Table 3 Criteria for assessing the effectiveness of CGRP(-receptor) targeted mAbs and recommendations for stopping the treatment according to different organisations. Abbreviations: CGRP = calcitonin gene-related peptide; MHD = monthly headache days; MIDAS = Migraine Disability Assessment Test; MPFID = Migraine Physical Function Impact Diary; HIT-6 = Headache Impact Test- 6

European Headache Federation (EHF) [7]

• Efficacy should be assessed after at least three months of treatment

• In EM or CM, a pause in the treatment should be considered after 12 to18 months

• Treatment should be continued as long as needed

• Restart the treatment if migraine worsens after withdrawal

American Headache Society (AHS) [95]

• Reduction in mean MHDs or headache days of at least moderate severity of at least 50% compared to baseline (documented)

• A significant improvement in ANY of the following:

MIDAS

- Reduction of ≥ 5 points when baseline score is 11 to 20

- Reduction of ≥ 30% when baseline score is > 20

MPFID

- Reduction of ≥ 5 points

HIT-6

- Reduction of ≥ 5 points

• Efficacy should be assessed after at least three months of treatment for drugs administered monthly and at least six months for drugs administered quarterly

• Treatment should be continued only if criteria for effectiveness are met

Germany Society of Neurology and German Migraine and Headache Society [96]

• Reduction in the mean MHDs by ≥ 50% compared to baseline for at least three months (documented) or

• Significant improvement in the following:

- 30% reduction in MIDAS when baseline score is above 20

- Reduction of ≥ 5 points in HIT-6

• Efficacy should be assessed after at least three months of treatment

• Treatment should be continued only if criteria for effectiveness are met

• Termination of the therapy should be again considered after six to nine months

French Headache Society [97]

• Reduction of MHDs by:

- 50% in EM

- 30% in CM

• Reduction of acute treatments, intensity and duration of attacks

• Improvement of quality of life

• Efficacy should be assessed during the third month of treatment (weeks 8 to 12)

• Termination of treatment should be considered due to insufficient efficacy and/or tolerability

• Treatment should be continued for 6 to 12 months, then decreased slowly before considering termination

• Treatment should be restarted if the frequency of attacks increases again during decrease or after cessation

Danish Headache Society [98]

• Reduction of ≥ 50% in the frequency or severity of migraine

• No bothersome side effects

• Efficacy should be assessed after at least two to three months of treatment

• Treatment should be terminated if it is not tolerated due to side effect

• Treatment should be assessed for discontinuation every 6 to 12 months

Polish Headache Society, the Headache Section of the Polish Neurological Society and the Polish Pain Society [99, 100]

At least one of the following:

• Reduction in MHDs/MMDs of 50% compared to baseline (documented)

• Improvement in MIDAS score of ≥ 5 points, when a baseline score is 11 to 20

• Reduction in MIDAS score of 30% when a baseline score is close to 20 or a functional improvement in other scores (e.g. MPFID, HIT-6), or improvement documented in the patient’s diary

• Efficacy should be assessed after approximately six months

• Treatment should be discontinued if the frequency of attacks remains stable, with a gradual dose reduction

• In case of a recurrence of frequent migraine attacks, dose escalation and the continuation of therapy for the next six to nine months are recommended