Safety and Tolerability of 3 CGRP Monoclonal Antibodies in Practice: A Retrospective Cohort Study

Anti‑CGRP monoclonal antibodies in resistant migraine: preliminary real-world effectiveness and clinical predictors of response at two years

BACKGROUND

Monoclonal antibodies targeting calcitonin gene-related peptide (anti-CGRP mAbs) have shown clinical effectiveness and safety in randomized clinical studies. However, long-term studies in clinical practice remain limited.

AIM

To assess the long-term effectiveness, clinical predictors and safety of three anti-CGRP mAbs (erenumab, galcanezumab, fremanezumab) in resistant migraine patients.

METHOD

A single-center retrospective study was conducted from December 2019 to June 2023 involving 120 resistant migraine patients who received at least a month of anti-CGRP mAbs treatment. Patients completed a headache diary that included monthly acute medication intake (MAM), monthly migraine days (MMD), adverse events as well as completed Patient-Reported Outcome questionnaires (MIDAS [Migraine Disability Assessment] and Headache Impact Test 6 [HIT-6]). The number of patients achieving a ≥ 50% reduction in monthly migraine days was determined and classified as ≥ 50% responders, and baseline parameters and logistic regression between responders and non-responders were analyzed to identify potential predictors of response. Adverse events were registered in every follow-up.

RESULTS

Treatment with anti-CGRP mAbs led to reductions in MIDAS, HIT-6, MMD and MAM from baseline to 6-24 months. At 6-12 months, responders (61% and 57%, respectively) exhibited lower baseline MMD and MAM. Medication overuse  was associated with non-responders from 6 to 24 months and it was identified as a negative predictor of treatment effectiveness (OR 0.23, 95% CI 0.07-0.74; p = 0.014).

CONCLUSION

Anti-CGRP mAbs prove effectiveness and safety over a 24-month period in a RM population. Patients with no medication overuse and lower basal MMDs and MAM may respond better to anti-CGRP mAbs.

Comparative effectiveness and tolerability of calcitonin gene-related peptide (CGRP) monoclonal antibodies and onabotulinumtoxinA in chronic migraine: A multicenter, real-world study in Taiwan

OBJECTIVE

To compare the real-world effectiveness and tolerability of calcitonin gene-related peptide (CGRP) monoclonal antibodies (mAbs) and onabotulinumtoxinA in chronic migraine (CM) patients.

METHODS

This multicenter study involved retrospective analysis of prospectively collected data of CM patients treated with CGRP mAbs or onabotulinumtoxinA, including difficult-to-treat (DTT) patients (i.e., ≥3 preventive failures). Treatment outcomes were determined at 6 months based on prospective headache diaries and Migraine Disability Assessment (MIDAS).

RESULTS

The study included 316 (55 M/261F, mean age 44.4 ± 13.5 years) and 333 (61 M/272F, mean age 47.9 ± 13.4 years) CM patients treated with CGRP mAbs or onabotulinbumtoxinA, respectively. At 6 months, CGRP mAb treatment was associated with a greater decrease in monthly migraine days (MMDs) (-13.0 vs. -8.7 days/month, p < 0.001) and a higher ≥50% responder rate (RR) (74.7% vs. 50.7%, p < 0.001) compared with onabotulinumtoxinA injections. The findings were consistent in DTT patients (-13.0 vs. -9.1 MMDs, p < 0.001; ≥50% RR: 73.9% vs. 50.3%, p < 0.001) or those with medication-overuse headache (MOH) (-13.3 vs. -9.0 MMDs, p < 0.001; ≥50% RR: 79.0% vs. 51.6%, p < 0.001). Besides, patients receiving CGRP mAbs had greater improvement (-42.2 vs. -11.8, p < 0.001) and a higher ≥50% RR (62.0% vs. 40.0%, p = 0.001) in MIDAS scores and a lower rate of adverse events (AEs) (6.0% vs. 21.0%, p < 0.001). However, none of the patients discontinued treatment due to AEs.

CONCLUSIONS

In this multicenter, real-world study, CGRP mAbs were more effective than onabotulinumtoxinA in CM patients, even in DTT or MOH patients. All of these injectables were well tolerated. Further prospective studies are needed to verify these findings.

Treatment Outcome After Switching From Galcanezumab to Fremanezumab in Patients With Migraine

BACKGROUND AND PURPOSE

Monoclonal antibodies (mAbs) targeting calcitonin-gene-related peptide (CGRP) or its receptor (anti-CGRP-R) have been widely administered to patients with migraine who show inadequate responses to preventive medications. Among patients in whom a particular anti-CGRP-R mAb is ineffective, switching between different anti-CGRP-R mAbs can be the next option. Few studies have investigated treatment outcomes for antibody switching, especially between mAbs with the same target of the CGRP ligand. We aimed to determine the treatment outcome after switching between two anti-CGRP mAbs (galcanezumab to fremanezumab).

METHODS

We identified migraine patients in a prospective headache clinic registry who received galcanezumab for ≥3 months and were switched to fremanezumab for a further ≥3 months at a single university hospital. We defined a treatment response as a ≥50% reduction in the number of days with a moderate or severe headache at the third month of treatment relative to baseline. The treatment response after switching to fremanezumab was compared with the initial treatment response to galcanezumab.

RESULTS

Among 21 patients identified in the registry, 7 (33.3%) were initial responders to galcanezumab. After switching to fremanezumab, 7 (33.3%) showed a treatment response. The treatment response rate was 28.6% in the initial responders and 71.4% in the nonresponders to galcanezumab (p>0.999).

CONCLUSIONS

Switching between anti-CGRP mAbs (galcanezumab to fremanezumab) yielded a treatment outcome comparable to that reported previously when switching from an anti-CGRP-R mAb (erenumab) to an anti-CGRP mAb (galcanezumab or fremanezumab). The treatment response to fremanezumab seems to be independent of the prior treatment response to galcanezumab. Our findings suggest that switching to another anti-CGRP mAb can be considered when a particular anti-CGRP mAb is ineffective or intolerable.

