medicine, Mohammed I University, Oujda, Morocco, Oujda, Morocco.
OBJECTIVES: Tolvaptan slows kidney decline in autosomal dominant polycystic kidney disease (ADPKD) but delays rather than prevents dialysis. Morocco has no official cost-effectiveness threshold, but AMO (mandatory insurance) reimburses dialysis, revealing the price per quality-adjusted life-year (QALY) the system accepts. We tested whether the payer's eligibility rule, not the drug effect, governs the price a treatment must reach to be cost-effective, using tolvaptan in ADPKD.
METHODS: We built a Markov cost-utility model in which patients progress through chronic kidney disease stages to dialysis and death, driven by each arm's eGFR slope (lifetime horizon, half-cycle correction, 3% discounting, MAD). The threshold came from dialysis spending: annual dialysis cost divided by dialysis utility (357,143 MAD/QALY). Because tolvaptan postpones dialysis, the saving was the difference between two time-shifted, mortality-truncated dialysis streams, not delay times full cost. We solved the price ceiling for two rules: rapid progressors only, and all-comers as a mix of rapid and low-risk patients. Uncertainty used 10,000 iterations, with dual-engine and Excel-to-Python validation.
RESULTS: The affordable price was 33,536 MAD/year for rapid progressors only (95% interval 16,852 to 52,623), but 14,316 for all-comers (-2,731 to 33,071). Restriction raised it in every iteration (P=1.00). The gain came not from rapid progressors being individually more valuable, but from avoiding low-risk patients, whose own price was negative (-11,374): they gain little but incur cost and side effects. Even the rapid-progressor price sat well below every imputed reference-price anchor, implying a reduction of roughly 50% to 60%.
CONCLUSIONS: The eligibility rule the payer adopts, not the size of the drug effect, sets the affordable price. Restricting to rapid progressors more than doubles what AMO can pay, but only if these patients can be identified in advance and the effect is durable. External reference pricing alone does not make tolvaptan affordable at the dialysis-revealed threshold.
METHODS: We built a Markov cost-utility model in which patients progress through chronic kidney disease stages to dialysis and death, driven by each arm's eGFR slope (lifetime horizon, half-cycle correction, 3% discounting, MAD). The threshold came from dialysis spending: annual dialysis cost divided by dialysis utility (357,143 MAD/QALY). Because tolvaptan postpones dialysis, the saving was the difference between two time-shifted, mortality-truncated dialysis streams, not delay times full cost. We solved the price ceiling for two rules: rapid progressors only, and all-comers as a mix of rapid and low-risk patients. Uncertainty used 10,000 iterations, with dual-engine and Excel-to-Python validation.
RESULTS: The affordable price was 33,536 MAD/year for rapid progressors only (95% interval 16,852 to 52,623), but 14,316 for all-comers (-2,731 to 33,071). Restriction raised it in every iteration (P=1.00). The gain came not from rapid progressors being individually more valuable, but from avoiding low-risk patients, whose own price was negative (-11,374): they gain little but incur cost and side effects. Even the rapid-progressor price sat well below every imputed reference-price anchor, implying a reduction of roughly 50% to 60%.
CONCLUSIONS: The eligibility rule the payer adopts, not the size of the drug effect, sets the affordable price. Restricting to rapid progressors more than doubles what AMO can pay, but only if these patients can be identified in advance and the effect is durable. External reference pricing alone does not make tolvaptan affordable at the dialysis-revealed threshold.
Conference/Value in Health Info
2026-11, ISPOR Europe 2026, Vienna, Austria
Value in Health, Volume 29, Issue 12S
Code
EE437
Topic
Economic Evaluation, Health Policy & Regulatory, Health Technology Assessment
Topic Subcategory
Thresholds & Opportunity Cost, Value of Information
Disease
Cardiovascular Disorders (including MI, Stroke, Circulatory), Rare & Orphan Diseases, Urinary/Kidney Disorders