Predictors of response to erenumab after 12 months of treatment

Application of Artificial Intelligence in the Headache Field

PURPOSE OF REVIEW

Headache disorders are highly prevalent worldwide. Rapidly advancing capabilities in artificial intelligence (AI) have expanded headache-related research with the potential to solve unmet needs in the headache field. We provide an overview of AI in headache research in this article.

RECENT FINDINGS

We briefly introduce machine learning models and commonly used evaluation metrics. We then review studies that have utilized AI in the field to advance diagnostic accuracy and classification, predict treatment responses, gather insights from various data sources, and forecast migraine attacks. Furthermore, given the emergence of ChatGPT, a type of large language model (LLM), and the popularity it has gained, we also discuss how LLMs could be used to advance the field. Finally, we discuss the potential pitfalls, bias, and future directions of employing AI in headache medicine. Many recent studies on headache medicine incorporated machine learning, generative AI and LLMs. A comprehensive understanding of potential pitfalls and biases is crucial to using these novel techniques with minimum harm. When used appropriately, AI has the potential to revolutionize headache medicine.

Real-world effectiveness and safety of erenumab for the treatment of migraine: A systematic review and meta-analysis

BACKGROUND

Migraine is a common and disabling primary headache disorder. Several drugs targeting calcitonin gene-related peptide (CGRP), such as erenumab (an anti-CGRP receptor mAb), have been developed recently. However, the real-world effects of erenumab are not well understood.

OBJECTIVE

To assess the clinical effectiveness and safety of erenumab for reducing migraine intensity and frequency in the real world.

METHODS

A systematic search of PubMed, Scopus, Web of Science and the Cochrane Library was conducted from inception to December 2023. Studies estimating the real-world effect of erenumab on monthly migraine days (MMD), monthly headache days (MHD), headache impact test (HIT-6), number of days in medication (NDM), acute monthly intake (AMI), pain intensity (PI) and safety outcomes were included. Meta-analyses of proportions or mean differences were performed.

RESULTS

Fifty-three studies were included. At 3-months, the effect was -7.18 days for MMD, -6.89 days for MHD, -6.97 for HIT-6, -6.22 days for NDM, -15.75 for AMI, and -1.71 for PI. Generally, the effect at 6- and 12-months increased slightly and gradually. The MMD/MHD response rates revealed that approximately one-third of patients exhibited a response greater than 30%, while one-sixth demonstrated a response exceeding 50%. Additionally, 3-4% of patients achieved a response rate of 100%. Adverse event rates were 0.34 and 0.43 at 6- and 12-months, respectively.

CONCLUSION

This study provides strong evidence of the effectiveness and safety of erenumab in the real world; to our knowledge, this is the first real-world meta-analysis specific to erenumab. Erenumab represents a solid therapeutic option for physicians.

Real-World Effectiveness of Calcitonin Gene-Related Peptide-Binding Monoclonal Antibodies for Migraine Prevention: A Systematic Review

Background

Migraine is a neurological disease with a high incidence. The new anti-calcitonin gene-related peptide monoclonal antibodies (anti-CGRP mAbs) have demonstrated effectiveness in preventing episodic and chronic migraine.

Objective

To collect evidence of the real-world effectiveness of anti-CGRP mAbs by assessing outcomes such as reduction in monthly migraine days (MMDs), reduction in monthly headache days (MHDs), and percentage of patients having a 50% reduction in MMDs.

Data Sources

The PubMed database was searched for the period from inception to October 20, 2021.

Study Selection and Data Extraction

Of interest for this review were studies that evaluated the real-world effectiveness of anti-CGRP mAbs in terms of MMDs and reduction in MHDs. The search terms included "migraine", "monthly migraine days", and various drug names. The data are reported in terms of patients' baseline characteristics and treatment effectiveness.

Data Synthesis

A total of 46 studies were evaluated, of which 30 (enrolling a total of 4273 patients across 10 countries) were included in the systematic review. The greatest absolute reduction in MMD was from 20.4 at baseline to 10.7 after 3 months of treatment. After 6 months, the greatest absolute difference was 10, relative to baseline. The largest absolute reduction in MHD at 3 months was from 22 to 8, whereas at 6 months, the greatest absolute reduction in MHD was 13. The treatment could be considered clinically effective (≥ 50% reduction in MMDs) for 41% of patients at 3 months and about 44% of patients at 6 months.

Conclusions

Despite substantial variability in baseline values, this review confirmed the effectiveness of anti-CGRP mAbs, which yielded important clinical reductions in both MMDs and MHDs.

Consensus-Based Recommendations on the Use of CGRP-Based Therapies for Migraine Prevention in the UAE

INTRODUCTION

Migraine is a common debilitating neurological disorder affecting a large proportion of the general population. Calcitonin gene-related peptide (CGRP), a 37-amino acid neuropeptide, plays a key role in the pathophysiology of migraine, and the development of therapies targeting the anti-CGRP pathway has revolutionized the field of migraine treatment.

METHODS

An expert task force of neurologists in the United Arab Emirates (UAE) developed and critically assessed recommendations on the use of CGRP-based therapies in migraine treatment and management in the UAE, based on available published literature. A consensus was reached for each statement by means of an open-voting process, based on a predefined agreement level of at least 60%.

RESULTS

The consensus recommendations advocate the need for guidelines for the appropriate use of CGRP-based therapies by defining patient cohorts and appropriate monitoring of therapeutic response as well as standardizing the initiation, assessment, and cessation of treatment. The consensus recommendations were primarily formulated on the basis of international studies, because of the limited availability of regional and local data. As such, they may also act as guidelines for global healthcare providers.