Effectiveness of Switching CGRP Monoclonal Antibodies in Non-Responder Patients in the UAE: A Retrospective Study

Calcitonin gene-related peptide monoclonal antibodies (CGRP mAbs) have shown promising effectiveness in migraine management compared to other preventative treatment options. Many questions remain regarding switching between antibody classes as a treatment option in patients with migraine headaches. This preliminary retrospective real-world study explored the treatment response of patients who switched between CGRP mAb classes due to lack of efficacy or poor tolerability. A total of 53 patients with migraine headache switched between three of the CGRP mAbs types due to lack of efficacy of the original prescribed CGRP mAbs, specifically eptinezumab, erenumab, and galcanezumab. Fremanezumab was not included due to unavailability in the UAE. Galcanezumab and eptinezumab target the CGRP ligand (CGRP/L), while erenumab targets CGRP receptors (CGRP/R). The analysis of efficacy demonstrated that some improvements were seen in both class switch cohorts (CGRP/R to CGRP/L and CGRP/L to CGRP/R). The safety of switching between CGRP classes was well observed, as any adverse events presented before the class switch did not lead to the discontinuation of treatment following the later switch. The findings of this study suggest that switching between different classes of CGRP mAbs is a potentially safe and clinically viable practice that may have some applications for those experiencing side effects on their current CGRP mAb or those witnessing suboptimal response.

Real-world experience with calcitonin gene-related peptide-targeted antibodies for migraine prevention: a retrospective observational cohort study at two Japanese headache centers

BACKGROUND

Although randomized controlled trials (RCTs) have shown that calcitonin gene-related peptide (CGRP)-targeted monoclonal antibodies (CGRP mAbs) are an efficacious and safe therapeutic modality for migraine prevention, their clinical benefits have not been well validated in Japanese patients in the real-world setting. The present study aimed to evaluate the real-world efficacy and safety of galcanezumab, fremanezumab, and erenumab in Japanese patients with migraine.

METHODS

This observational retrospective cohort study was conducted at two headache centers in Japan. Patients with migraine who had experienced treatment failure with at least one traditional oral migraine preventive agent were treated with a CGRP mAb de novo. The primary efficacy endpoints were the changes from baseline in monthly migraine days (MMDs) and Headache Impact Test-6 (HIT-6) score after 3 dosing intervals (V3). We explored whether demographic and clinical characteristics predicted therapeutic outcomes at V3.

RESULTS

Sixty-eight patients who completed three doses of a CGRP mAb (85.3% female [58/68], mean age: 46.2 ± 13.1 years) were included in the analysis. There were 19 patients with chronic migraine. The baseline MMDs were 13.4 ± 6.0. After 3 doses, the MMDs significantly decreased to 7.4 ± 5.5 (p < 0.0001), and the 50% response rate was 50.0%. HIT-6 score was significantly reduced from 66.7 ± 5.4 to 56.2 ± 8.7 after 3 doses (P = 0.0001). There was a positive correlation between the changes in MMDs and HIT-6 score from baseline after 2 doses (p = 0.0189). Those who achieved a ≥ 50% therapeutic response after the first and second doses were significantly more likely to do so at V3 (crude odds ratio: 3.474 [95% CI: 1.037 to 10.4], p = 0.0467). The most frequent adverse event was constipation (7.4%). None of the adverse events were serious, and there was no need for treatment discontinuation.

CONCLUSIONS

This real-world study demonstrated that CGRP mAbs conferred Japanese patients with efficacious and safe migraine prevention, and an initial positive therapeutic response was predictive of subsequent favorable outcomes. Concomitant measurement of MMDs and HIT-6 score was useful in evaluating the efficacy of CGRP mAbs in migraine prevention.

Adverse event reporting of four anti-Calcitonin gene-related peptide monoclonal antibodies for migraine prevention: a real-world study based on the FDA adverse event reporting system

Background: Anti-Calcitonin gene-related peptide monoclonal antibodies (anti-CGRP mAbs) have shown significant efficacy in preventing migraine. However, there have been limited reports of adverse events (AEs) after marketing, particularly for eptinezumab launched in 2020. The study aimed to mine and analyze the AE signals with four anti-CGRP mAbs from the United States Food and Drug Administration (FDA) Adverse Event Reporting System (FAERS) database to gain insights into the safety profile of these medications post-marketing. Methods: All AE reports on the four anti-CGRP mAbs (erenumab, galcanezumab, fremanezumab, and eptinezumab) were retrieved from the FAERS database from the first quarter (Q1) of 2018 to Q1 of 2023. Disproportionality analysis was measured by reporting odd ratio (ROR) and Bayesian confidence propagation neural network (BCPNN) to identify potential AE signals. Comparisons were made between the four drugs in terms of AEs. Results: A total of 38,515 reports of erenumab, 19,485 reports of galcanezumab, 5,332 reports of fremanezumab, and 2,460 reports of eptinezumab were obtained, mostly reported in the second to third year after launch in the market. The common AEs to erenumab included constipation (17.93%), injection site pain (14.08%), and alopecia (7.23%). The AEs that occurred more frequently with galcanezumab included injection site pain (24.37%), injection site erythema (5.35%), and injection site haemorrhage (4.97%). Common AEs related to fremanezumab were injection site pain (13.10%), injection site erythema (7.02%), and injection site pruritus (5.47%). Fatigue (13.54%), throat irritation (9.02%), and pruritus (8.20%) were the most common AEs with eptinezumab. In addition, there are new AEs that were not listed in the drug instructions but occurred concurrently with multiple drugs, such as Raynaud's phenomenon, weight increase, menstrual disorders, throat tightness, and paraesthesia oral. Conclusion: Common AE signals of the four anti-CGRP mAbs and new AE signals were found to provide a reference for clinical drug selection in clinical practice.

Pharmacological characterisation of erenumab, Aimovig, at two calcitonin gene-related peptide responsive receptors

BACKGROUND AND PURPOSE

Calcitonin gene-related peptide (CGRP) is involved in migraine pathophysiology. CGRP can signal through two receptors. The canonical CGRP receptor comprises the calcitonin receptor-like receptor and receptor activity-modifying protein 1 (RAMP1); the AMY1 receptor comprises the calcitonin receptor with RAMP1. Drugs that reduce CGRP activity, such as receptor antagonists, are approved for the treatment and prevention of migraine. Despite being designed to target the canonical CGRP receptor, emerging evidence suggests that these antagonists, including erenumab (a monoclonal antibody antagonist) can also antagonise the AMY1 receptor. However, it is difficult to estimate its selectivity because direct comparisons between receptors under matched conditions have not been made. We therefore characterised erenumab at both CGRP-responsive receptors with multiple ligands, including αCGRP and βCGRP.

