Budget Impact Analysis of Botulinum Toxin Type A for Patients with Severe Blepharospasm in Thailand.

Objective: Severe blepharospasm is a disabling neurological condition that significantly affects patients' quality of life. Botulinum toxin type A (BoNT-A) is considered the standard treatment due to its targeted therapeutic effect and fewer systemic side effects compared to oral medications. However, its high cost poses a barrier to access within Thailand's healthcare system. This study aimed to assess the budget impact of introducing BoNT-A treatment (Onabotulinumtoxin A and Abobotulinumtoxin A) compared with current oral medications for severe blepharospasm in Thailand. Methods: A budget impact model was developed from the perspective of Thailand's healthcare system over a 5-year time horizon. The current scenario (oral medications use) was compared with a new scenario involving BoNT-A treatment. The costs considered included drug acquisition, outpatient visits, and accident-related injuries. The base-case assumed gradual uptake of BoNT-A (30% in year 1, 50% in year 2, and 100% from year 3). Sensitivity analyses explored full uptake from year 1, no dose sharing, and inclusion of injury-related costs. Results: Excluding injury-related costs, the 5-year net budget impact (NBI) was 7.91 million THB (223,040 USD) for onabotulinumtoxin A and 7.27 million THB (205,064 USD) for abobotulinumtoxin A. Including injury-related costs reduced the NBI to 4.20 million THB (118,564 USD) and 3.57 million THB (100,588 USD), respectively. Without dose sharing, the NBI rose significantly, reaching 40.5 million THB (1.14 million USD) for abobotulinumtoxin A. Conclusion: BoNT-A treatment increases healthcare costs, primarily due to drug costs. However, reduced injury costs and dose-sharing strategies may enhance affordability and support BoNT-A's inclusion in Thailand's National List of Essential Medicine.