OnabotulinumtoxinA in elderly patients with chronic migraine: insights from a real-life European multicenter study

Insights from 25 years of onabotulinumtoxinA in migraine - mechanisms and management

OnabotulinumtoxinA (BTX-A) was first linked to beneficial effects in migraine 25 years ago and was approved by the FDA for preventive treatment of chronic migraine in 2010. The treatment has since had a major impact on the well-being of people with chronic migraine. The clinical development programme for BTX-A and research since its approval have provided insights into the neuromodulatory sensory effect of BTX-A, how it can control chronic migraine despite its peripheral action, and the underlying biology of migraine as a disease. In this Review, we consider the impact that BTX-A has had on the management of chronic migraine and on the research field. We discuss the insights provided by clinical research, encompassing the clinical trials and subsequent real-world evidence, and the mechanistic insights provided by preclinical and translational research. We also provide an overview of future directions of research in the field BTX-A in migraine and the clinical translation of this research.

Real-world effectiveness of Anti-CGRP monoclonal antibodies compared to OnabotulinumtoxinA (RAMO) in chronic migraine: a retrospective, observational, multicenter, cohort study

BACKGROUND

Chronic migraine (CM) is a disabling condition with high prevalence in the general population. Until the recent approval of monoclonal antibodies targeting the calcitonin gene-related peptide (Anti-CGRP mAbs), OnabotulinumtoxinA (BoNT-A) was the only treatment specifically approved for CM prophylaxis. Direct comparisons between the two treatments are not available so far.

METHODS

We performed an observational, retrospective, multicenter study in Italy to compare the real-world effectiveness of Anti-CGRP mAbs and BoNT-A. Patients with CM who had received either treatment according to Italian prescribing regulations were extracted from available clinical databases. Efficacy outcomes included the change from baseline in monthly headache days (MHD), MIgraine Disability ASsessment test (MIDAS), and monthly acute medications (MAM) evaluated at 6 and 12 months of follow-up. The primary outcome was MHD change from baseline at 12 months. Safety outcomes included serious adverse events (SAE) and treatment discontinuation. Unadjusted and adjusted models were used for the analyses.

RESULTS

Two hundred sixteen potentially eligible patients were screened; 183 (86 Anti-CGRP mAbs; 97 BoNT-A) were included. One hundred seventy-one (80 Anti-CGRP mAbs; 91 BoNT-A) and 154 (69 Anti-CGRP mAbs; 85 BoNT-A) patients were included in the efficacy analysis at 6 and 12 months of follow-up, respectively. Anti-CGRP mAbs and BoNT-A both resulted in a mean MHD reduction at 6 (-11.5 and -7.2 days, respectively; unadjusted mean difference -4.3; 95%CI -6.6 to -2.0; p = 0.0003) and 12 months (-11.9 and -7.6, respectively; unadjusted mean difference -4.4; 95%CI -6.8 to -2.0; p = 0.0002) of follow-up. Similar results were observed after adjusting for baseline confounders. Anti-CGRP mAbs showed a significant MIDAS (-31.7 and -19.2 points, p = 0.0001 and p = 0.0296, respectively) and MAM reduction (-5.1 and -3.1 administrations, p = 0.0023 and p = 0.0574, respectively) compared to BoNT-A at 6 and 12 months. No SAEs were reported. One patient receiving fremanezumab discontinued treatment due to arthralgia. Treatment discontinuations, mainly for inefficacy, were comparable.

CONCLUSION

Both Anti-CGRP mAbs and BoNT-A were effective in CM patients with Anti-CGRP mAbs presenting higher effect magnitude, with comparable safety. Still, BoNT-A remains a valuable option for CM patients with contraindications to Anti-CGRP mAbs or for frail categories who are candidates to local therapy with limited risk of systemic administration.

Eptinezumab for the Prevention of Migraine: Clinical Utility, Patient Preferences and Selection - A Narrative Review

The new Calcitonin Gene-Related Peptide (CGRP)-targeted therapies have proven high efficacy and tolerability in episodic and chronic migraine. Eptinezumab is a humanized monoclonal antibody that selectively binds CGRP with high affinity. Eptinezumab was approved by the Food and Drug Administration on February 21st, 2020, for the preventive treatment of migraine in adults. It is administered intravenously over 30 minutes with a standard dose of 100 mg and has a T-max of 30 minutes-1 hour and a half-life of 27 days. These pharmacological properties allow for a very rapid onset of effect and a quarterly administration. It is the first time that a preventive treatment for migraine can be offered as an intravenous administration. As the range of therapeutic possibilities in migraine is expanding, the treatment process must include common decision-making, where physicians should explain in detail to patients the different characteristics of treatment options beyond efficacy and side effects. Patients can now express a preference on a range of opportunities: pharmacological versus non-pharmacological approaches, route of administration, frequency of administration, efficacy, rapidity, side effects, costs, the possibility of titration or dosing, and durability of effectiveness at suspension. Also, patient preferences can be influenced by age, country, migraine severity, and earlier experience with CGRP-targeted therapies. Besides, adherence may be influenced by several factors, including route and the schedule of administration. This narrative review describes a new perspective from the patient's point of view. Clinicians should ally with patients to select treatments that meet each patient's needs and thus apply a tailored approach, addressing not only headaches. In this way, physicians would care for the patients globally and stand out their preferences on different aspects of treatment. Besides, healthcare professionals shall be aware that patients' beliefs about therapies are subject to change with increasing experience with new therapeutic approaches.