EXPERIMENTAL APPROACH

Erenumab antagonism was quantified through IC50 and pKB experiments, measuring cAMP production. We used SK-N-MC cells which endogenously express the human CGRP receptor, and HEK293S and Cos7 cells transiently transfected to express either human CGRP or AMY1 receptors.

KEY RESULTS

Erenumab antagonised both the CGRP and AMY1 receptors with an ~20-120-fold preference for the CGRP receptor, depending on the cells, agonist, analytical approach and/or assay format. Erenumab antagonised both forms of CGRP equally, and appeared to act as a competitive reversible antagonist at both receptors.

CONCLUSION AND IMPLICATIONS

Despite being designed to target the CGRP receptor, erenumab can antagonise the AMY1 receptor. Its ability to antagonise CGRP activity at both receptors may be useful in better understanding the clinical profile of erenumab.

Real-world effectiveness of fremanezumab for the preventive treatment of migraine: Interim analysis of the pan-European, prospective, observational, phase 4 PEARL study

BACKGROUND

The ongoing Pan-European Real Life (PEARL) phase 4 study is evaluating fremanezumab effectiveness and safety for the prevention of episodic and chronic migraine. This interim analysis reports primary, secondary and exploratory endpoints from when 500 participants completed at least six months of treatment.

METHODS

Adults with episodic migraine or chronic migraine maintaining daily headache diaries were enrolled upon initiation of fremanezumab. Primary endpoint: proportion of participants with ≥50% reduction in monthly migraine days during the six-month period after fremanezumab initiation. Secondary endpoints: mean change from baseline across months 1-12 in monthly migraine days, acute migraine medication use, and headache-related disability. Exploratory endpoint: mean change in headache severity from baseline across months 1-12. Safety was assessed through adverse events reported.

RESULTS

Overall, 897 participants were enrolled and 574 included in the effectiveness analyses (episodic migraine, 25.8%; chronic migraine, 74.2%). Of participants with data available, 175/313 (55.9%) achieved ≥50% monthly migraine days reduction during the six-month period post-initiation. Across months 1-12, there were sustained reductions in mean monthly migraine days, acute medication use, disability scores, and headache severity. Few adverse events were reported.

CONCLUSION

PEARL interim results support the effectiveness and safety of fremanezumab for migraine prevention in a real-world population across several European countries.Trial registration: encepp.eu: EUPAS35111.

Effectiveness of Calcitonin Gene-Related Peptide Monoclonal Antibodies in the Prevention of Migraine: A Systematic Review and Meta-Analysis of Observational Cohort Studies

BACKGROUND AND OBJECTIVE

Migraine is a neurological disorder characterized by episodes of moderate-to-severe headache. The emergence of drugs derived from monoclonal antibodies specific for the calcitonin gene has brought forth a therapeutic option for patients in whom the traditional treatments have failed. This study aimed to evaluate the clinical effectiveness of calcitonin gene-related peptide antibodies in the prevention of migraine through a systematic review and meta-analysis of observational cohort studies.

METHODS

A literature search for evidence was performed in electronic databases for observational studies that evaluated adult patients with migraine receiving calcitonin gene-related peptide receptor antagonists (e.g. erenumab, fremanezumab, galcanezumab and eptinezumab) and reported effectiveness outcomes (mean reduction in monthly migraine/headache days, and proportion of patients with 50% or greater reduction in migraine/headache days).

RESULTS

During the screening process, 47 records were included for data extraction and qualitative and quantitative analyses. The overall rate of patients with a reduction of at least 50% of mean monthly migraine days was 54% (95% CI 49-59%), and overall mean monthly migraine reduction was about 7.7 days (95% CI 8.4-7.0 days). Regarding the outcome ≥ 50% reduction in mean monthly headache reduction, the overall rate of patients with a reduction of at least 50% was 57% (95% CI 48-64%), and the overall mean monthly headache reduction was approximately 8.8 days (95% CI 10.1-7.5 days). Subgroup analyses considering the drug treatment used and type of migraine were consistent with previous results.

CONCLUSIONS

The use of calcitonin gene-related peptide antibodies in real-world studies to prevent migraine demonstrates promising effectiveness outcomes, in agreement with those reported in previously published randomized clinical trial reports.

Effectiveness and safety of anti-CGRP monoclonal antibodies in patients over 65 years: a real-life multicentre analysis of 162 patients

BACKGROUND

Anti-CGRP monoclonal antibodies have shown notable effectiveness and tolerability in migraine patients; however, data on their use in elderly patients is still lacking, as clinical trials have implicit age restrictions and real-world evidence is scarce. In this study, we aimed to describe the safety and effectiveness of erenumab, galcanezumab and fremanezumab in migraine patients over 65 years old in real-life.

METHODS

In this observational real-life study, a retrospective analysis of prospectively collected data from 18 different headache units in Spain was performed. Migraine patients who started treatment with any anti-CGRP monoclonal antibody after the age of 65 years were included. Primary endpoints were reduction in monthly migraine days after 6 months of treatment and the presence of adverse effects. Secondary endpoints were reductions in headache and medication intake frequencies by months 3 and 6, response rates, changes in patient-reported outcomes and reasons for discontinuation. As a subanalysis, reduction in monthly migraine days and proportion of adverse effects were also compared among the three monoclonal antibodies.

RESULTS

A total of 162 patients were included, median age 68 years (range 65-87), 74.1% women. 42% had dyslipidaemia, 40.3% hypertension, 8% diabetes, and 6.2% previous cardiovascular ischaemic disease. The reduction in monthly migraine days at month 6 was 10.1 ± 7.3 days. A total of 25.3% of patients presented adverse effects, all of them mild, with only two cases of blood pressure increase. Headache and medication intake frequencies were significantly reduced, and patient-reported outcomes were improved. The proportions of responders were 68%, 57%, 33% and 9% for reductions in monthly migraine days ≥ 30%, ≥ 50%, ≥ 75% and 100%, respectively. A total of 72.8% of patients continued with the treatment after 6 months. The reduction in migraine days was similar for the different anti-CGRP treatments, but fewer adverse effects were detected with fremanezumab (7.7%).

CONCLUSIONS

Anti-CGRP mAbs are safe and effective treatments in migraine patients over 65 years old in real-life clinical practice.

A head-to-head observational cohort study on the efficacy and safety of monoclonal antibodies against calcitonin gene-related peptide for chronic and episodic migraine

OBJECTIVE

To compare the effectiveness and safety of galcanezumab, fremanezumab, and erenumab for the treatment of chronic and episodic migraine, through real-world data.