CONCLUSIONS

These are the first consensus recommendations for the UAE that address the use of CGRP-based therapies in the treatment and management of migraine, integrating both clinical evidence and medical expertise to enhance clinical judgment and decision-making.

Metabolic and toxicological considerations regarding CGRP mAbs and CGRP antagonists to treat migraine in COVID-19 patients: a narrative review

INTRODUCTION

Migraine pharmacological therapies targeting calcitonin gene-related peptide (CGRP), including monoclonal antibodies and gepants, have shown clinical effect and optimal tolerability. Interactions between treatments of COVID-19 and CGRP-related drugs have not been reviewed.

AREAS COVERED

An overview of CGRP, a description of the characteristics of each CGRP-related drug and its response predictors, COVID-19 and its treatment, the interactions between CGRP-related drugs and COVID-19 treatment, COVID-19 and vaccination-induced headache, and the neurological consequences of Covid-19.

EXPERT OPINION

Clinicians should be careful about using gepants for COVID-19 patients, due to the potential drug interactions with drugs metabolized via CYP3A4 cytochrome. In particular, COVID-19 treatment (especially nirmatrelvir packaged with ritonavir, as Paxlovid) should be considered cautiously. It is advisable to stop or adjust the dose (10 mg atogepant when used for episodic migraine) of gepants when using Paxlovid (except for zavegepant). CGRP moncolconal antibodies (CGRP-mAbs) do not have drug - drug interactions, but a few days' interval between a COVID-19 vaccination and the use of CGRP mAbs is recommended to allow the accurate identification of the possible adverse effects, such as injection site reaction. Covid-19- and vaccination-related headache are known to occur. Whether CGRP-related drugs would be of benefit in these circumstances is not yet known.

Real-world evidence of fremanezumab for treating migraine in Japan: a retrospective study

BACKGROUND

There have been very few real-world studies reported in the literature solely focusing on fremanezumab in Asia. This study aimed to evaluate the efficacy and safety of fremanezumab in a real-world setting in Japan.

METHOD

This single-centered, observational, retrospective study examined patients with migraines who received four doses of fremanezumab between December 2021 and August 2022 at Keio University Hospital. We assessed the changes in monthly migraine days, responder rates, and migraine-associated symptoms, as well as injection site reactions and adverse events.

RESULT

Twenty-nine patients were enrolled, wherein 79.3% were women. Compared with those at baseline, the monthly migraine days decreased by 5.9 days at 4 months. The 50% responder rate was 55.2% at 4 months. A total of 57.9%, 47.8%, and 65.0% of patients showed improvement in the severity of photophobia, phonophobia, and nausea/vomiting, respectively. Moreover, injection site reactions were the most common adverse events (55.2%).

CONCLUSION

Fremanezumab is effective and safe for migraine prevention in Japan. Fremanezumab also improved migraine-associated symptoms in half of the patients.

Breaking the cycle: unraveling the diagnostic, pathophysiological and treatment challenges of refractory migraine

Background

Refractory migraine is a poorly described complication of migraine in which migraine has chronified and become resistant to standard treatments. The true prevalence is unknown, but medication resistance is common in headache clinic patient populations. Given the lack of response to treatment, this patient population is extremely difficult to treat with limited guidance in the literature.

Objective

To review the diagnostic, pathophysiological, and management challenges in the refractory migraine population.

Discussion

There are no accepted, or even ICHD-3 appendix, diagnostic criteria for refractory migraine though several proposed criteria exist. Current proposed criteria often have low bars for refractoriness while also not meeting the needs of pediatrics, lower socioeconomic status, and developing nations. Pathophysiology is unknown but can be hypothesized as a persistent "on" state as a progression from chronic migraine with increasing central sensitization, but there may be heterogeneity in the underlying pathophysiology. No guidelines exist for treatment of refractory migraine; once all guideline-based treatments are tried, treatment consists of n-of-1 treatment trials paired with non-pharmacologic management.

Conclusion

Refractory migraine is poorly described diagnostically, its pathophysiology can only be guessed at by extension of chronic migraine, and treatment is more the art than science of medicine. Navigating care of this refractory population will require multidisciplinary care models and an emphasis on future research to answer these unknowns.

Predictors of galcanezumab response in a real-world study of Korean patients with migraine

To assess factors associated with galcanezumab response in a real-world study of Korean patients with migraine. Predictors of the efficacy of monoclonal antibodies targeting calcitonin gene-related peptide (CGRP) or its receptor (anti-CGRP(-R) mAb) have been rarely investigated in Asians. We prospectively recruited and followed up patients with migraine who received monthly galcanezumab treatment in a single university hospital from June 2020 to October 2021. We defined the treatment response with ≥ 50% reduction in moderate/severe headache days in the 3rd month of treatment compared to baseline. Responders and non-responders were compared in terms of demographics, disease characteristics and severity, and previous response to migraine prophylactic treatments. Potential predictors of anti-CGRP(-R) mAb response were tested by using the univariable and multivariable logistic regression analyses. Among 104 patients (81.7% female; mean age 42.0 ± 13.02; 76.9% chronic migraine; and 45.5% medication overuse headache) included, 58 (55.7%) were responders. Non-responders had more chronic migraine, medication overuse headache, monthly headache days, days with acute medication, and daily headaches (i.e. chronic migraine persisting everyday without remission). The multivariable logistic analysis showed chronic migraine (OR 0.05 [95% CI 0.00-0.82], p = 0.036) and the number of previously failed preventive medication classes (OR 0.55 [95% CI 0.33-0.92], p = 0.024] were independently associated with treatment response. Chronic migraine and multiple failures from preventive medication are associated with poor galcanezumab response. Further studies are needed to investigate if earlier treatment before disease chronification or multiple failures may lead to a greater therapeutic gain from anti-CGRP(-R) mAb treatment.

