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We thank the authors of the letter for sharing their views on this article. We pursued the publishing of these data in an attempt to clearly define and further characterize patients with a monthly response rate of 100% to galcanezumab. The purpose of this article was to dispel the very notion that a significant number of patients had 100% response across the entire treatment period, which the authors of the Letter to the Editor raised. The title is meant to reflect the article content related to the characterization of patients with episodic migraine who achieved 100% monthly response (ie, 100% reduction from baseline in monthly migraine headache days) to galcanezumab treatment. The use of the terms “response rate” and “responder rates” is standard terminology used in clinical trials/clinical trial guidelines for migraine preventive therapies (http://www.ihs-headache.org/binary_data/158_clinical-trials-controlled-trials-of-drugs-in-migraine3rd-ed-cha.pdf). Whether speaking of ≥50%, ≥75%, or 100% reduction of migraine headache days, the terms “response rate” and “responder rates” are common and appropriate terminology to use. We disagree with the suggestion by the authors’ Letter to the Editor that the month-by-month analysis was unconventional or the results presented, which included the odds ratios, were misleading. The primary and secondary outcomes for these trials, such as the number of monthly migraine headache days and the proportions of patients with ≥50%, ≥75%, or 100% response, were measured monthly (at each visit). These outcomes capture the patients’ response during any given month between 2 separate doses. In this paper, we presented the observed as well as the model-estimated number and proportions of patients with 100% response at each month (Supplemental Table S1 and Fig. 1, respectively) from a generalized linear mixed effects model estimate. This well-accepted model is a robust method of analyzing longitudinal data in clinical trials and is basically a mixed-models repeated measures version of a logistic regression (a standard analysis approach for binary outcomes for which odds ratios are readily available). The primary analysis approach of looking at the average across months yields a standard measure of monthly response seen by patients across the entire dosing month period. Such an estimate is neither biased toward higher response seen in the later months of treatment nor overly penalized by the lower responses observed in the earlier months of treatment. What is represented is the estimated proportions of patients who are expected to have a 100% response (ie, 0 migraine headache days) on an average month (averaged across all visits) and is not the same as the proportions of patients with 100% response in any 1 out of the 6 months. The proportions of patients with at least 1 month with 100% response is approximately 40%. In addition to presenting the Headache doi: 10.1111/head.13514 © 2019 Eli Lilly & Co. Published by Wiley Periodicals, Inc. ISSN 0017-8748