Headache care and anti-calcitonin gene-related peptide monoclonal antibodies in Japan: Insights from an online survey of 397 physician members of the Japanese Headache Society

Editor’s note: The research described below comes from a recipient of a 2024 MSC Travel Grant supporting travel to the 66th Annual Scientific Meeting of the American Headache Society. These grants reimburse travel expenses for those who have had their abstract for a presentation or poster accepted at a meeting.

By Keiko Ihara, MD, visiting researcher, Keio University School of Medicine, and junior resident, Japanese Red Cross Ashikaga Hospital, Japan

What is the research gap that your study addresses?

The anti-calcitonin gene-related peptide monoclonal antibodies (CGRP mAbs) are proven to be effective but are relatively expensive for migraine prevention. With two years of experience after their launch in Japan, it is now critical to understand the current situation of headache care and CGRP mAb use for further optimization of their use in the near future. The Japanese Headache Society guideline recommends prescribing CGRP mAbs in patients who have ≥4 monthly migraine days (MMDs) and ≥1 previous preventive failure; however, it remained unclear if clinicians had been able to start CGRP mAbs as early as the guideline.

What is your research hypothesis?

We expected that some patients would find CGRP mAbs too expensive and some physicians would hesitate to prescribe them. Given the large volume of patients and the limited number of headache care providers in Japan, we also hypothesized that many physicians would have limited time for each patient.

What methodology did you use to address your research hypothesis?

We conducted an online survey of Japanese Headache Society (JHS) members, which included approximately 3,000 physicians and 1,000 board-acquired headache specialists from December 2022 to January 2023. The timing of the survey was one year and eight months after the launch of the first CGRP mAb in Japan. The survey collected information including the following: the respondent’s type of facility, service, age, years of headache practice, years of JHS membership, board certification(s), the average length of the first/follow-up appointment for headache patients, the number of patients with migraine who were regularly followed up, the number of patients with migraine who had ever used migraine preventive treatments, the number of patients with migraine who had ever been treated with a CGRP mAb, the experience using CGRP mAbs, the availability of CGRP mAbs at each facility, the threshold of monthly migraine days for recommending a CGRP mAb, the number of migraine preventives usually tried before a CGRP mAb was prescribed, the point at which to assess the response to a CGRP mAb for patients, the percentages of patients whose monthly migraine days had decreased by ≥ 50%, the most frequently reported reason for CGRP mAb responders to discontinue CGRP mAbs, and any requests related to CGRP mAbs.

What are the main results of your study?

Of the 397 respondents, 320 had prescribed CGRP mAbs. Only 8.3% used the earliest possible threshold of 1 preventive failure and 4 monthly migraine days (MMDs) for starting CGRP mAbs. The threshold of preventive failures was 2 in 55%. The MMD threshold was dispersed between 4-10. Cost (90 USD/month) was the most frequently mentioned answer as the request for CGRP mAbs, and the most frequently reported reason for responders to discontinue CGRP mAbs.

The clinicians regularly followed up with a median of 30 patients with migraine. The average lengths of the first and follow-up appointments of headache patients were 23.5 min and 9.0, respectively.

What conclusions did you reach based on your results?

We revealed that most of the respondents were prescribed CGRP mAbs with more restrictive thresholds than JHS guidelines, possibly due to financial concerns. We also demonstrated that physicians regularly take care of a large volume of patients with a limited length of each appointment.

What are the limitations of your study?

We provided comprehensive data on headache practice; however, only 13% of the physicians submitted responses to this survey. The respondents may have included several physicians from the same clinic/hospital, which may have affected the results. Additionally, similar surveys should be conducted internationally to improve the quality of headache care worldwide.

What is the relevance of your study to migraine?

This study focused on headache clinical practice and the use of anti-CGRP monoclonal antibodies, a new migraine-specific therapy that was approved in 2021 in Japan. We demonstrated that the financial burden of this therapy on patients with migraine might be associated with its suboptimal use. Further optimization of guidelines or financial support for patients with migraine is necessary to make the most of this new medication class in Japan.

CGRP-monoclonal antibodies in Japan: insights from an online survey of physician members of the Japanese headache society.
Takizawa T, Ihara K, Watanabe N, Takemura R, Takahashi N, Miyazaki N, Shibata M, Suzuki K, Imai N, Suzuki N, Hirata K, Takeshima T, Nakahara J.
J Headache Pain. 2024 Mar 15;25(1):39.