Cost-Effectiveness of the Personalization of Immunosuppresive Therapy in Kidney Transplantation by Means of an in Vitro Diagnostic Test (IMMUNOBIOGRAM®) in Spain

OBJECTIVES: Immunobiogram (IMBG) is an in vitro diagnostic (IVD) functional test that measures the immune cells pharmacodynamic response profile of each patient to individual immunosuppressants (IMS) in renal transplant. The objective was to estimate the cost-effectiveness of the use of IMBG for the Spanish National Health System (NHS).

METHODS: The evolution of a cohort of patients with kidney transplantation at least 1 year after transplantation (time horizon of 5 years) was simulated using a second-order Monte Carlo simulation for two scenarios: renal failure in patients with high immunological risk (HR), and adverse events (AE) in stable patients (non-HR). The transition probabilities were obtained from a clinical study with IMBG and a systematic review. The cost associated with graft failure (dialysis, re-transplantation), IMS and AE management were obtained from Spanish sources updated for 2023. The loss of utilities associated with graft rejection was obtained from the literature.

RESULTS: IMS adjustment, according to the IMBG could contribute to a risk reduction of graft failure with a saving per HR patient of €22,664 (95% CI €19,502-25,779) (100% saving probability). The expected reduction in the AE rate would generate savings per non-HR patient of €537 (95% CI €-484; 1,808) (80.6% saving probability). Compared with the option of not using IMBG, 0.0212 (95% CI 0.0117-0.0350) quality-adjusted life years (QALY) would be gained in each patient evaluated with IMBG. The probability that IMBG is the cost-effective option (for a willingness to pay of €25,000 per QALY gained) compared to the non-IMBG choice would be 85.4%. IMBG would be the cost-effective option with a reduction in the graft rejection rate (HR) above 2% of the current graft failure probability at 5 years.

CONCLUSIONS: According to the model, IMBG could be a cost-effective option from the NHS perspective, compared to the alternative without IMBG in kidney transplantation.