OBJECTIVES: Certolizumab is a tumor necrosis factor alpha (TNF-⍺) blocker that improves the clinical signs and symptoms of rheumatoid arthritis. The aim of this study was to evaluate the cost effectiveness of certolizumab versus other TNF-⍺ blockers as add on therapy to methotrexate in the treatment of moderate to severe RA in Saudi Arabia.

METHODS: A Markov state transition model was developed to evaluate the cost utility (Cost/QALY) of certolizumab versus other TNF-⍺ blockers. Efficacy (ACR responses) and utility data were collected from published literature. Direct costs were derived from MOH and KSUMC costing data. This study was conducted from a healthcare provider perspective with 15 year time horizon, 6 months model cycle, and 3 % discounting rate. One-way and probabilistic sensitivity analysis were performed. The willingness to pay threshold was assumed to be ($ 70,590) which is 3 times the Saudi GDP per capital for 2019.

RESULTS: The base case analysis showed that the average lifetime costs for certolizumab, etanercept, adalimumab and infliximab in combination with methotrexate were $412,980, $423,620, $ 435,950, $ 422,303 respectively. In addition, certolizumab regimen had the highest QALY gains (7.11 QALYs) followed by etanercept, adalimumab, and infliximab regimens (6.97, 6.83, 6.35) respectively. The ICER of certolizumab regimen was $ 36,680 /QALY which dominated all other TNF-⍺ blockers regimens. The results sensitivity analysis were robust to changes in time horizon, discount rate, drug cost and sensitive to ACR responses (3months vs.6 months).

CONCLUSIONS: The result of this analysis indicates that the addition of certolizumab to methotrexate is considered cost effective compared to other TNF-⍺ blockers in moderate to severe RA patients in Saudi Arabia.