ABSTRACT
OBJECTIVE: To evaluate an alternative method of defining acute treatment success in migraine by combining multiple indicators into a single dichotomous measure of success. BACKGROUND: Migraine is characterized by a symptom complex; combining these features as a single endpoint may improve the measurement of treatment effects and better predict patient satisfaction with treatment. METHODS: We used a confirmatory latent class model (LCM) with two latent classes interpreted as treatment success and treatment failure. Pooled data for placebo and ubrogepant 50 mg from the ACHIEVE I and ACHIEVE II trials and data for ubrogepant 100 mg from ACHIEVE I were used. LCM inputs included pre-dose and 2-h post-dose measures of pain severity (0-3), the presence/absence of associated symptoms (nausea, photophobia, and phonophobia [0 or 1]), and functional disability (0-3). All definitions were validated against satisfaction with study medication (SWSM) at 24 h post-dose; results were compared with 2-hour pain freedom (2hPF). RESULTS: This pooled analysis included 2247 participants. At 2 h post-dose in the ubrogepant 50 and 100 mg dose groups, 53.2% (472/887) and 54.9% (246/448) of participants, respectively, were classified as achieving treatment success using the LCM-based approach, compared to 39.0% (356/912) of participants in the placebo group. The results for treatment success using the 2hPF endpoint were 20.7% (184/887) and 21.5% (96/447) in the ubrogepant 50 and 100 mg dose groups, respectively, compared to 12.7% (116/912) for placebo. Using 24-h SWSM as an external validator, the LCM approach sensitivity and correct classification rates were higher than for 2hPF. CONCLUSION: The LCM approach led to higher rates of treatment success and greater separation between ubrogepant and placebo and was a more sensitive predictor of treatment satisfaction than the regulatory endpoint of 2hPF.
