Comparing the Efficacy and Safety of Galcanezumab Versus Rimegepant for Prevention of Episodic Migraine: Results from a Randomized, Controlled Clinical Trial

INTRODUCTION

There have been no prior trials directly comparing the efficacy of different calcitonin gene-related peptide (CGRP) antagonists for migraine prevention. Reported are the results from the first head-to-head study of two CGRP antagonists, galcanezumab (monoclonal antibody) versus rimegepant (gepant), for the prevention of episodic migraine.

METHODS

In this 3-month, double-blind, double-dummy study, participants were randomized (1:1) to subcutaneous (SC) galcanezumab 120 mg per month (after a 240 mg loading dose) and a placebo oral disintegrating tablet (ODT) every other day (q.o.d.) or to rimegepant 75 mg ODT q.o.d. and a monthly SC placebo. The primary endpoint was the proportion of participants with a ≥ 50% reduction in migraine headache days per month from baseline across the 3-month double-blind treatment period. Key secondary endpoints were overall mean change from baseline in: migraine headache days per month across 3 months and at month 3, 2, and 1; migraine headache days per month with acute migraine medication use; Migraine-Specific Quality of Life Questionnaire Role Function-Restrictive domain score at month 3; and a ≥ 75% and 100% reduction from baseline in migraine headache days per month across 3 months.

RESULTS

Of 580 randomized participants (galcanezumab: 287, rimegepant: 293; mean age: 42 years), 83% were female and 81% Caucasian. Galcanezumab was not superior to rimegepant in achieving a ≥ 50% reduction from baseline in migraine headache days per month (62% versus 61% respectively; P = 0.70). Given the pre-specified multiple testing procedure, key secondary endpoints cannot be considered statistically significant. Overall, treatment-emergent adverse events were reported by 21% of participants, with no significant differences between study intervention groups.

CONCLUSIONS

Galcanezumab was not superior to rimegepant for the primary endpoint; however, both interventions demonstrated efficacy as preventive treatments in participants with episodic migraine. The efficacy and safety profiles observed in galcanezumab-treated participants were consistent with previous studies.

TRIAL REGISTRATION

ClinTrials.gov-NCT05127486 (I5Q-MC-CGBD).

Novel peptide calcitonin gene-related peptide antagonists for migraine therapy

OBJECTIVES

It has previously been shown that the peptide (34Pro,35Phe)CGRP27-37 is a potent calcitonin gene-related peptide, CGRP receptor antagonist, and in this project we aimed to improve the antagonist potency through the structural modification of truncated C-terminal CGRP peptides.

METHODS

Six peptide analogues were synthesized and the anti-CGRP activity confirmed using both in vitro and in vivo studies.

KEY FINDINGS

A 10 amino acid-containing peptide VPTDVGPFAF-NH2 (P006) was identified as a key candidate to take forward for in vivo evaluation, where it was shown to be an effective antagonist after intraperitoneal injection into mice. P006 was formulated as a preparation suitable for nasal administration by spray drying with chitosan to form mucoadhesive microcarriers (9.55 ± 0.91 mm diameter) and a loading of 0.2 mg peptide per 20 mg dose.

CONCLUSIONS

The project has demonstrated the potential of these novel small peptide CGRP antagonists, to undergo future preclinical evaluation as anti-migraine therapeutics.