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.

Ten open questions in migraine prophylaxis with monoclonal antibodies blocking the calcitonin-gene related peptide pathway: a narrative review

The monoclonal antibodies (mAbs) blocking the calcitonin-gene related peptide (CGRP) pathway, collectively called here "anti-CGRP/rec mAbs", have dramatically improved preventive migraine treatment. Although their efficacy and tolerability were proven in a number of randomized controlled trials (RCTs) and, maybe even more convincingly, in real world settings, a number of open questions remain. In this narrative review, we will analyze published data allowing insight in some of the uncertainties related to the use of anti-CGRP/rec mAbs in clinical practice: their differential efficacy in migraine subtypes, outcome predictors, switching between molecules, use in children and adolescents, long-term treatment adherence and persistence, effect persistence after discontinuation, combined treatment with botulinum toxin or gepants, added-value and cost effectiveness, effectiveness in other headache types, and potential contraindications based on known physiological effects of CGRP. While recent studies have already provided hints for some of these questions, many of them will not find reliable and definitive answers before larger studies, registries or dedicated RCTs are available.

Impact of anti-CGRP monoclonal antibodies on migraine attack accompanying symptoms: A real-world evidence study

BACKGROUND

Clinical trials on anti-calcitonin gene-related peptide monoclonal antibodies poorly investigated their impact on migraine accompanying symptoms.

OBJECTIVE

To evaluate the impact of basal accompanying symptoms on anti-CGRP monoclonal antibodies treatment response and their evolution after six months of treatment in migraine patients.

METHODS

Patients with migraine diagnosis seen in the Headache Clinic and treated with erenumab, galcanezumab or fremanezumab were prospectively recruited. They completed a daily eDiary which provided data on headache frequency and the following accompanying symptoms of each day: photophobia, phonophobia, nausea, dizziness, and aura. Patients were classified as responders or non-responders based on 50% or greater reduction in headache days per month at month 6 (≥50% response rate). Accompanying symptoms ratios based on headache days per month were assessed per patient at baseline and after three and six months. Comparisons for basal characteristics, basal accompanying symptoms ratios and their evolution after six months between responders and non-responders were performed.

RESULTS

One hundred and fifty-eight patients were included, 44% (69/158) showed ≥50% response rate after six months. A significant reduction in headache days per month in both groups was found at month 6 (-9.4 days/month in ≥50% response rate group; p < 0.001, -2.2 days/month in <50% response rate group; p = 0.004). Additionally, significant decreases in photophobia (-19.5%, p < 0.001), phonophobia (-12.1%, p = 0.010) and aura ratios (-25.1%, p = 0.008) were found in ≥50% response rate group. No statistically significant reductions were found in nausea and dizziness in any group since their reduction was correlated with the decrease in headache days per month. Higher photophobia ratios at baseline were predictive of an increased response between months 3 and 6 (Incidence Risk Ratio = 0.928, p = 0.040).

CONCLUSIONS

The days per month with photophobia, phonophobia and aura decreased at a higher rate than headache days per month after six months in the ≥50% response group. Higher photophobia ratios were associated with higher response rates between three and six months. It could indicate an involvement of peripheral CGRP in photophobia as well as a central modulation of migraine through these treatments which mainly act on the periphery.

A Scoping Review and Meta-Analysis of Anti-CGRP Monoclonal Antibodies: Predicting Response

Calcitonin gene-related peptide-targeted monoclonal antibodies (CGRP mAbs) are increasingly being used as preventive treatments for migraine. Their effectiveness and safety were established through numerous randomized placebo-controlled trials and real-world studies, yet a significant proportion of patients do not respond to this treatment, and currently, there is a lack of accepted predictors of response to guide expectations, as data from studies so far are lacking and inconsistent. We searched Embase and MEDLINE databases for studies reporting on predictors of response to CGRP and/or CGRP-receptor (CGRP-R) mAbs, defined as a 30% or 50% reduction in monthly headache or migraine days at varying durations of follow-up. Quantitative synthesis was performed where applicable. We found 38 real-world studies that investigated the association between various predictors and response rates. Based on these studies, good response to triptans and unilateral pain with or without unilateral autonomic symptoms are predictors of a good response to CGRP(-R) mAbs. Conversely, obesity, interictal allodynia, the presence of daily headaches, a higher number of non-successful previous prophylactic medications, and psychiatric comorbidities including depression are predictive of a poor response to CGRP(-R) mAbs. Future studies should confirm these results and help to generate more tailored treatment strategies in patients with migraine.

The Registry for Migraine (REFORM) study: methodology, demographics, and baseline clinical characteristics

BACKGROUND

Erenumab has demonstrated effectiveness for prevention of migraine attacks, but the treatment is costly, and a considerable proportion of patients do not respond to it. The Registry for Migraine study (REFORM) was initiated to discover biomarkers that can predict response to erenumab in patients with migraine. The specific objective was to investigate differences in erenumab efficacy based on clinical information, blood-based biomarkers, structural and functional magnetic resonance imaging (MRI), and response to intravenous infusion of calcitonin gene-related peptide (CGRP). In this first report of the REFORM study, we provide a comprehensive description of the study methodology, and present the baseline characteristics of the study population.