BACKGROUND

Monoclonal antibodies (mAbs) targeting the calcitonin gene-related peptide (CGRP) pathway have been tested extensively in several clinical trials for both episodic and chronic migraine, showing high effectiveness, safety, and tolerability; however, there are no prospective real-world studies intending to compare their efficacy and safety.

METHODS

This is a prospective observational cohort study comparing the effectiveness and safety profiles of galcanezumab, fremanezumab, and erenumab for the treatment of chronic and episodic migraine. We enrolled 140 patients at the Headache Centre of University Federico II of Naples, with a history of multiple failed treatments with validated migraine preventatives. Framenezumab, erenumab, or galcanezumab were administered for 12 months. The mean monthly days with headache, Migraine Disability Assessment (MIDAS) score, and adverse events were evaluated during the run-in period and every 3 months by reviewing standardized paper patient headache diaries.

RESULTS

We found a mean reduction of migraine monthly days from baseline of -12.0 (-9.8, -14.1) in the galcanezumab group, -12.3 (-10.2, -14.3) in the fremanezumab group, and -10.8 (-8.5, -13.1) in the erenumab group (for all, p < 0.001). We found a mean reduction of MIDAS score of -32.6 (-26.6, -38.5) in the galcanezumab group, -33.4 (-28.0, -38.9) in the fremanezumab group, and -29.2 (-23.0, -35.4) in the erenumab group (for all, p < 0.001). We found no significant differences between mAbs in the reduction of mean monthly days with headache and MIDAS score. We found a more rapid effect of galcanezumab and erenumab compared to fremanezumab in medication overuse headache patients after 3 months of treatment (-10.8 and -11.1 vs. -4.0 days; p = 0.029).

CONCLUSION

Our results confirm the therapeutic benefits of anti-CGRP mAbs. There is no evidence that suggests that one antibody may be superior to the others in terms of effectiveness, both in chronic and episodic patients.

Review of Tolerability of Fremanezumab for Episodic and Chronic Migraine

Calcitonin gene-related peptide (CGRP) monoclonal antibodies (mAbs) were the first class of medication specifically developed for the prevention of migraine. Fremanezumab is one of four CGRP mAbs currently available and is approved by the US Food and Drug Administration (FDA) for the preventative treatment of episodic and chronic migraines. This narrative review summarizes the history of fremanezumab development, the trials that led to its approval, and the later studies published evaluating its tolerability and efficacy. Evidence of fremanezumab for clinically significant efficacy and tolerability in patients with chronic migraine is especially important when considering the high level of disability, lower quality of life scores, and higher levels of health-care utilization associated with this condition. Multiple clinical trials demonstrated superiority of fremanezumab over placebo in terms of efficacy while demonstrating good tolerability. Treatment-related adverse reactions did not differ significantly compared to placebo and dropout rates were minimal. The most commonly observed treatment-related adverse reaction was mild-to-moderate injection site reaction, described as erythema, pain, induration, or swelling at the injection site.

Real-world evidence of galcanezumab for migraine treatment in Japan: a retrospective analysis

OBJECTIVE

To evaluate the efficacy and safety of galcanezumab in patients with migraine in a real-world setting in Japan.

BACKGROUND

Galcanezumab is the first anti-calcitonin gene-related peptide monoclonal antibody approved in Japan. To the best of our knowledge, no real-world studies on galcanezumab have been published in any international journal from Japan.

METHODS

We retrospectively examined patients with migraine who received three doses of galcanezumab between August 2021 and February 2022 at the Keio University Hospital. We assessed changes in monthly migraine days, responder rate, and migraine-associated and premonitory symptoms. We also investigated injection site reactions and adverse events.

RESULTS

Fifty-two patients received three doses of galcanezumab during the study period. Compared with those at baseline, the monthly migraine days decreased by 5.9 days (95% confidence interval, 4.2-7.7) at 3 months. The 50% responder rate was 61.5% at 3 months. A total of 64.9%, 50.0%, and 63.9% of patients showed improvement in the severity of photophobia, phonophobia, and nausea/vomiting, respectively. Premonitory symptoms without subsequent headache were reported in 62.5% of patients. Moreover, injection site reaction was the most common adverse event (34.6%).

CONCLUSION

This study revealed the efficacy and safety of galcanezumab for migraineurs in Japan. Galcanezumab also improved migraine-associated symptoms. However, despite a reduction in headaches, premonitory symptoms without subsequent headache were reported in > 50% of the patients at 3 months.

Monoclonal Antibodies against Calcitonin Gene-Related Peptide for Migraine Prophylaxis: A Systematic Review of Real-World Data

OBJECTIVE

To perform a systematic review of real-world outcomes for anti-CGRP-mAbs.

METHODS

Following the PRISMA guidelines, we searched PubMed for real-world data of erenumab, galcanezumab, fremanezumab, or eptinezumab in patients with migraines.

RESULTS

We identified 134 publications (89 retrospective), comprising 10 pharmaco-epidemiologic and 83 clinic-based studies, 38 case reports, and 3 other articles. None of the clinic-based studies provided follow-up data over more than one year in more than 200 patients. Findings suggest that there are reductions in health insurance claims and days with sick-leave as well as better treatment adherence with anti-CGRP-mAbs. Effectiveness, reported in 77 clinic-based studies, was comparable to randomized controlled trials. A treatment pause was associated with an increase in migraine frequency, and switching to another antibody resulted in a better response in some of the patients. Adverse events and safety issues were addressed in 86 papers, including 24 single case reports.

CONCLUSION

Real-world data on anti-CGRP-mAbs are limited by retrospective data collection, small patient numbers, and short follow-up periods. The majority of papers seem to support good effectiveness and tolerability of anti-CGRP-mAbs in the real-world setting. There is an unmet need for large prospective real-world studies providing long-term follow-ups of patients treated with anti-CGRP-mAbs.

Commentary: Constipation caused by anti-calcitonin gene-related peptide migraine therapeutics explained by antagonism of calcitonin gene-related peptide’s motor-stimulating and prosecretory function in the intestine

Calcitonin gene-related peptide (CGRP) pathway-targeted treatments have been shown to be efficacious in the prevention of episodic and chronic migraine. Currently approved therapies include monoclonal antibodies (mAbs) that target CGRP (eptinezumab, fremanezumab, and galcanezumab) and the CGRP receptor (erenumab), and small molecule CGRP receptor antagonists (atogepant and rimegepant). While CGRP pathway–targeted treatments are generally well-tolerated, in a review article by Holzer and Holzer-Petsche published in the January 2022 issue of Frontiers in Physiology the authors discussed the role of the CGRP pathway in gastrointestinal physiology, with a specific focus on constipation associated with the use of CGRP pathway–targeted treatments. The authors state that real-world surveys have shown constipation to be a “major adverse event” reported in “more than 50% of patients treated with erenumab, fremanezumab or galcanezumab.” As described in the current commentary, the limited data from the cited references in the review article by Holzer and Holzer-Petsche do not support that statement.