Nasal spray (Zavegepant) for migraines: a mini-review

Neurological disorders, especially migraines, pose a significant global burden. This has driven the recent innovative research being conducted in the field of anti-migraine therapies, including the discovery of Zavegepant for the treatment of acute migraine attacks. Zavegepant is a novel, first-in-class, intranasally administered calcitonin gene-related peptide (CGRP) receptor antagonist that has recently been approved for use in acute migraine attacks. Recent randomized controlled trials comparing Zavegepant with a placebo have demonstrated favorable results with respect to primary endpoints, as well as a desirable safety profile. The current first-line therapy consists of oral triptans, which are associated with lower efficacy, weaker safety profile, and an unsatisfactory preference rate among patients. Moreover, the intranasal method of administration is a characteristic advantage of Zavegepant, as patients suffering from acute migraine attacks cannot easily ingest oral medication, due to severe nausea and vomiting. In this mini-review, the efficacy and safety of Zavegepant will be compared with those of alternative treatments available for migraines, including oral triptans, intranasal triptans, and other CGRP antagonists currently available in the market. With currently available research, Zavegepant holds superiority over other forms of treatment and can be included in the current treatment guidelines for migraine attacks. However, further research is necessary to effectively assess Zavegepant's long-term efficacy, safety, tolerability, and drug-drug interactions.

Novel Oral CGRP Receptor Antagonist Atogepant in the Prevention of Migraine

Advancements in molecular biology and neuroscience have uncovered calcitonin gene-related peptide (CGRP), a neuropeptide consisting of thirty-seven amino acids that plays a crucial role in migraine pathogenesis. CGRP receptor antagonist or gepant is an oral medication that can impede the nociceptive signaling pathway related to CGRP. Atogepant, the latest CGRP antagonist approved by the Food and Drug Administration (FDA) for prophylaxis of episodic migraine, works by non-competitively blocking CGRP receptors, thereby curtailing neurogenic inflammation and pain sensitization. Numerous trials have demonstrated that atogepant is an effective therapy for migraine prevention, with its extended half-life and minimal risks of cardiovascular or liver toxicity making it the first drug in its class primarily authorized for that purpose. In terms of monthly migraine days, monthly headache days, and acute medication usage days, atogepant demonstrated a statistically significant difference from baseline.  It was well-tolerated with low adverse event rates. The most commonly reported adverse events were constipation and nausea. Atogepant appears to be beneficial for migraine prevention, and it may be more useful in those who do not want to take the medication as an injection or who do not require a lengthy duration of pharmacological impact. In this article, we provide a systematic review of the literature on atogepant and migraine, emphasizing current achievements in this field of study.

Atogepant: an emerging treatment for migraine

INTRODUCTION

Until recently, only nonspecific and not always well-tolerated medications were available for migraine prophylaxis. Currently, specific drugs such as calcitonin gene-related peptide (CGRP) monoclonal antibodies and second-generation gepants are marketed for migraine treatment. Atogepant, an orally active small molecule, is a potent, selective antagonist of the CGRP receptor and is the only gepant authorized exclusively for episodic migraine prophylaxis in adults.

AREAS COVERED

Using literature obtained from PubMed, Scopus, Web of Science, Cochrane, and ClinicalTrials.gov (up to February 13^rd, 2022), the authors summarize and evaluate the available data on atogepant for the prophylaxis of episodic migraine.

EXPERT OPINION

From pivotal trials, the efficacy and tolerability of atogepant in episodic migraine prophylaxis seem comparable to those of CGRP monoclonal antibodies, even if comparative studies have not been conducted. To date, limited information is available on atogepant, including the optimal dose and duration of therapy; hence, it is difficult to establish whether it could be a first-line drug for migraine prophylaxis. Furthermore, it is important to evaluate if atogepant use is associated with the risk of cardiovascular and cerebrovascular events, which could result from potent and persistent blockade of vasodilation by CGRP.

Acute Treatment of Migraine: What has Changed in Pharmacotherapies?

Background

Migraine is the most prevalent neurological disorder and the leading cause of disability in individuals under 50 years of age. Two types of migraine therapies have been defined: acute therapy (abortive or symptomatic treatment), the purpose of which is to interrupt migraine attacks, and preventive treatment (prophylactic treatment), the purpose of which is to reduce the frequency and severity of migraine attacks.

Objective

This paper reviews research advances in new agents for acute therapy of migraine.

Material and Methods

This review provides an overview of emerging new drugs for acute treatment of migraine based on clinical evidence and summarizes the milestones of different stages of clinical development.