Quantitative and Qualitative Pain Evaluation in Response to OnabotulinumtoxinA for Chronic Migraine: An Observational Real-Life Study

(1) Background: Randomized controlled trials and real-life studies demonstrated the efficacy of OnabotulinumtoxinA (OBT-A) for CM prevention. However, no studies specifically addressed its effect on pain's quantitative intensity and qualitative characteristics. (2) Methods: This is an ambispective study: a post-hoc retrospective analysis of real-life prospectively collected data from two Italian headache centers on CM patients treated with OBT-A over one year (i.e., Cy1-4). The primary endpoint was the changes in pain intensity (Numeric Rating Scale, NRS; the Present Pain Intensity (PPI) scale, the 6-point Behavioral Rating Scale (BRS-6)) and quality scale (the short-form McGill Pain Questionnaire (SF-MPQ)) scores. We also assessed the relationship between changes in intensity and quality of pain and disability scale (MIDAS; HIT-6) scores, monthly headache days (MHDs), and monthly acute medication intake (MAMI) (3) Results: We retrieved 152 cases (51.5 years SD 11.3, 80.3% females). From baseline to Cy-4, MHDs, MAMI, NRS, PPI, and BRS-6 scores decreased (consistently p < 0.001). Only the throbbing (p = 0.004), splitting (p = 0.018), and sickening (p = 0.017) qualities of pain collected in the SF-MPQ were reduced. Score variations in MIDAS related to those in PPI scales (p = 0.035), in the BRS-6 (p = 0.001), and in the NRS (p = 0.003). Similarly, HIT-6 score changes related to PPI score modifications (p = 0.027), in BRS-6 (p = 0.001) and NRS (p = 0.006). Conversely, MAMI variation was not associated with qualitative or quantitative pain score modifications except BRS-6 (p = 0.018). (4) Conclusions: Our study shows that OBT-A alleviates migraine by reducing its impact on multiple aspects, such as frequency, disability, and pain intensity. The beneficial effect on pain intensity seems specific to pain characteristics related to C-fiber transmission and is associated with a reduction in migraine-related disability.

New Migraine Drugs for Older Adults

Migraine is one of the most widespread and burdensome diseases, affecting one in every seven individuals in the world, for an estimated global prevalence of 14%. Until recently, therapeutic choices for older migraineurs have been limited by safety concerns and such patients have typically been excluded from clinical trials. However, randomized controlled trials (RCTs) of new migraine drugs have begun to include participants aged over 65 years, offering clinicians relevant safety and efficacy data to be able to treat older patients with the newest drug classes, including monoclonal antibodies for CGRP (r), CGRP antagonists, and drugs targeting the serotonin 5-HT_1F receptor. RCT inclusion criteria nonetheless select the most appropriate older patients, usually excluding polymorbid participants. In a real-life setting, older patients may have several comorbidities, and this reduces the clinical applicability of the new drugs to these patients. Two main points should be addressed to solve this barrier: the inclusion of a sufficient number of migraineurs aged over 65 years in RCTs and the publication of appropriate guidelines for a tailored treatment that considers the existence of multimorbid pathologies in this population of individuals.

OnabotulinumtoxinA: Still the Present for Chronic Migraine

OnabotulinumtoxinA (BT-A) is one of the few drugs approved for the preventive treatment of chronic migraine (CM). Despite this, some aspects of its mechanism of action are still a matter of debate, and the precise magnitude of BT-A effects needs to be completely elucidated. BT-A acts primarily upon trigeminal and cervical nerve endings, by inhibiting the release of inflammatory mediators such as calcitonin gene-related peptide, as well as reducing the insertion of ionotropic and metabotropic receptors into the neuronal membrane. These actions increase the depolarization threshold of trigeminal and cervical nerve fibers, thus reducing their activation. The central actions of BT-A are still a matter of debate: a retrograde axonal transport has been postulated, but not clearly assessed in humans. Clinically, the efficacy of BT-A in CM has been assessed by large, randomized placebo-controlled trials, such as the Phase 3 REsearch Evaluating Migraine Prophylaxis Therapy (PREEMPT) trials. Those results were also confirmed in a wide range of open-label studies, even for long-term periods. Recently, novel findings have led to a better understanding of its pharmacological actions and clinical usefulness in migraine prevention. This narrative review summarizes, updates and critically revises the available data on BT-A and its possible implementation in chronic migraine. Moreover, the current role of BT-A in CM treatment has been discussed.

Real-World Evaluation of the Tolerability to Onabotulinum Toxin A: The RETO Study

Onabotulinumtoxin A (onabotA) has shown efficacy in chronic migraine (CM), with good tolerability and a low rate of adverse effects, most of them not severe. The aim of this study is to evaluate tolerability and adverse effects of onabotA in clinical practice and to analyze if there is a relationship between tolerability to treatment administration, adverse effects' (AEs) occurrence and clinical response. We included patients with CM that received treatment with onabotA for the first time. Tolerability to treatment was evaluated by a 0-10 numeric rating scale (0: worst possible, 10: optimal tolerability). We assessed the presence of AEs by using a standardized questionnaire. Treatment response was based on the 50 and 75% responder rate between weeks 20 and 24, compared with the baseline, according to headache diaries. We analyzed whether the tolerability was associated with a higher frequency of AEs or a higher probability of clinical response. We included 105 patients, 87.7% female, with an age of 43.9 ± 10.7 years. Mean tolerability was 7.8/10 and 7.2/10 in the first and second onabotA administration, respectively. AEs were reported by (first-second) 71.4-68.6% patients. The percentage of patients with a 50% response was 56.3%. There was no association between tolerability and AEs' occurrence or clinical response.