A stated preference survey to explore patient preferences for novel preventive migraine treatments

OBJECTIVE

The objective of this study was to explore patient preference for attributes of calcitonin gene-related peptide (CGRP) inhibitors for the preventive treatment of migraine and to describe differences in treatment preferences between patients.

BACKGROUND

CGRP inhibitors are a novel class of migraine drugs specifically developed for the preventive treatment of migraine. Clinicians should understand patient preferences for CGRP inhibitors to inform and support prescribing choices.

METHODS

Patients with migraine in the US and Germany were recruited to participate in an online discrete choice experiment (DCE) survey, which presented hypothetical treatment choices using five attributes: mode of administration, side effects, migraine frequency, migraine severity, and consistency of treatment effectiveness. Attribute selection was informed by a literature review and semi-structured patient interviews (n = 35), and evaluated using patient cognitive debriefing interviews (n = 5).

RESULTS

Of 680 who consented to participate, 506 participants completed the survey and were included in the study (US = 257; Germany = 249). Overall, participants placed highest importance (preference weight, beta = 1.65, p < 0.001) on the treatment's ability to reduce the severity of migraine (mild vs. unchanged severity), followed by consistent treatment effectiveness (beta = 1.13, p < 0.001), and higher chance of reduced migraine frequency (beta = 1.00, p < 0.001). Participants preferred an oral tablet every other day (beta = 1.00, p < 0.001) over quarterly infusion, quarterly injections (p = 0.019), or monthly injection (p < 0.001). Preference for all treatment attributes were heterogeneous, and the subgroup analyses found that participants naïve to CGRP monoclonal antibody treatments had a stronger preference for oral therapy compared to those with such experience (p = 0.006).

CONCLUSION

In this DCE assessing CGRP inhibitors attributes, the main driver of patient choice was treatment effectiveness, specifically reduced migraine severity, and consistent treatment effectiveness. Further, patients exhibited an overall preference for an oral tablet every other day over injectables. Patients' experience with previous treatments informs the value they place on treatment characteristics.

A narrative review of the calcitonin peptide family and associated receptors as migraine targets: Calcitonin gene-related peptide and beyond

OBJECTIVE

To summarize the pharmacology of the calcitonin peptide family of receptors and explore their relationship to migraine and current migraine therapies.

BACKGROUND

Therapeutics that dampen calcitonin gene-related peptide (CGRP) signaling are now in clinical use to prevent or treat migraine. However, CGRP belongs to a broader peptide family, including the peptides amylin and adrenomedullin. Receptors for this family are complex, displaying overlapping pharmacologic profiles. Despite the focus on CGRP and the CGRP receptor in migraine research, recent evidence implicates related peptides and receptors in migraine.

METHODS

This narrative review summarizes literature encompassing the current pharmacologic understanding of the calcitonin peptide family, and the evidence that links specific members of this family to migraine and migraine-like behaviors.

RESULTS

Recent work links amylin and adrenomedullin to migraine-like behavior in rodent models and migraine-like attacks in individuals with migraine. We collate novel information that suggests females may be more sensitive to amylin and CGRP in the context of migraine-like behaviors. We report that drugs designed to antagonize the canonical CGRP receptor also antagonize a second CGRP-responsive receptor and speculate as to whether this influences therapeutic efficacy. We also discuss the specificity of current drugs with regards to CGRP isoforms and how this may influence therapeutic profiles. Lastly, we emphasize that receptors related to, but distinct from, the canonical CGRP receptor may represent underappreciated and novel drug targets.

CONCLUSION

Multiple peptides within the calcitonin family have been linked to migraine. The current focus on CGRP and its canonical receptor may be obscuring pathways to further therapeutics. Drug discovery schemes that take a wider view of the receptor family may lead to the development of new anti-migraine drugs with favorable clinical profiles. We also propose that understanding these related peptides and receptors may improve our interpretation regarding the mechanism of action of current drugs.

Measuring interictal burden among people affected by migraine: a descriptive survey study

BACKGROUND

Previous research has extensively documented the impact of migraine episodes ('ictal') on patients' health-related quality of life. Few studies have looked at the impact of migraine on migraine-free days ('interictal'). This study was designed to describe interictal burden of migraine in a mixed group of people affected by migraine and to explore patient characteristics associated with interictal burden.

METHODS

People with migraine in the United States (US) and Germany were recruited for a cross-sectional online survey, including a subgroup treated with calcitonin gene-related peptide (CGRP) monoclonal antibody (mAb). The survey included the Migraine Interictal Burden Scale (MIBS-4), Headache Impact Test (HIT-6), and items measuring patient demographics, clinical and treatment background. Data were analyzed using descriptive statistics and linear regression.

RESULTS

Five hundred six people with migraine completed the survey (US: n = 257; Germany: n = 249), of whom 195 had taken a CGRP mAb for three or more months. Participants had a mean of 8.5 (SD = 6.4) Monthly Migraine Days (MMD) and 10.4 (SD = 7.1) Monthly Headache Days (MHD). The mean MIBS-4 score was 6.3 (SD = 3.4), with 67% reporting severe interictal burden (MIBS-4: ≥5). The mean HIT-6 score was 65.3 (SD = 6.0), with 86% reporting severe migraine impact (HIT-6: ≥60). MIBS-4 was correlated with the HIT-6 (r = 0.37), MMD and MHD (both r = 0.27). The HIT-6, MMD, MHD, CGRP mAb treatment, and depression all had an independent positive association with the MIBS-4.

CONCLUSION

Two-thirds of the study sample reported substantial interictal burden. Whilst interictal burden was associated with migraine frequency and impact of migraine attacks, study results also show it represented a distinct aspect of the overall disease burden. Study findings further indicate unique associations between interictal burden and depression. A unique positive association between interictal burden and CGRP mAb treatment suggests a remaining unmet need among people affected by migraine treated with CGRP mAb.