Results

Two new formulations of sumatriptan, DFN-11 (3 mg doses of subcutaneous sumatriptan) and DFN-02 (a nasal spray of sumatriptan 10 mg and a permeation-enhancing excipient), have been developed, and both of them showed a fast-onset action with efficacy for acute treatment of migraine with fewer adverse events. New drug discovery programs shifted the focus to the development of ditans, a group of antimigraine drugs targeting 5-HT_1F receptors. Only lasmiditan has progressed to phase III clinical trials and was finally approved by the Food and Drug Administration (FDA) for acute migraine treatment. The other target for acute therapy is CGRP receptor antagonists, namely, gepants. Ubrogepant and rimegepant demonstrated statistically significant efficacy, and both were recently approved by the FDA. These 5-HT_1F receptor agonists and CGRP receptor antagonists did not cause vasoconstriction, offering advantages over the current mainstay of specific acute migraine treatment.

Conclusions

Overall, these new agents have expanded the available acute therapies for migraine treatment and will likely change the strategy with which we treat patients with migraine in the future.

Onset, Maintenance, and Cessation of Effect of Galcanezumab for Prevention of Migraine: A Narrative Review of Three Randomized Placebo-Controlled Trials

Introduction

Galcanezumab, a humanized monoclonal antibody that binds to calcitonin gene-related peptide, is approved for the preventive treatment of migraine in adults. It is self-administered once monthly as a subcutaneous injection. This paper describes the time course of effect of galcanezumab in patients with episodic and chronic migraine.

Methods

Data were based on three double-blind, placebo-controlled, phase 3 studies. Patients (1773 episodic and 1113 chronic) were randomized (2:1:1) to monthly doses of placebo, galcanezumab 120 mg with a 240 mg loading dose, or galcanezumab 240 mg (January 2016–March 2017). Onset of effect was determined using a sequential analysis approach based on earliest time point at which galcanezumab achieved and subsequently maintained statistical superiority to placebo. Maintenance of effect was a comparison of the percentages of galcanezumab- and placebo-treated patients with maintenance of at least 50% response at the individual patient level. Cessation of effect was determined during a 4-month post-treatment period on the basis of change from baseline in monthly migraine headache days.

Results

Galcanezumab led to a lower percentage of patients who had a migraine headache on the first day after injection, provided maintenance of effect throughout the duration of the double-blind treatment period, and gradually lost effect without signs of rebound headache throughout the post-treatment period in most patients with episodic and chronic migraine.

Conclusion

Galcanezumab is a novel preventive therapeutic option for adult patients with migraine that has early onset of action, maintenance of effect, and gradual reduction of effect upon treatment cessation.

Trial Registration

ClinicalTrials.gov: NCT02614183 (EVOLVE-1); NCT02614196 (EVOLVE-2); NCT02614261 (REGAIN).

Supplementary Information

The online version contains supplementary material available at 10.1007/s12325-021-01632-x.

Improvements in pain, medication use and quality of life in onabotulinumtoxinA-resistant chronic migraine patients following erenumab treatment - real world outcomes

Background

The CGRP antagonists offer a novel therapeutic approach in migraine. Their utility in patients with severe forms of chronic migraine is a subject of particular interest. We present outcomes of 9 months of erenumab treatment in a cohort of patients with difficult-to-control chronic migraine, all of whom had prior unsatisfactory response to onabotulinumtoxinA.

Methods

We offered erenumab to 98 patients with a prior unsatisfactory response to onabotulinumtoxinA. Eighty of 98 had trialled greater occipital nerve injections (82%), 32/98 peripheral neurostimulation (33%) and 18/98 intravenous dihydroergotamine (18%). Thirty eight of 98 (39%) met the definition of triptan overuse and 43/98 (44%) analgesic overuse. All patients met the EHF criteria for ‘resistant migraine’. Outcome measures (recorded monthly) included days with headache limiting activities of daily living (“red”), not limiting (“amber”), headache free (“green”), and requiring triptans or other analgesics. Quality of life scores - headache impact test 6 (HIT-6), patient health questionnaire 9 (PHQ-9) and pain disability index (PDI) - were also measured.