METHODS

The REFORM study was a single-center, prospective, longitudinal cohort study in adults with migraine who were scheduled to receive preventive treatment with erenumab as part of a separate, open-label, single-arm phase IV trial. The study included four periods: a 2-week screening period (Weeks -6 to -5), 4-week baseline period (Week -4 to Day 1), 24-week treatment period (Day 1 to Week 24), and a 24-week follow-up period without treatment (Week 25 to Week 48). Demographic and clinical characteristics were recorded using a semi-structured interview, whilst outcome data were obtained using a headache diary, patient-reported outcomes, blood sampling, brain MRI, and responsiveness to intravenous infusion of CGRP.

RESULTS

The study enrolled 751 participants, with a mean age ± SD of 43.8 ± 12.2 years, of which 88.8% (n = 667) were female. At enrollment, 64.7% (n = 486) were diagnosed with chronic migraine, and 30.2% (n = 227) had history of aura. The mean monthly migraine days (MMDs) was 14.5 ± 7.0. Concomitant preventive medications were used by 48.5% (n = 364) of the participants, and 39.9% (n = 300) had failed ≥ 4 preventive medications.

CONCLUSION

The REFORM study enrolled a population with a high migraine burden and frequent use of concomitant medications. The baseline characteristics were representative of patients with migraine in specialized headache clinics. Future publications will report the results of the investigations presented in this article.

TRIAL REGISTRATION

The study and sub-studies were registered on ClinicalTrials.gov (NCT04592952; NCT04603976; and NCT04674020).

Galcanezumab for the treatment of chronic migraine and medication overuse headache: Real-world clinical evidence in a severely impaired patient population

BACKGROUND

Galcanezumab is a monoclonal antibody acting against the calcitonin gene-related peptide approved for the preventive treatment of migraine. The aim of this article is to explore its effectiveness and safety of galcanezumab in chronic migraine (CM) with medication overuse-headache (MOH).

METHODS

Seventy-eight patients were consecutively enrolled at the Modena headache center and followed up for 15 months. Visits were scheduled every 3 months, and the following variables were collected: the number of migraine days per month (MDM); the painkillers taken per month (PM); the number of days per month in which the patient took, at least, one painkiller; the six-item headache impact test; and the migraine disability assessment questionnaire (MIDAS) score. Demographic features of the analyzed sample were collected at the baseline and adverse events (AEs) were collected at every visit.

RESULTS

After 12 months, galcanezumab significantly reduced the MDM, the PM, the number of days on medication, the HIT-6 as well as the MIDAS scores (all p < .0001). The greatest amelioration was obtained in the first trimester of treatment. A higher MDM, a higher NRS score at the baseline, and a higher number of failed preventive treatments negatively predict the CM relief at the year of treatment. No serious AEs were registered and only one drop-out was due to AE.

CONCLUSIONS

Galcanezumab is effective and safe for the treatment of patients affected by CM and MOH. Patients with a higher impairment at the baseline may found less benefits with galcanezumab.

Predicting response to CGRP-monoclonal antibodies in patients with migraine in Japan: a single-centre retrospective observational study

BACKGROUND

Anti-calcitonin gene-related peptide monoclonal antibodies (CGRPmAbs) are a favourable option for patients with migraine who experience distressful headache disability and fail to respond to traditional preventive treatment options. However, since CGRPmAb has been available for only 2 years in Japan, the difference between good and poor responders remains unknown. We aimed to investigate the clinical characteristics of patients with migraine in Japan who responded well to CGRPmAb based on real-world data.

METHODS

We analysed patients who visited Keio University Hospital, Tokyo, Japan, between the 12^th of August 2021 and 31^st of August 2022, and were prescribed one of three CGRPmAbs (erenumab, galcanezumab, and fremanezumab) for more than 3 months. We recorded the patients' basic migraine characteristics, such as pain quality, monthly migraine days (MMD)/monthly headache days (MHD), and the number of prior treatment failures. We defined good responders as patients whose MMDs decreased by more than 50% after 3 months of treatment and other patients as poor responders. We compared the baseline migraine characteristics between the two groups and performed logistic regression analysis based on the items that showed statistically significant differences.

RESULTS

In total, 101 patients were considered eligible for the responder analysis (galcanezumab: 57 (56%), fremanezumab: 31 (31%), and erenumab: 13 (13%)). After 3 months of treatment, 55 (54%) patients achieved ≥ 50% reduction in MMDs. Comparisons between ≥ 50% responders and non-responders revealed that age was significantly higher (p = 0.003), and MHD and total prior treatment failures were significantly lower (p = 0.027, 0.040, respectively), in responders than in non-responders. Age was a positive predictive factor, and the total number of prior treatment failures and past medical history of immuno-rheumatologic diseases were negative predictive factors of CGRPmAb responsiveness in Japanese patients with migraine.

CONCLUSIONS

Patients with migraine who are older, with fewer prior treatment failures and no past history of immuno-rheumatologic disease, may respond well to CGRPmAbs.

Monoclonal anti-CGRP antibodies in post-menopausal women: a real-life study

INTRODUCTION

Migraine usually ameliorates after menopause. However, 10-29% of women still experience migraine attacks after menopause, especially if menopause is surgical. The use of monoclonal antibodies against the calcitonin gene-related peptide (CGRP) is changing the landscape of migraine treatment. This study aims to explore the effectiveness and safety of anti-CGRP monoclonal antibodies in women in menopause.

METHODS

Women affected by either migraine or chronic migraine and treated with an anti-CGRP monoclonal antibody for up to 1 year. Visits were scheduled every 3 months.

RESULTS

Women in menopause displayed a similar response compared to women of childbearing age. Among women in menopause, the women experiencing surgical menopause seemed to exhibit a similar response compared to the ones experiencing physiological menopause. Erenumab and galcanezumab displayed similar effectiveness in women in menopause. No serious adverse events were registered.

