(97) A cost per responder analysis of ritlecitinib and baricitinib: assessing the impact of clinical efficacy and dosing variability on overall treatment costs of severe alopecia areata

Background: : Ritlecitinib, a Janus kinase (JAK) 3/tyrosine kinase expressed in hepatocellular carcinoma family kinase inhibitor, and baricitinib, a JAK 1/2 inhibitor, are approved for the treatment of severe alopecia areata (AA). Ritlecitinib is available as a single daily dose of 50 mg, and baricitinib as 2 mg and 4 mg daily.

Objective: : To develop a cost per responder (CPR) analysis for ritlecitinib and baricitinib for the treatment of severe AA to estimate the budget impact of these new therapies resulting from differences in clinical efficacy, available dosages, and pricing structure.

Methods: : A decision tree evaluated cost implications of once-daily ritlecitinib 50 mg, or baricitinib 2 mg and 4 mg treatment across a 1-year time horizon from a US perspective. Drug costs were estimated using wholesale acquisition costs. 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% (SALT Δ ≥30%) at Weeks 18 and 24, and longer-term treatment response as absolute SALT score ≤20 at Weeks 36 and 52. Patients initiating baricitinib 2 mg who did not have shorter-term treatment response were allowed to up-titrate to 4 mg or discontinue therapy. Decision probabilities were derived from RWE and clinical trial data.

Results: : At Week 24, 52.10% of ritlecitinib 50 mg initiators and 36.28% of baricitinib 2/4 mg initiators achieved SALT Δ ≥30%; at Week 52, 40.26% and 30.63% of ritlecitinib 50 mg and baricitinib 2/4 mg initiators, respectively, achieved SALT ≤20. Baricitinib 2/4 mg had a higher CPR than ritlecitinib 50 mg 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 initiating 2 mg treatment. Sensitivity analyses showed ritlecitinib 50 mg CPR was lower at Week 24 (difference: −$1,532) and higher at Week 52 (difference: $10,728) than only baricitinib 2 mg use, and lower at Weeks 24 and 52 (difference: −$20,001 and −$60,073) than only baricitinib 4 mg use.

Conclusions: : Ritlecitinib 50 mg demonstrated a lower CPR than baricitinib 2/4 mg at Weeks 24 and 52. The straightforward dosing strategy and demonstrated potential cost savings from this analysis support reimbursement or formulary inclusion of ritlecitinib for the treatment of AA. Given the modelling approach, the results may be sensitive to response assessment timepoints and up-titration timing, which may vary in clinical practice.

Sponsorship:: Pfizer Inc