Results

Mean number of red days improved by − 6.4 days (SE 0.67, 95%CI − 7.7 to − 5.1, p=0.001) at 3 months; − 6.8 days (SE 0.96, 95%CI − 8.80 to − 4.9, p=0.001) at 6 months and − 6.5 days (SE 0.86, 95%CI − 8.3 to − 4.8, p=0.001) at 9 months. Repeated measures ANOVA confirmed improvements in the number of red (p=0.001), green (p=0.001), triptan (p=0.001) and painkiller days (p=0.001) as well as scores of the HIT-6 (p=0.001), PHQ-9 (p=0.001), and PDI (p=0.001) across the duration of study.

Conclusion

We observed improvements in pain, medication use and quality of life in onabotulinumtoxinA-resistant chronic migraine patients following erenumab treatment.

Supplementary Information

The online version contains supplementary material available at 10.1186/s10194-020-01214-2.

Effect of age on pharmacokinetics, efficacy, and safety of galcanezumab treatment in adult patients with migraine: results from six phase 2 and phase 3 randomized clinical trials

Background

Migraine clinical profile may change with age, making it necessary to verify that migraine treatments are equally safe and effective in older patients. These analyses evaluated the effects of patient age on the pharmacokinetics (PK), efficacy, and safety of galcanezumab for prevention of migraine.

Methods

Analyses included efficacy data from three double-blind phase 3 clinical trials: two 6-month studies in episodic migraine (EVOLVE-1, EVOLVE-2: N = 1773) and one 3-month study in chronic migraine (REGAIN:N = 1113). Patients were randomized 2:1:1 to placebo, galcanezumab 120 mg, or galcanezumab 240 mg. Safety and PK data included additional phase 2 and phase 3 trials for a larger sample size of patients > 60 years (range = 18–65 for all studies). Subgroup analyses assessed efficacy measures, adverse event (AE) occurrence, and cardiovascular measurement changes by patient age group. Galcanezumab PK were evaluated using a population analysis approach, where age was examined as a potential covariate on apparent clearance (CL/F) and apparent volume of distribution (V/F) of galcanezumab.

Results

Numbers of baseline monthly migraine headache days were similar across age groups. There were no statistically significant treatment-by-age group interactions for any efficacy measures, except in episodic migraine studies where older patients appeared to have a larger reduction than younger patients in the number of monthly migraine headache days with acute medication use. Age (18–65) had a minimal effect on CL/F, and no effect on V/F. Galcanezumab-treated patients ≥60 years experienced no clinically meaningful increases in blood pressure and no increased frequency in treatment-emergent AEs, discontinuations due to AEs, serious adverse events (SAEs) overall, or cardiovascular SAEs, compared to age-matched placebo-treated patients.

Conclusions

Age (up to 65 years) does not affect efficacy in migraine prevention and has no clinically meaningful influence on galcanezumab PK to warrant dose adjustment. Furthermore, older galcanezumab-treated patients experienced no increases in frequency of AEs or increases in blood pressure compared with age-matched placebo-treated patients.

Trial registrations

EVOLVE-1 (NCT02614183, registered 23 November 2015), EVOLVE-2 (NCT02614196, 23 November 2015), REGAIN (NCT02614261, 23 November 2015), ART-01 (NCT01625988, 20 June 2012, ), I5Q-MC-CGAB (NCT02163993, 12 June 2014, ), I5Q-MC-CGAJ (NCT02614287, 23 November 2015, ), all retrospectively registered.

Calcitonin-gene related peptide is a potent inducer of oedema in rat orofacial tissue

BACKGROUND AND AIMS

This study aimed to assess the potential of calcitonin-gene related peptide (CGRP), a neuropeptide released from sensory nerves, to induce oedema in orofacial tissue.