DISCUSSION

The effectiveness of anti-CGRP monoclonal antibodies is almost the same between women in menopause and women of childbearing age, without appreciable differences between the different antibodies.

Preventive CGRP-targeted therapies for chronic migraine with and without medication-overuse headache

Background:

Calcitonin gene-related peptide (CGRP) targeted therapies are an important breakthrough in migraine prevention. Randomized clinical trials, post-hoc analyses, and phase IV studies have demonstrated their efficacy and safety in chronic migraine patients, including those with concomitant medication-overuse and medication-overuse headache. Real world evidence studies support these findings and provide realistic endpoints for estimation of effect.

Methods and results

We have performed a narrative review including results from double-blind placebo-controlled randomized clinical trials and real-world evidence studies regarding efficacy of the CGRP(-receptor) monoclonal antibodies and CGRP-receptor antagonists (gepants) in patients with chronic migraine with concomitant medication overuse (headache). We have included patient profiles and main efficacy endpoints (monthly migraine days, monthly headache days, monthly acute medication days and percentage responder rates).

Conclusion

The results of this review show that CGRP monoclonal antibodies are effective in chronic migraine patients, also in those with medication overuse (headache). At the time of this review, atogepant clinical trials in chronic migraine have not been communicated. Direct comparative studies are needed for comparison with other treatment options.

An observational study on monoclonal antibodies against calcitonin-gene-related peptide and its receptor

BACKGROUND AND PURPOSE

Based on their pharmacological target, two classes of calcitonin-gene-related peptide (CGRP) monoclonal antibodies (mAbs) have been identified: antibodies against the CGRP ligand-galcanezumab, fremanezumab, eptinezumab-and antibodies against the CGRP receptor (CGRP-R), erenumab. The aim of the present study was to compare anti-CGRP versus anti-CGRP-R mAbs in patients with high frequency episodic and chronic migraine.

METHODS

All patients on monthly treatment with anti-CGRP mAbs with an available 6 months' follow-up at January 2022 were included. Data on efficacy outcome were collected following one (T1), three (T3) and six (T6) months of treatment, and included monthly headache/migraine days, the Migraine Disability Assessment Scale (MIDAS) and Headache Impact Test 6 (HIT-6) scores, pain intensity, analgesics consumption and response rates (>50% headache days reduction compared to baseline).

RESULTS

In all, 152 patients were enrolled, of whom 68 were in treatment with anti-CGRP mAbs (49 galcanezumab, 19 fremanezumab) and 84 with the anti-CGRP-R (erenumab). MIDAS scores were significantly lower in the anti-CGRP group at T1 and T3 (respectively p < 0.02 and p < 0.03) as well as the number of mean migraine days at T3 (p < 0.01). At T3 and T6 outcome measures were comparable, although a significantly higher percentage of super-responders was found in the anti-CGRP group (respectively p < 0.04 and p < 0.05), with a similar overall percentage of responders.

CONCLUSIONS

The present study on a real-world sample confirms the beneficial effect of both anti-CGRP and anti-CGRP-R mAbs, with a more favorable outcome for anti-CGRP antibodies.

Clinical evaluation of super-responders vs. non-responders to CGRP(-receptor) monoclonal antibodies: a real-world experience

BACKGROUND

Clinical trials and real-world studies revealed a spectrum of response to CGRP(-receptor) monoclonal antibodies (mAbs) in migraine prophylaxis, ranging from no effect at all to total migraine freedom. In this study, we aimed to compare clinical characteristics between super-responders (SR) and non-responders (NR) to CGRP(-receptor) mAbs.

METHODS

We performed a retrospective cohort study at the Headache Center, Charité - Universitätsmedizin Berlin. The definition of super-response was a ≥ 75% reduction in monthly headache days (MHD) in the third month after treatment initiation compared to the month prior to treatment begin (baseline). Non-response was defined as ≤ 25% reduction in MHD after three months of treatment with a CGRP-receptor mAb and subsequent three months of treatment with CGRP mAb, or vice versa. We collected demographic data, migraine disease characteristics, migraine symptoms during the attacks in both study groups (SR/NR) as well as the general medical history. SR and NR were compared using Chi-square test for categorical variables, and t-test for continuous variables.

RESULTS

Between November 2018 and June 2022, n = 260 patients with migraine received preventive treatment with CGRP(-receptor) mAbs and provided complete headache documentation for the baseline phase and the third treatment month. Among those, we identified n = 29 SR (11%) and n = 26 NR (10%). SR reported more often especially vomiting (SR n = 12/25, 48% vs. NR n = 4/22, 18%; p = 0.031) and typical migraine characteristics such as unilateral localization, pulsating character, photophobia and nausea. A subjective good response to triptans was significantly higher in SR (n = 26/29, 90%) than in NR (n = 15/25, 60%, p = 0.010). NR suffered more frequently from chronic migraine (NR n = 24/26, 92% vs. SR n = 15/29, 52%; p = 0.001), medication overuse headache (NR n = 14/24, 58% versus SR n = 8/29, 28%; p = 0.024), and concomitant depression (NR n = 17/26, 65% vs. SR n = 8/29, 28%; p = 0.005).

CONCLUSION

Several clinical parameters differ between SR and NR to prophylactic CGRP(-R) mAbs. A thorough clinical evaluation prior to treatment initiation might help to achieve a more personalized management in patients with migraine.