Reducing the Burden of Migraine: Safety and Efficacy of CGRP Pathway-Targeted Preventive Treatments

Migraine is a highly disabling and often chronic neurological disease that affects more than one billion people globally. Preventive migraine treatment is recommended for individuals who have frequent and/or disabling attacks; however, many of the medications used for migraine prevention (e.g., antiepileptics, antidepressants, antihypertensives) were not specifically developed for migraine, and often have limited efficacy or poor tolerability. Four monoclonal antibodies targeting the calcitonin gene-related peptide (CGRP) pathway, which is believed to play a crucial role in the pathophysiology of migraine, have been approved by the US Food and Drug Administration for the preventive treatment of migraine in adults. All four migraine-specific treatments have demonstrated efficacy based on reductions in monthly days with migraine for patients with both episodic and chronic migraine, including those with comorbidities. They have also demonstrated favorable safety and tolerability profiles. Based on these accounts, CGRP pathway-targeted monoclonal antibodies have the potential to revolutionize preventive treatment for patients with migraine.

Brazilian descriptive study of 104 consecutive real-world migraine patients treated with monoclonal antibodies

BACKGROUND

Migraine is a highly disabling and prevalent neurological disorder. A peptide, calcitonin gene-related peptide, was identified as involved in migraine pathophysiology and monoclonal anti-CGRP antibodies have been developed.

AIM

To describe the clinical characteristics and therapeutic response of migraine patients treated with monoclonal antibodies.

METHOD

An observational, prospective, uncontrolled and descriptive study was carried out with a sample of 112 consecutive patients with episodic or chronic migraine treated with monoclonal antibodies. Eight patients did not return for the following medical consultation. They were excluded from the study.

RESULTS

A total of 104 patients were described. There was a predominance of episodic migraine. Before treatment, the average frequency of headache was 15.3±8.5 days per month, during the previous three months. Monoclonal antibodies were prescribed at the following frequency: erenumab (49%), galcanezumab (45.2%), and fremanezumab (5.8%). After the third month, the reduction in headache attacks was greater than 50% in 57.7% of patients. Adverse events were referred by 18.3% of patients, in this order of frequency: constipation (7.7%), insomnia (2.9%), vertigo (1.9%), erythema at the injection site (1.9%), arthralgia (1%), nasopharyngitis (1%), facial and hand edema (1%), irritation at the injection site (1%), and paresthesia at the injection site (1%).

CONCLUSIONS

This described analysis of migraine patients who used monoclonal antibodies presented one of the first Brazilian experiences with real-world patients. Our results may enlighten clinicians on the outcomes and ways of prescribing anti-CGRP antibodies.

Real-world effectiveness after initiating fremanezumab treatment in US patients with episodic and chronic migraine or difficult-to-treat migraine

Background

Fremanezumab, a fully humanized monoclonal antibody (mAb; IgG2Δa) that selectively targets calcitonin gene-related peptide (CGRP), is approved for the preventive treatment of migraine in adults. The efficacy and safety of fremanezumab for migraine prevention have been demonstrated in randomized, double-blind, placebo-controlled trials. Real-world effectiveness data are needed to complement clinical trial data. This study assessed the effectiveness of fremanezumab across different subgroups of adult patients with episodic migraine (EM), chronic migraine (CM), or difficult-to-treat (DTT) migraine in real-world clinical settings.

Methods

This retrospective, panel-based online chart review used electronic case report forms. Patient inclusion criteria were a physician diagnosis of EM or CM; age ≥ 18 years at the time of first fremanezumab initiation; ≥ 1 dose of fremanezumab treatment; ≥ 1 follow-up visit since first initiation; and ≥ 2 measurements of monthly migraine days (MMD; with 1 within a month before or at first initiation and ≥ 1 after first initiation). Changes in MMD and monthly headache days were assessed during the follow-up period. These endpoints were evaluated in subgroups of patients by migraine type (EM/CM) and in subgroups with DTT migraine (diagnosis of medication overuse [MO], major depressive disorder [MDD], generalized anxiety disorder [GAD], or prior exposure to a different CGRP pathway–targeted mAb [CGRP mAb]).

Results

Data were collected from 421 clinicians and 1003 patients. Mean (percent) reductions from baseline in MMD at Month 6 were − 7.7 (77.0%) in EM patients, − 10.1 (68.7%) in CM patients, − 10.8 (80.6%) in the MO subgroup, − 9.9 (68.3%) in the MDD subgroup, − 9.5 (66.4%) in the GAD subgroup, and − 9.0 (68.7%) in the prior CGRP mAb exposure subgroup. Improvements in MDD or GAD severity were reported by 45.5% and 45.8% of patients with comorbid MDD or GAD, respectively.

Conclusions

In this real-world study, fremanezumab demonstrated effectiveness for migraine regardless of migraine type or the presence of factors contributing to DTT migraine (MO, GAD, MDD, or prior exposure to a different CGRP mAb).

Supplementary Information

The online version contains supplementary material available at 10.1186/s10194-022-01415-x.

CGRP Targeting Therapy for Chronic Migraine-Evidence from Clinical Trials and Real-world Studies

PURPOSE OF REVIEW

Monoclonal antibodies against calcitonin gene-related peptide (CGRP) or its receptor have become part of the standard treatment for migraine in clinical practice. The current review focuses on the clinical evidence of CGRP monoclonal antibodies in patients with chronic migraine (CM), including more challenging cases.

RECENT FINDINGS

CGRP monoclonal antibodies were more effective than placebo in reducing the number of monthly migraine days (MMDs), and the change relative to placebo in the treatment group was between - 1.2 and - 2.7 days at 3 months. CGRP monoclonal antibodies resulted in ≥ 50% response in 27.5 to 61.4% of patients, and doubled the odds for having ≥ 50% response. The findings were generally consistent in patients with coexisting medication overuse or with treatment failures to multiple preventive medications, including onabotulinumtoxinA. The results from real-world studies (RWS) were similar to those seen in clinical trials, and the changes from baseline in the number of MMDs and the response rates largely fell within the ranges of those reported in the treatment group in pivotal trials. The therapeutic effects typically started within a few days, and remained steady after regular treatment for up to 1 year. These agents were generally well tolerated, and the discontinuation rates due to adverse events in clinical trials and in many RWS were < 4.5%. CGRP monoclonal antibodies are effective and safe in the treatment of patients with CM, including clinical challenging cases. However, the role of CGRP monoclonal antibodies in a number of conditions, such as cardiovascular or cerebrovascular diseases, pregnancy, and overuse of opioids or barbiturates, needs to be further clarified.

