OBJECTIVE: To develop a cost-per-responder (CPR) analysis for ritlecitinib and baricitinib for the treatment of severe AA to address uncertainties in budget impact of these new therapies resulting from differences in clinical efficacy and available dosages.
METHODS: A decision tree evaluated cost implications of once-daily ritlecitinib 50mg, or baricitinib 2mg and 4mg treatment across a 1-year time horizon from a US perspective. Drug costs were estimated by wholesale acquisition cost. Distribution across treatment and dosing options was based on real-world evidence (RWE). Shorter-term treatment response was defined as Severity of Alopecia Tool (SALT) score relative change from baseline ≥30% (SALT30) at Weeks 18 and 24, and longer-term treatment response as absolute SALT score ≤20 at Weeks 36 and 52. Patients initiating baricitinib 2mg who did not meet treatment response in the shorter term were allowed to up-titrate to 4mg or discontinue therapy. Decision probabilities were derived from RWE and clinical trial data.
RESULTS: At Week 24, 52.10% of ritlecitinib initiators and 36.28% of baricitinib initiators achieved SALT30; at Week 52, 40.26% and 30.63% of ritlecitinib and baricitinib initiators, respectively, achieved SALT ≤20. Baricitinib had a higher CPR than ritlecitinib at Weeks 24 ($54,887 vs $45,577) and 52 ($107,217 vs $94,834). Cost-equivalence was reached at Week 52 at $38,180 with 42.72% of baricitinib patients at 2mg. Sensitivity analyses showed ritlecitinib CPR was lower at Week 24 (difference: −$1,532) and higher at Week 52 (difference: $10,728) than only baricitinib 2mg use, and lower at Weeks 24 and 52 (difference: −$20,001 and −$60,073) than only baricitinib 4mg use.
CONCLUSION: Ritlecitinib is more cost-effective per responder than baricitinib at Weeks 24 and 52. These findings support reimbursement or formulary inclusion of ritlecitinib for the treatment of AA. Given the modelling approach, results may be sensitive to response assessment timepoints and up-titration timing, which may vary in clinical practice.