Predictors of response to galcanezumab in patients with chronic migraine: a real-world prospective observational study

BACKGROUND

Despite high efficacy and tolerability, not all patients with chronic migraine benefit from anti-CGRP monoclonal antibodies. We aimed to identify the clinical predictors of the response to galcanezumab treatment in patients with chronic migraine from real-world data.

METHODS

We prospectively recruited patients with CM who underwent galcanezumab injections between December 2019 and February 2022. Treatment response was determined after three months of follow-up and was defined as ≥ 50% reduction in monthly headache days. The migraine characteristics, comorbidities, and other treatment responses were compared between the responder and non-responder groups.

RESULTS

Of 238 patients with CM, 153 (64.3%) showed treatment response. The responder group was younger, had lower frequency of baseline headache days, and had more accompanying symptoms such as nausea, vomiting, and photophobia. Better triptan response and less depression were also observed in the responder group. Multivariable regression analysis revealed that the everyday headache (OR = 0.351, 95% CI = 0.133-0.874, p = 0.017), depression (OR = 0.439, 95% CI = 0.216-0.896, p = 0.024) and absence of accompanying symptoms (OR = 0.314, 95% CI = 0.118-0.834, p = 0.020) were significantly associated with response to galcanezumab treatment.

CONCLUSIONS

Our real-world data showed the efficacy of galcanezumab in patients with CM, regardless of medication overuse. Everyday headache, presence of depression, and absence of accompanying symptoms of migraine were significant predictors of a poor response.

Effectiveness of anti-CGRP monoclonal antibodies in the preventive treatment of migraine: A prospective study of 63 patients

INTRODUCTION

Calcitonine Gen-Related Peptide (CGRP) established a revolution in migraine pathophysiology knowledge and has led to the development of new drugs specifically targeting this disease.

METHODS

We present a prospective study in which 63 episodic and chronic migraine patients have been treated with anti-CGRP monoclonal antibodies describing their efficacy, security and relapses after their interruption. Response predictors have been analyzed such they can help us to create a better treatment plan.

RESULTS

Average age was 48.3 ± 11.81 years old, 84.1% of them being women. The average was of 15.59 migraine days per month (MDM). 63.5% of all patients suffered chronic migraine. The initial dose of Erenumab in all patient was 70 mg subcutaneous. This was increased to 140 mg in 47.6% of the patients. An MDM reduction between 49.85% and 59.53% was obtained within three to twelve months from the start of treatment. Constipation was present in 17.5% of the patients and 4.8% suffered injection site reaction. The treatment was changed to Galcanezumab in 17.9% of the patients. After interrupting the treatment, 23 patients relapsed with a good response on reintroduction of the treatment. It was not possible to establish a clear response predictor, however a statistically significant increase in the number of days of improvement was observed with more MDM at baseline level (p = 0.002).

CONCLUSIONS

Anti-CGRP monoclonal antibodies are effective, safe, and well tolerated drugs. We have observed that their discontinuation, in some cases can lead to frequent and early relapses so we strongly recommend to extend the treatment in those patients with a higher MDM.

Long-Term Safety and Effectiveness of Erenumab in Patients with Migraine: A Systematic Review and Single-Arm Meta-analysis

BACKGROUND AND OBJECTIVE

Several studies on use of erenumab for migraine treatment have been published over recent years. However, its long-term safety and effectiveness have not been consistently established in the literature yet. We aimed to perform a qualitative and quantitative analysis of the long-term safety and effectiveness of erenumab for the treatment of migraine headaches.

METHODS

Long-term follow-up was defined as ≥ 1 year. PubMed, Embase and Cochrane Library were systematically searched from inception to 14 June 2022 for studies meeting the inclusion criteria. Risk of bias was assessed using the Newcastle-Ottawa Scale.

RESULTS

Fourteen studies, comprising 3574 patients, were included. The total follow-up period ranged from 48 to 268 weeks (i.e., 1 year to 5.6 years). Pooled estimate rates for all adverse events (AEs) were 63% (95% CI 46-78); for serious AEs, 3% (95% CI 1-7); and for AEs leading to discontinuation of erenumab, 3% (95% CI 2-5). Reduction in monthly migraine days (MMDs) was -6.98 (95% CI -8.90 to -5.05) and in migraine-specific medication days (MSMDs) was - 6.09 (95% CI - 9.43 to - 2.75). More than half (57%; 95% CI 51-63) and around one-third (35%; 95% CI 28-42) of patients presented with reductions of ≥ 50% and ≥ 75% in MMDs, respectively. Headache Impact Test-6 (HIT-6) score was decreased by -9.68 points (95% CI - 12.03 to - 7.34). Nine studies were considered of poor methodological quality and five of fair quality.

CONCLUSIONS

Erenumab has a favorable safety profile, with a low incidence of serious AEs, and sustained efficacy over ≥1 year of follow-up in the treatment of migraine.

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.

Efficacy of erenumab and factors predicting response after 3 months in treatment resistant chronic migraine: a clinical service evaluation

Background

Calcitonin gene-related peptide (CGRP) inhibitors have been developed as options for treatment of chronic and episodic migraine. We present our experience of the use of erenumab in a tertiary headache centre.

Methods

This was a prospective clinical audit of all patients commenced on erenumab following a locally agreed pathway and criteria over a consecutive period. Patients received monthly erenumab 140 mg for 3 months. Data were collected prospectively at baseline and 3 months follow up.

