RESUMO
BACKGROUND AND OBJECTIVES: As regression approaches have been used more recently to model the effectiveness and health-related quality of life (HRQOL) of novel migraine treatments, an example is provided for fremanezumab. The objective is to estimate the distribution of mean monthly migraine days (MMD) as a continuous variable and corresponding migraine-specific utility values as a function of the MMD, to inform health states in a cost-effectiveness model (CEM). METHODS: Three longitudinal regression models (zero-adjusted gamma [ZAGA], zero-inflated beta-binomial [ZIBB], and zero-inflated negative binomial [ZINBI]) were fitted to Japanese-Korean clinical trial data of episodic (EM) and chronic migraine (CM) patients treated with fremanezumab or placebo, to estimate MMD over a period of 12 months. The EQ-5D-5L and the migraine-specific quality-of-life (MSQ), mapped to the EQ-5D-3L, questionnaires were used to measure HRQOL. Migraine-specific utility values were estimated as a function of MMD using a linear mixed effects model. RESULTS: The ZIBB models fitted the data best in estimating the distribution of mean MMD over time. MSQ-derived values were more sensitive than the EQ-5D-5L values for the effect of the number of MMD on HRQOL, with higher values for less MMD and more time on treatment. CONCLUSIONS: Using longitudinal regression models to estimate MMD distributions and linking utility values as a function is an appropriate method to inform CEMs and capture inter-patient heterogeneity. The observed distribution shifts demonstrated fremanezumab's effect at reducing MMD for both EM and CM patients, while treatment effect on HRQOL was captured by MMD and time on treatment.
The current study provides an example of an approach that can be used to estimate the number of migraine days per month and the quality of life of migraine patients. The outcomes of this approach can give an impression of how well a patient reacts to a new migraine treatment called fremanezumab. In this study, different mathematical equations were used to measure the migraine days per month and quality of life over a period of 1 year. The data came from Japanese-Korean patients that participated in clinical trials. The patients reported the number of days that they had migraine and their quality of life was measured with two validated questionnaires. With the gathered data, the quality of life was calculated for the number of migraine days that a patient could have per month. Patients who had the fewest migraine days and were treated the longest with the new treatment reported the best quality of life. The investigated approach is an appropriate method to measure the impact of fremanezumab on the number of monthly migraine days and a patient's quality of life. The measurements of this approach can be linked to other parameters in an economic model to estimate the costs required to reach a certain level of treatment effect with this new migraine treatment.
