Rates of Response to Atogepant for Migraine Prophylaxis Among Adults: A Secondary Analysis of a Randomized Clinical Trial

The preclinical discovery and development of atogepant for migraine prophylaxis

INTRODUCTION

Atogepant is a selective calcitonin gene-related peptide (CGRP) receptor antagonist that is utilized in adults for the prevention of episodic and chronic migraine. Cumulative findings support the involvement of CGRP in migraine pathophysiology, and atogepant functions by competitively antagonizing CGRP receptors, which results in the inhibition of trigeminovascular nociception. The mechanism of action addresses the cause of migraine pain, providing an effective preventive treatment option.

AREAS COVERED

The key milestones in its development, including preclinical achievements, phase I, II, and III clinical trials, and regulatory approvals are reviewed. Additionally, clinical efficacy, safety profile, and tolerability of atogepant are discussed. The literature review is based on a comprehensive search of English peer-reviewed articles from various electronic databases, including PubMed and ClinicalTrials.gov.

EXPERT OPINION

The development of atogepant represents a significant breakthrough in migraine prevention, particularly due to its improved safety profile that reduces the risk of liver injury, which was a major limitation of first-generation gepants. Drug-drug interaction studies with atogepant highlight the necessity for more inclusive study populations. Given that migraine disproportionately affects females, future clinical development programs should include diverse patient demographics to ensure the findings are generalizable to all individuals suffering from migraine.

Sustained response to atogepant in episodic migraine: post hoc analyses of a 12-week randomized trial and a 52-week long-term safety trial

BACKGROUND

Atogepant is an oral calcitonin gene-related peptide receptor antagonist approved for the preventive treatment of migraine in adults. These analyses evaluated the proportions of clinical trial participants who experienced sustained responses to atogepant over 12 or 52 weeks of treatment.

METHODS

These were post hoc analyses of ADVANCE, a 12-week, double-blind, randomized trial of atogepant 10, 30, and 60 mg once daily vs. placebo for the preventive treatment of episodic migraine, and a separate open-label long-term safety (LTS) trial of atogepant 60 mg once daily over 52 weeks. The 60 mg dose of atogepant was used to detect safety issues. An initial response was defined as ≥50%, ≥75%, or 100% reduction from baseline in MMDs in month 1 for ADVANCE or quarter 1 for the LTS trial. The proportions of participants who continued to experience a response above each response-defining threshold through each subsequent month (for ADVANCE) or each quarter (for LTS) were calculated.

RESULTS

In ADVANCE, sustained response rates during months 2 and 3 varied with dose and were as follows: 70.8-81.1% following an initial ≥50% response, 47.3-61.9% following an initial ≥75% response, and 34.8-41.7% following an initial 100% response. Of those who experienced an initial ≥75% or 100% response during month 1, more than 79% continued to experience at least a 50% response during both months 2 and 3. During the LTS trial, sustained response rates through quarters 2, 3, and 4 were 84.7% following an initial ≥50% response, 72.6% following an initial ≥75% response, and 37.8% following an initial 100% response. Of those who experienced an initial ≥75% or 100% response during quarter 1, more than 90% continued to experience at least a 50% response through quarters 2, 3, and 4.

CONCLUSION

Over 70% of participants who experienced an initial response with atogepant treatment had a sustained response with continued treatment.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT03777059 (submitted: December 13, 2018); NCT03700320 (submitted: September 25, 2018).

Atogepant: Mechanism of action, clinical and translational science

Since the discovery of calcitonin gene-related peptide (CGRP) in 1982, its integral role in migraine pathophysiology, specifically migraine pain, has been demonstrated through cumulative scientific discoveries that have led to the development and approval of migraine-specific therapeutics. Today, eight drugs, including monoclonal antibodies and small molecule CGRP receptor antagonists, known as gepants, have received approval for acute or preventive treatment of migraine. The primary mechanism of these drugs is to block CGRP signaling, thus preventing CGRP-mediated nociception and neurogenic inflammation. Here, we focus on atogepant, a highly potent and selective gepant and the first and only oral medication approved for the preventive treatment of both episodic and chronic migraine in adults. In this article, we summarize the role of CGRP in migraine pathophysiology and the mechanism of action of atogepant. In addition, we provide an overview of atogepant's pharmacology and the key clinical trials and outcomes that have demonstrated the safety and efficacy of atogepant.