Results

One hundred three patients were commenced on erenumab during the study period. Patients had tried a median of 7 previous prophylactics, including onabotulinum toxin A in 94%. At 3 months there was a reduction in median total (28 to 20, 29% reduction, p < 0.0001) and severe (15 to 5, 67% reduction, p < 0.0001) headache days. 39.8% of patients achieved at least a 30% reduction in total headache days; 61.8% of patients achieved at least a 50% reduction in severe headache days. Meeting either of these thresholds was considered a positive response, 68% of patients achieved this. Presence of daily headache pattern was negatively associated with response, (56% response vs. 90% without daily headache, p = 0.0003). There was no association between age, gender, presence of medication overuse or number of previously tried prophylactic treatments and response to erenumab. 43% of patients reported at least one adverse effect, most commonly constipation (26%); treatment was discontinued in 3 patients due to adverse effects.

Conclusions

Erenumab was an effective treatment for chronic migraine in this treatment resistant population over 3 months of follow up. Presence of daily headache predicted poorer response but there was still a significant positive response rate in this group.

Does MIDAS reduction at 3 months predict the outcome of erenumab treatment? A real-world, open-label trial

Background

In Italy, monoclonal antibodies targeting the CGRP pathway are subsidized for the preventive treatment of high frequency and chronic migraine (CM) in patients with a MIgraine Disability ASsessment (MIDAS) score ≥ 11. Eligibility to treatment continuation requires a ≥ 50% MIDAS score reduction at three months (T3). In this study, we evaluate whether a ≥ 50% MIDAS score reduction at T3 is a reliable predictor of response to one-year erenumab treatment.

Methods

In this prospective, open-label, real-world study, 77 CM patients were treated with erenumab 70–140 mg s.c. every 28 days for one year (T13). We collected the following variables: monthly migraine days (MMDs), monthly headache days (MHDs), days of acute medication intake, MIDAS, HIT-6, anxiety, depression, quality of life and allodynia. Response to erenumab was evaluated as: i) average reduction in MMDs during the 1-year treatment period; and ii) percentage of patients with ≥ 50% reduction in MMDs during the last 4 weeks after the 13th injection (RespondersT13).

Results

Erenumab induced a sustained reduction in MMDs, MHDs and intake of acute medications across the 12-month treatment period, with 64.9% of patients qualifying as RespondersT13. At T3, 55.8% of patients reported a ≥ 50% reduction in MIDAS score (MIDASRes) and 55.4% of patients reported a ≥ 50% reduction in MMDs (MMDRes). MIDASRes and MMDRes patients showed a more pronounced reduction in MMDs during the 1-year treatment as compared to NON-MIDASRes (MIDASRes: T0: 23.5 ± 4.9 vs. T13: 7.7 ± 6.2; NON- MIDASRes: T0: 21.6 ± 5.4 vs. T13: 11.3 ± 8.8, p = 0.045) and NON-MMDRes (MMDRes: T0: 23.0 ± 4.5 vs. T13: 6.6 ± 4.8; NON-MMDRes: T0: 22.3 ± 6.0 vs. T13: 12.7 ± 9.2, p < 0.001) groups. The percentage of RespondersT13 did not differ between MIDASRes (74.4%) and NON-MIDASRes (52.9%) patients (p = 0.058), while the percentage of RespondersT13 was higher in the MMDRes group (83.3%) when compared to NON-MMDRes (42.9%) (p = 0.001). MMDRes predicted the long-term outcome according to a multivariate analysis (Exp(B) = 7.128; p = 0.001), while MIDASRes did not. Treatment discontinuation based on MIDASRes would have early excluded 36.0% of RespondersT13. Discontinuation based on “either MIDASResor MMDRes” would have excluded a lower percentage (16%) of RespondersT13.

Conclusion

MIDASRes only partly reflects the 12-month outcome of erenumab treatment in CM, as it excludes more than one third of responders. A criterion based on the alternative consideration of ≥ 50% reduction in MIDAS score or MMDs in the first three months of treatment represents a more precise and inclusive option.

Trial registration

The trial was retrospectively registered at www.clinicaltrials.gov (NCT05442008).

Graphical Abstract

CGRP: Calcitonin Gene Related Peptide. MIDAS: MIgraine Disability Assessment. MMDs: monthly migraine days. MIDASRes: Patients with a MIDAS score reduction of at least 50% at T3. MMDRes: Patients with a MMDs reduction of at least 50% at T3. ResponderT13: Patients with a MMDs reduction from baseline of at least 50% in the last 4 weeks of observation period (after 13 erenumab administrations). T0: First erenumab administration. T3, T6, T9, T12: Follow-up visits at three, six, nine, and twelve months after first erenumab administration. T13: Last visit of the protocol.

Machine-learning based approach to predict anti-CGRP response in patients with migraine: multicenter Spanish study

BACKGROUND

To date, several variables have been associated with anti-CGRP receptor or ligand-antibody response with disparate results. Our objective is to determine whether machine learning (ML)-based models can predict 6, 9 and 12 months response to anti-CGRP receptor or ligand therapies among migraine patients.

METHODS

We performed a multicenter analysis of a prospectively collected data cohort of patients with migraine receiving anti-CGRP therapies. Demographic and clinical variables were collected. Response rate defined in the 30% to 50% range -or at least 30%-, in the 50% to 75% range -or at least 50%-, and response rate over 75% reduction in the number of headache days per month at 6, 9 and 12 months. A sequential forward feature selector was used for variable selection and ML-based predictive models response to anti-CGRP therapies at 6, 9 and 12 months, with models' accuracy not less than 70%, were generated.

RESULTS

A total of 712 patients were included, 93% women, aged 48 years (SD=11.7). Eighty-three percent had chronic migraine. ML models using headache days/month, migraine days/month and HIT-6 variables yielded predictions with a F1 score range of 0.70-0.97 and AUC (area under the receiver operating curve) score range of 0.87-0.98. SHAP (SHapley Additive exPlanations) summary plots and dependence plots were generated to evaluate the relevance of the factors associated with the prediction of the above-mentioned response rates.

