OBJECTIVES: Multiple sclerosis is a chronic autoimmune disease of the central nervous system, which results in inflammation, axonal transection, and demyelination. The primary objective of this study was to evaluate the incremental cost-effectiveness of cladribine tablets compared with an alternative disease-modifying drug (natalizumab, fingolimod, alemtuzumab) in the treatment of patients with active Relapsing-Remitting Multiple Sclerosis (RRMS).

METHODS: A cohort-based Markov state transition model was developed to simulate the costs and effectiveness of treatment in people with RRMS. For the Bulgarian base case, the key comparators were alemtuzumab, fingolimod, and natalizumab. Both costs and health outcomes were estimated for a lifetime horizon of 50 years and discounted at an annual rate of 5%.

RESULTS: Total cost per patient over the time horizon (50 years) for treating RRMS with alternatives was: cladribine tablets - 127 043,43 BGN (Bulgarian Lev), fingolimod - 178 264,84 BGN, natalizumab -145 141,36 BGN, alemtuzumab - 129 934,24 BGN, giving incremental cost for cladribine tablets versus comparators ranging from -12 805,35 (fingolimod); -4 524,48 BGN (natalizumab) to -722,7 BGN (almetuzumab). Incremental QALYs for cladribine tablets ranged from +0,08 (vs. natalizumab) to +0,4 (vs fingolimod). Therefore cladribine tablets dominate natalizumab and fingolimod. Alemtuzumab gained more QALY (+1,09) and higher per-patient cost versus cladribine tablets. Cladribine tablets are a cost-effective therapeutic option compared to alemtuzumab (ICER = 663,03 BGN/QALY).

CONCLUSIONS: From the Bulgarian NHIF perspective, cladribine tablets are the most cost-effective option in the treatment of RRMS as they dominate natalizumab and fingolimod and are a cost-effective strategy vs alemtuzumab.