Real-world effectiveness of fremanezumab in migraine patients initiating treatment in the United States: results from a retrospective chart study

Background

The efficacy and tolerability of fremanezumab, a fully humanized monoclonal antibody (IgG2Δa) that selectively targets calcitonin gene-related peptide (CGRP) and is approved for the preventive treatment of migraine in adults, have been demonstrated in randomized, double-blind, placebo-controlled trials. Real-world data can further support those clinical trial data and demonstrate the full clinical benefits of fremanezumab. This chart review assessed the effectiveness of fremanezumab for improving clinical outcomes in adult patients with migraine treated according to real-world clinical practice.

Methods

This retrospective, panel-based, online physician chart review study used electronic case report forms with US physicians. Patient inclusion criteria were a physician diagnosis of migraine, fremanezumab treatment initiation at ≥ 18 years of age after US Food and Drug Administration approval, ≥ 1 dose of fremanezumab treatment, and ≥ 2 assessments of monthly migraine days (MMD; 1 within 30 days before treatment initiation and ≥ 1 after initiation). Changes from baseline in MMD, monthly headache days (MHD), and Migraine Disability Assessment (MIDAS) and 6-item Headache Impact Test (HIT-6) scores were assessed over 6 months. These endpoints were evaluated in the overall population and subgroups divided by dosing schedule and number of prior migraine preventive treatment failures.

Results

This study included data from 421 clinicians and 1003 patients. Mean age at fremanezumab initiation was 39.7 years, and most patients were female (75.8%). In the overall population, mean baseline MMD and MHD were 12.7 and 14.0, respectively. Mean (percent) reductions from baseline in MMD and MHD, respectively, were − 4.6 (36.2%) and − 4.7 (33.6%) at Month 1, − 6.7 (52.8%) and − 6.8 (48.6%) at Month 3, and − 9.2 (72.4%) and − 9.8 (70.0%) at Month 6. Mean (percent) reductions from baseline in MIDAS and HIT-6 scores also increased over the 6-month study period, from − 6.2 (21.6%) and − 8.4 (14.0%) at Month 1 to − 18.1 (63.1%) and − 16.2 (27.0%) at Month 6, respectively. Improvements in these outcomes over 6 months were observed across all evaluated subgroups.

Conclusions

This real-world study demonstrated effectiveness of fremanezumab treatment for up to 6 months, irrespective of dosing regimen or number of prior migraine preventive treatment failures, reflecting ongoing, clinically meaningful improvements in patient outcomes.

Supplementary Information

The online version contains supplementary material available at 10.1186/s10194-022-01411-1.

Effectiveness and safety of erenumab and galcanezumab in the prevention of chronic and episodic migraine: A retrospective cohort study

WHAT IS KNOWN AND OBJECTIVE?: Erenumab and galcanezumab have shown great results for migraine prevention. However, strict inclusion criteria, absence of concomitant medication and selective outcome report of clinical trials may sometimes be barely representative of the real-world daily practice. Therefore, this study was designed to evaluate effectiveness and safety of these two monoclonal antibodies targeting calcitonin gene-related peptide in real-world patients. METHODS: This observational, retrospective study evaluated the effectiveness and safety of erenumab 140 mg and galcanezumab 120 mg in 142 real-world patients who had previously not responded to three well-established pharmacological alternatives for migraine prevention. To do so, a combination of objective parameters (monthly headache days and acute migraine-specific medication days) and subjective measurements (Migraine Disability Assessment questionnaire, Headache Impact Test and Visual Analogue Scale), validated for clinical research in migraine, were assessed during clinical interview. RESULTS AND DISCUSSION: Findings here reported show that erenumab and galcanezumab reduced monthly headache days, acute migraine specific medication days per month, Headache Impact Test score, Migraine Disability Assessment Test score and Visual Analogue Scale score after 3 and 6 doses (p < 0.01). Additionally, more than 25% of the patients enrolled in the study experienced a reduction by a half in monthly headache days, and more than 50% of the patients also reported a reduction by a half in the number of migraine specific medication days. Both treatments exhibited a great safety profile, rarely leading to discontinuation because of poor tolerance. WHAT IS NEW AND CONCLUSIONS?: Altogether, these results support previous real-life studies regarding effectiveness and safety and provide an interesting insight in how these preventive therapies are also effective in patients diagnosed with difficult to treat migraine who have previously failed, at least, three different drug classes stablished by current neurology guidelines for migraine prevention. Moreover, these data may suggest that erenumab and galcanezumab are able to not only diminish frequency, but also migraine intensity, and that it should be also considered as an effectiveness measure in line with other authors suggestion.

Constipation Caused by Anti-calcitonin Gene-Related Peptide Migraine Therapeutics Explained by Antagonism of Calcitonin Gene-Related Peptide's Motor-Stimulating and Prosecretory Function in the Intestine

The development of small-molecule calcitonin gene-related peptide (CGRP) receptor antagonists (gepants) and of monoclonal antibodies targeting the CGRP system has been a major advance in the management of migraine. In the randomized controlled trials before regulatory approval, the safety of these anti-CGRP migraine therapeutics was considered favorable and to stay within the expected profile. Post-approval real-world surveys reveal, however, constipation to be a major adverse event which may affect more than 50% of patients treated with erenumab (an antibody targeting the CGRP receptor), fremanezumab or galcanezumab (antibodies targeting CGRP). In this review article we address the question whether constipation caused by inhibition of CGRP signaling can be mechanistically deduced from the known pharmacological actions and pathophysiological implications of CGRP in the digestive tract. CGRP in the gut is expressed by two distinct neuronal populations: extrinsic primary afferent nerve fibers and distinct neurons of the intrinsic enteric nervous system. In particular, CGRP is a major messenger of enteric sensory neurons which in response to mucosal stimulation activate both ascending excitatory and descending inhibitory neuronal pathways that enable propulsive (peristaltic) motor activity to take place. In addition, CGRP is able to stimulate ion and water secretion into the intestinal lumen. The motor-stimulating and prosecretory actions of CGRP combine in accelerating intestinal transit, an activity profile that has been confirmed by the ability of CGRP to induce diarrhea in mice, dogs and humans. We therefore conclude that the constipation elicited by antibodies targeting CGRP or its receptor results from interference with the physiological function of CGRP in the small and large intestine in which it contributes to the maintenance of peristaltic motor activity, ion and water secretion and intestinal transit.