CONCLUSIONS

According to our study, ML models can predict anti-CGRP response at 6, 9 and 12 months. This study provides a predictive tool to be used in a real-world setting.

European Headache Federation guideline on the use of monoclonal antibodies targeting the calcitonin gene related peptide pathway for migraine prevention - 2022 update

Background

A previous European Headache Federation (EHF) guideline addressed the use of monoclonal antibodies targeting the calcitonin gene-related peptide (CGRP) pathway to prevent migraine. Since then, randomized controlled trials (RCTs) and real-world evidence have expanded the evidence and knowledge for those treatments. Therefore, the EHF panel decided to provide an updated guideline on the use of those treatments.

Methods

The guideline was developed following the Grading of Recommendation, Assessment, Development, and Evaluation (GRADE) approach. The working group identified relevant questions, performed a systematic review and an analysis of the literature, assessed the quality of the available evidence, and wrote recommendations. Where the GRADE approach was not applicable, expert opinion was provided.

Results

We found moderate to high quality of evidence to recommend eptinezumab, erenumab, fremanezumab, and galcanezumab in individuals with episodic and chronic migraine. For several important clinical questions, we found not enough evidence to provide evidence-based recommendations and guidance relied on experts’ opinion. Nevertheless, we provided updated suggestions regarding the long-term management of those treatments and their place with respect to the other migraine preventatives.

Conclusion

Monoclonal antibodies targeting the CGRP pathway are recommended for migraine prevention as they are effective and safe also in the long-term.

Supplementary Information

The online version contains supplementary material available at 10.1186/s10194-022-01431-x.

Migraine Prevention with Erenumab: Focus on Patient Selection, Perspectives and Outcomes

Erenumab is a monoclonal antibody targeting the calcitonin gene-related peptide (CGRP) receptor suitable for episodic and chronic migraine prevention. Randomized clinical trials proved the superiority of erenumab to placebo in a strictly selected population, while real-world studies confirmed treatment efficacy in more severe forms of disease – most patients suffered from chronic migraine with medication overuse headache, had prior treatment failures, and long disease duration. According to guidelines, anti-CGRP pathway monoclonal antibodies should be reserved to patients who failed or have contraindication to several classes of preventive treatments. However, their ease of use, tolerability and efficacy make these monoclonal antibodies ideally suitable for most patients with migraine; cost-effectiveness needs to be considered when looking at expanding current prescription criteria. Also, data from open label extensions of randomized control trials confirmed sustained benefits of prolonged treatment up to 5 consecutive years without significant risk of adverse events. Further studies will provide insights on optimal treatment duration to achieve migraine remission and predictors of treatment response. In the present work, we aimed at reviewing design and results of the main studies on erenumab and discussing treatment use in the current migraine prevention scenario; we also summarized the main ongoing research projects and provided clinical perspectives for the future.

Predictors of clinical response to erenumab in patients with migraine

Background:

Anti-CGRP monoclonal antibodies have emerged as efficacious preventive therapies for some, but not all patients with migraine. It is not yet fully understood what predicts treatment response.

Objective:

To identify factors associated with good or poor response to erenumab, the first available CGRP monoclonal antibody.

Methods:

A chart review of patients with migraine from a large headache center who received at least three 4-weekly doses of erenumab between 2018 and 2020 was conducted. Clinical variables were compared between erenumab responders (defined as ≥30% reduction in monthly headache or migraine days at 3 months) and non-responders via logistic regression analyses.

Results:

Among 90 enrolled patients, 62.2% were erenumab responders and 37.8% non-responders. A significantly larger proportion of non-responders were unemployed (58.8% vs. 28.6%), had complex diagnosis (chronic migraine overlapping another primary or secondary headache) (47.1% vs. 14.3%), higher monthly headache days (30 vs. 25.5) and migraine days (20 vs. 12), a higher frequency of daily headache (76.5% vs. 48.2%), and failed more preventive therapies (5.5 vs. 3). Based on logistic regressions, erenumab responsiveness did not significantly associate with duration of migraine, presence of aura, medication overuse, number of concurrent preventives, response to onabotulinumtoxinA or triptans, or certain comorbidities and substance use.

Conclusions:

This work may help improve selection of patients who may benefit from erenumab, but further prospective research studies are needed.

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.

Predictors of response to erenumab after 12 months of treatment

OBJECTIVE

Erenumab is a monoclonal antibody acting against calcitonin gene-related peptide receptor and approved for the preventive treatment of chronic migraine. The aim of the present study is to identify clinical predictors of good response in patients with chronic migraine and medication overuse-headache.

MATERIAL AND METHODS

This was a retrospective single-center not funded study. Enrolled patients were affected by chronic migraine and medication overuse-headache treated with erenumab monthly, up to 1 year. At 1 year, patients were classified as good responders if they displayed a ≥50% reduction in the number of headache days per months compared to the baseline.

RESULTS

After 1 year, a significant improvement in the number of headache days per months, analgesic consumption, 6-items headache impact test, and migraine disability assessment questionnaire scores were obtained compared to the baseline. Patients who obtained a ≥50% reduction in the number of headache days per month compared to the baseline displayed a longer history of medication overuse-headache, a higher number of painkillers taken per month at the baseline and a higher number of failed preventive treatments in the past.

CONCLUSIONS

Patients with longer medication overuse-headache duration, higher analgesic intake, and a higher number of previous preventive treatment failures may receive less benefit with erenumab.