The history and rationale of the development of new drugs for migraine treatment

Migraine is one of the most prevalent and disabling diseases in the world. Migraine attack treatments and prophylactic treatments of this disease are essential to lessen its individual, social, and economic impact. This is a narrative review of the main drugs used for treating migraine, as well as the experimental models and the theoretical frameworks that led to their development. Ergot derivatives, triptans, non-steroid anti-inflammatory drugs, tricyclic antidepressants, beta-blockers,: flunarizine,: valproic acid,: topiramate, onabotulinumtoxin A, ditans, monoclonal antibodies against CGRP and its receptor, and gepants are discussed. Possible therapeutic targets for the development of new drugs that are under development are also addressed. Many of the drugs currently in use for treating migraine were developed for the treatment of other diseases, but have proven effective for the treatment of migraine, expanding knowledge about the disease. With a better understanding of the pathophysiology of migraine, new drugs have been and continue to be developed specifically for the treatment of this disease.

Atogepant for the preventive treatment of chronic migraine (PROGRESS): a randomised, double-blind, placebo-controlled, phase 3 trial

BACKGROUND

In this study, we aimed to evaluate the efficacy, safety, and tolerability of atogepant for the preventive treatment of chronic migraine.

METHODS

We did this randomised, double-blind, placebo-controlled, phase 3 trial at 142 clinical research sites across the USA, the UK, Canada, China, Czech Republic, Denmark, France, Germany, Italy, Japan, South Korea, Poland, Russia, Spain, Sweden, and Taiwan. Adults aged 18-80 years with a 1-year or longer history of chronic migraine were randomly assigned (1:1:1) to receive oral atogepant 30 mg twice a day, oral atogepant 60 mg once a day, or placebo. The primary endpoint was change from baseline in mean monthly migraine days (MMDs) across the 12-week treatment period. The primary analysis was done in the modified intent-to-treat population and included all randomly assigned participants who received at least one dose of study intervention, had an evaluable baseline period of electronic diary (eDiary) data, and had at least one evaluable post-baseline 4-week period (weeks 1-4, 5-8, and 9-12) of eDiary data during the double-blind period. The safety population consisted of all participants who received at least one dose of study intervention. This trial is registered with ClinicalTrials.gov (NCT03855137).

FINDINGS

Between March 11, 2019 and Jan 20, 2022, 1489 participants were assessed for eligibility. 711 were excluded, and 778 participants were randomly assigned to atogepant 30 mg twice a day (n=257), atogepant 60 mg once a day (n=262), or placebo (n=259). Participants in the safety population were aged 18-74 years (mean 42·1 years). 459 (59%) of 773 patients were White, 677 (88%) patients were female, and 96 (12%) were male. 84 participants discontinued treatment during the trial, and 755 comprised the modified intent-to-treat population (atogepant 30 mg twice a day n=253, atogepant 60 mg once a day n=256, and placebo n=246). Baseline mean number of MMDs were 18·6 (SE 5·1) with atogepant 30 mg twice a day, 19·2 (5·3) with atogepant 60 mg once a day, and 18·9 (4·8) with placebo. Change from baseline in mean MMDs across 12 weeks was -7·5 (SE 0·4) with atogepant 30 mg twice a day, -6·9 (0·4) with atogepant 60 mg once a day, and -5·1 (0·4) with placebo. Least squares mean difference from placebo was -2·4 with atogepant 30 mg twice a day (95% CI -3·5 to -1·3; adjusted p<0·0001) and -1·8 with atogepant 60 mg once a day (-2·9 to -0·8; adjusted p=0·0009). Most common adverse events for atogepant were constipation (30 mg twice a day 28 [10·9%]; 60 mg once a day 26 [10%]; and placebo 8 [3%]) and nausea (30 mg twice a day 20 [8%]; 60 mg once a day 25 [10%]; and placebo 9 [4%]). Potentially clinically significant weight decrease (≥7% reduction at any time post-baseline) was observed in each treatment group (atogepant 30 mg twice a day 14 [6%]; atogepant 60 mg once a day 15 [6%]; and placebo 5 [2%]).

INTERPRETATION

Atogepant 30 mg twice a day and 60 mg once a day showed clinically relevant reductions in MMDs across 12 weeks in chronic migraine patients. Both atogepant doses were well tolerated, consistent with the known safety profile of atogepant.

FUNDING

Allergan (now AbbVie).

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.

Focus on zavegepant: the first intranasal third-generation gepant

Migraine is the leading cause of years lived with disability in people under 50 and its burden is increased by calcitonin gene-related peptide (CGRP)-driven chronicity. Newly approved small molecules that antagonize the CGRP receptor, gepants, have advanced from the hepatotoxic first-generation telcagepant to third-generation intranasal zavegepant; during this process of drug development, rimegepant, ubrogepant and atogepant, which are orally administered, have been launched and approved for clinical use with no warning for hepatotoxicity. Real-world, long-term postmarketing data about the efficacy and safety of gepants are awaited. The aim of the present drug evaluation study was to provide an overview of the novel, third-generation intranasal Zavegepant, encompassing its development and future perspectives.