OBJECTIVES: For adults with cervical dystonia (CD), treatment with botulinum neurotoxin type A (BoNT-A) can improve achievement of treatment goals. Differences across individual BoNT-A therapies with respect to acquisition cost, response rates, and dosing frequency can have implications for healthcare spending and patient outcomes. The objective of this analysis was to evaluate average expenditures per response obtained with abobotulinumtoxinA (aboBoNT-A) and onabotulinumtoxinA (onaBoNT-A) for CD in Canada.

METHODS: A cost-effectiveness model was developed that incorporated data describing response rates in CD by BoNT-A therapy, health state utilities and health resource utilization by response status, and acquisition cost of BoNT-As in Canada. Response rates and dosing intervals were based on a prospective observational study comparing Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) scores for CD patients receiving aboBoNT-A (32.0%; 17.4 weeks) vs. onaBoNT-A (22.3%; 16.0 weeks). Health resource use by response status was based on a physician survey initially conducted in the United Kingdom and validated by Canadian physicians. Health state utilities by response status were based on published data reporting change from baseline in utility following BoNT-A treatment (0.60 vs. 0.76). Quality-adjusted life years (QALYs) were also adjusted for adverse events (AEs) associated with oral therapies that are utilized more frequently by BoNT-A non-responders. Probabilistic and one-way sensitivity analyses were conducted.

RESULTS: Compared with onaBoNT-A, aboBoNT-A resulted in lower annual costs per patient for the management CD (savings of $286), and higher QALYs (increase of 0.02). Results were driven by differences in injection intervals and a higher treatment response rate for people receiving aboBoNT-A compared with onaBoNT-A. Total cost per responder was lower for patients receiving aboBoNT-A compared with onaBoNT-A (CD: $11,701 vs $18,074). Results were consistent across sensitivity analyses.

CONCLUSIONS: With higher response rates and reduced costs, aboBoNT-A may be an optimal choice for treating cervical dystonia in Canada.