EXPERIMENTAL APPROACH

Wistar rats (150-200 g) anesthetized with isoflurane were injected intraorally with CGRP (100 μl; 8-33 pmol) in the right side of the mouth. The contralateral side was injected with the same volume of physiological saline. Increased cheek thickness (in mm), as a measure of oedema formation, was assayed bilaterally with a digital caliper before (T = 0) and up to 24 h following injection of CGRP. Pretreatment with antagonists (CGRP_8-37, 10 nmol; pizotifen, 2 mg/kg) was given by intra-oral or subcutaneous injection, 10 or 30 min, respectively, before the inflammatory stimulus. CGRP and CGRP_8-37 were also injected into the rat hind paw to induce oedema. Data are presented as the mean (±SEM) difference in thickness between the right and the left sides at each time.

RESULTS

Following intra-oral injection, CGRP induced a rapidly developing (5-15 min) and long-lasting (6 h), dose-dependent oedema in the rat cheek, blocked by pre-treatment with CGRP_8-37 or pizotifen. CGRP induced a smaller oedematogenic effect in the rat hind paw also blocked by the CGRP antagonist. CGRP (16 pmol) potentiated the oedema induced by co-injected substance P (3.7 nmol) and contributed to the oedema following intraoral injection of carrageenan (100 μg). Injection of CGRP_8-37 alone induced an early but short-lasting oedema.

CONCLUSION

Local injection of CGRP potently induced oedema in the orofacial tissue of rats which was blocked by a CGRP receptor antagonist. The overall inhibition of carrageenan-induced oedema by CGRP_8-37 suggests that endogenous CGRP contributes to an oedematogenic response in orofacial tissues.

Calcitonin Gene-Related Peptide Antagonists and Therapeutic Antibodies

The calcitonin gene-related peptide (CGRP) receptor is composed of the calcitonin receptor-like receptor (CLR, a class B GPCR) and a single-pass membrane protein known as receptor activity modifying protein type 1 (RAMP1). The levels of the CGRP peptide increase during a migraine attack and infusion of CGRP can provoke a migraine attack. Consequently, there is much interest in inhibiting the actions of CGRP as a way to control migraine. Here we describe the development of small molecule antagonists designed to bind to the CGRP receptor to block its action by preventing binding of the CGRP peptide. We also describe the development of antibody drugs, designed to bind either to the CGRP receptor to block its action, or to bind directly to the CGRP peptide. The field has been very active, with one antibody drug approved and three antibody drugs in phase III clinical trial. Initial programs on the development CGRP antagonists were frustrated by liver toxicity but the current outlook is very promising with five small molecule antagonists in various stages of clinical trial.

Population PK Analyses of Ubrogepant (MK-1602), a CGRP Receptor Antagonist: Enriching In-Clinic Plasma PK Sampling With Outpatient Dried Blood Spot Sampling

Merck & Co., Inc. (Kenilworth, New Jersey) has recently published an integrated strategy for implementation of dried blood spots (DBS) in late-stage trials for population pharmacokinetic (PK) modeling. We applied this strategy for another late-stage clinical program: ubrogepant (MK-1602), a novel oral calcitonin gene-related peptide receptor antagonist for acute treatment of migraine. At the time of implementation, ubrogepant was entering phase 2 development. DBS was implemented to acquire PK information proximal to an acute migraine event to enable exposure-response modeling. The clinical endpoint was a spontaneous event, which generally occurs outside a clinic visit. Thus, an innovative feature of this trial was facilitating DBS in an outpatient setting. In vitro and bioanalytical tests established initial method feasibility and suitability for further evaluations in the clinic. A quantitative relationship was developed between blood and plasma concentrations from concurrently collected samples in a phase 1 (healthy subjects) and phase 2 (target patient population) study using graphical and population PK approaches. This integrated information was presented to the Food and Drug Administration for regulatory input. Following regulatory concurrence, DBS was poised for use in further clinical studies. Population PK modeling was used to dissect sources of variability contributing to DBS collection in the outpatient setting. What has been learned from this program has informed the broader integrated strategy of Merck & Co., Inc. (Kenilworth, NJ) for DBS implementation in clinical trials and research to improve the precision of PK data collected in an outpatient setting.