Erenumab for Migraine Prevention in a 1-Year Compassionate Use Program: Efficacy, Tolerability, and Differences Between Clinical Phenotypes

During a 1-year compassionate use program, 156 patients with migraine self-administered a monthly dose of erenumab 140 mg with a subcutaneous autoinjector. Main inclusion criteria were: ≥ 4 migraine days/month and ≥two prior prophylactic treatment failures. The patients covered the migraine severity spectrum from episodic migraine (EM) (n = 80) to chronic migraine (CM) (n = 76). During the 3rd month of treatment, monthly headache days decreased by 45.7% in EM and 35.5% in CM. The 50% responder rate for reduction in monthly headache days was significantly higher in EM (55%) than in CM (43%) (p = 0.05). In both the migraine subgroups, the clinical improvement vs. baseline was already significant during the 1st month of treatment (p < 0.001). There were also significant reductions in mean headache severity, duration, and monthly days with acute drug intake. The 30% responder rate at 3 months was 60% in CM and 54.1% of patients reversed from CM to EM. The therapeutic effect was maintained at 12 months when 50% responder rates, considering discontinuation for lack of efficacy or adverse effects as 0% response, still were 51% in EM and 41% in CM. A total of 10 patients with EM (12.5%) and 23 patients with CM (30.3%) had discontinued treatment, considering the treatment as ineffective. At 3 months, 48% of patients reported non-serious adverse events among which the most frequent was constipation (20.5%); corresponding figures at 12 months were 30 and 15%. Discontinuation due to an adverse effect for the entire 12 month period was rare (3.8%). The lower efficacy in CM than in EM was mainly due to a very low 50% responder rate in patients with CM with continuous pain (13%) as compared to CM with pain-free periods (58%) (p < 0.001). Similarly, the 50% responder rate was lower in patients with ≥two prior prophylactic treatment failures (40.5%) compared to those with two failures (70%) (p < 0.05). There was no significant efficacy difference between low (4-7 migraine days/month, n = 22) and high frequency (8-14 days, n = 59) EM nor between patients with CM with (n = 50) or without (n = 26) acute medication overuse. Erenumab had no effect on the frequency of auras. Taken together, erenumab 140 mg monthly was highly effective for migraine prophylaxis over the whole severity spectrum of the disease, except in patients with continuous headaches. Its effect is significant after the first injection, quasi-maximal after the second injection, and does not wear off after 12 months. The most frequent adverse effect was constipation. These results are compared to those published for erenumab in the pivotal randomized placebo-controlled trials and to those reported in several recent real-world studies.

Effect of antibody switch in non-responders to a CGRP receptor antibody treatment in migraine: A multi-center retrospective cohort study

BACKGROUND

Switching between antibody classes might be a treatment option in migraine patients who have not responded to one class of a CGRP-(receptor) monoclonal antibody (mAb), but there are no efficacy data so far. In this real-world analysis, we assessed the treatment response to a CGRP-mAb in patients that have previously failed the CGRP-receptor-mAb erenumab.

METHODS

We analyzed retrospective headache diary data of 78 patients with migraine who switched between CGRP-mAbs classes at four German headache centers either due to lack of efficacy or intolerable side effects. Among these, we identified 25 patients who did not respond to erenumab after three treatment cycles (defined as <30% reduction of monthly headache days) and had complete headache documentation at least one month before and during both treatments. We assessed the ≥30% responder rate at month three after switching from erenumab to a CGRP-mAb (galcanezumab or fremanezumab) (primary endpoint). Secondary endpoints included ≥50% responder rate, monthly headache days, and monthly days with acute medication use. In an exploratory subgroup analysis patients were stratified for daily and non-daily headache.

RESULTS

The switch from erenumab to a CGRP-mAb led to a ≥30% response in one-third (32%) of the patients after three treatment cycles. A ≥50% response was achieved in 12% of the patients. Monthly headache days were reduced in month three compared to baseline (20.8 ± 7.1 to 17.8 ± 9.1; p = 0.009). Stratified analysis revealed that no patient with daily headache (n = 9) responded to the treatment switch, while a 30% response was achieved by 50% of patients with non-daily headache (n = 16).

CONCLUSION

Our findings demonstrate that a relevant proportion of erenumab non-responders might benefit from a treatment switch to a CGRP-mAb. Switching seems to be a promising treatment option especially in migraine patients with non-daily headache.

Safety and tolerability of preventive treatment options for chronic migraine

INTRODUCTION

Relative to migraine generally, chronic migraine (CM) imposes greater disability, healthcare utilization and socioeconomic burden. Six therapies currently possess a credible evidence base for prevention/suppression of CM. This review is intended to provide an assessment of their relative utility, defined as a blend of safety, tolerability and efficacy, focusing in particular on their safety and tolerability.Areas Covered: We discuss all six medications currently FDA-approved for migraine prevention which also specifically possess credible evidence of efficacy in treating CM. While we do address the efficacy of each, our primary emphasis involves assessment of safety and tolerability data derived from clinical trials and post-marketing experience.Expert Opinion: Recent research involving CM has led to the identification of highly targeted and typically well-tolerated therapies. For patients who experience obstacles to accessing these newer therapies, topiramate is available as an evidence-based alternative, but contraindications, drug-drug interactions and poor tolerability may limit or prevent its use. Although data to support such intervention presently is limited, clinically challenging CM cases may benefit from combination therapy. 'Real world' studies are needed to evaluate such polytherapy, along with studies intended to assess the long-term safety of the individual therapies and their use during pregnancy and breast-feeding.

PEARL study protocol: a real-world study of fremanezumab effectiveness in patients with chronic or episodic migraine

Fremanezumab is a humanized monoclonal antibody (IgG2Δa) that selectively targets calcitonin gene-related peptide and is approved in Europe for migraine prevention in adults with ≥4 migraine days/month. The Pan-European Real Life (PEARL) study is a 24-month, prospective, observational study of fremanezumab in chronic or episodic migraine. End points include proportion of patients with ≥50% reduction in monthly migraine days during 6 months of treatment (primary); changes in monthly migraine days, disability scores and acute headache medication use; adherence and persistence; and effectiveness in patients switching from another calcitonin gene-related peptide pathway-targeting monoclonal antibody. PEARL is being conducted in approximately 100 centers in 11 European countries (estimated n = 1100). PEARL will generate important real-world data on effectiveness of fremanezumab and treatment patterns in patients with chronic migraine or episodic migraine.