Basic Considerations for the Use of Monoclonal Antibodies in Migraine

Adverse event profile of CGRP monoclonal antibodies: findings from the FDA adverse event reporting database

BACKGROUND

Four CGRP Monoclonal Antibodies (mAbs) have been approved for migraine prophylaxis by the Food and Drug Administration (FDA) since 2018. However, there are concerns about the safety of these four drugs for real-world use.

OBJECTIVE

To compare the adverse event profiles of four CGRP-mAbs with FAERS data.

METHODS

The study was based on records from the FAERS database. Only reports containing one of the active ingredients with CGRP-mAbs were included in this study. Disproportionality analyses including but not limited to reporting odds ratio (ROR) and information components (IC) were conducted to identify drug-AE associations.

RESULTS

In total, 58110 reports were identified for CGRP-mAbs. 80 overlapping signals were disproportionately reported. They affected a range of organs and systems, including the gastrointestinal and cardiovascular systems, skin, and hair. Additionally, the rare cardiovascular adverse events were significantly different among the four CGRP-mAbs.

CONCLUSION

We identified numerous shared underlying signals (overlapping signals) for CGRP-mAbs as suspected drugs in multiple systems and organs. The unlabeled common signals may indicate potential safety issues. In addition, the underlying safety signals varied among the four CGRP-mAbs, particularly in the cardiovascular system, and further studies are needed to confirm these associations and the potential clinical implications.

New drugs targeting calcitonin gene-related peptide for the management of migraines

INTRODUCTION

Significant advances in migraine research have contributed to the development of new drugs for the treatment of migraine. Monoclonal antibodies (mAbs) against Calcitonin Gene-Related Peptide (CGRP) or its receptor and CGRP receptor antagonists (gepants) have been associated with a good safety profile and resulted in an overall efficacy in reducing the number of monthly migraine days both in episodic and chronic forms of migraine.

AREAS COVERED

The results from main investigation studies (phase 2 or 3) of CGRP-targeting drugs (both anti-CGRP mAbs and gepants) are reported in this expert-opinion review.

EXPERT OPINION

The introduction of new drugs targeting CGRP is a significant breakthrough in the migraine field, and represents a new generation of therapeutic agents that are available to manage migraine. The evaluation of efficacy and safety in the long-term follow-up and the development of trials comparing the available drugs could improve the current knowledge. The economic sustainability of these drugs remains to be clarified, and a cost-cutting campaign should be promoted based on the high burden of migraine.

Pharmacokinetics, biodistribution and toxicology of novel cell-penetrating peptides

Cell-penetrating peptides (CPPs) have been used in basic and preclinical research in the past 30 years to facilitate drug delivery into target cells. However, translation toward the clinic has not been successful so far. Here, we studied the pharmacokinetic (PK) and biodistribution profiles of Shuttle cell-penetrating peptides (S-CPP) in rodents, combined or not with an immunoglobulin G (IgG) cargo. We compared two enantiomers of S-CPP that contain both a protein transduction domain and an endosomal escape domain, with previously shown capacity for cytoplasmic delivery. The plasma concentration versus time curve of both radiolabelled S-CPPs required a two-compartment PK analytical model, which showed a fast distribution phase (t1/2α ranging from 1.25 to 3 min) followed by a slower elimination phase (t1/2β ranging from 5 to 15 h) after intravenous injection. Cargo IgG combined to S-CPPs displayed longer elimination half-life, of up to 25 h. The fast decrease in plasma concentration of S-CPPs was associated with an accumulation in target organs assessed at 1 and 5 h post-injection, particularly in the liver. In addition, in situ cerebral perfusion (ISCP) of L-S-CPP yielded a brain uptake coefficient of 7.2 ± 1.1 µl g-1 s-1, consistent with penetration across the blood-brain barrier (BBB), without damaging its integrity in vivo. No sign of peripheral toxicity was detected either by examining hematologic and biochemical blood parameters, or by measuring cytokine levels in plasma. In conclusion, S-CPPs are promising non-toxic transport vectors for improved tissue distribution of drug cargos in vivo.

Advances in CGRP Monoclonal Antibodies as Migraine Therapy: A Narrative Review

Migraine is a potentially disabling disorder, yet it remains underdiagnosed and undertreated. The release of the neuropeptide calcitonin gene-related peptide (CGRP) in the trigemino-cerebrovascular system plays a vital role in the evolution of migraine. It enhances peripheral sensitization by mediating neurogenic inflammation and also influences central sensitization. The majority of the drug classes available for migraine prophylaxis are nonspecific and associated with numerous side effects and drug interactions. Anti-CGRP monoclonal antibodies (mAb) are an innovative therapeutic class that fulfills the need for more efficacious and tolerable preventive therapy. While erenumab is a mAb to the CGRP receptor, eptinezumab, fremanezumab, and galcanezumab bind to the CGRP molecule. They decrease the number of headache days and improve disability. Upper respiratory tract infection, nausea, constipation, pain at the site of injection, and fatigue are the associated side effects. CGRP mAbs are an excellent advancement in translational research and are a promising addition in migraine therapy. This article discusses the recent advances in the development of the CGRP mAbs.

Application of a new biological pathogenetic therapy of migraine in clinical practice: expert consensus of the Russian Headache Research Society

This consensus reviewed the main current issues of clinical application and integration into everyday practice of a new targeted preventive therapy for migraine using monoclonal antibodies (mAbs) to the calcitonin gene related peptide (CGRP) ligand or receptor. These recommendations are based on current scientific and clinical studies and an analysis of the results of several years of clinical use. The main purpose of the consensus is to assist practitioners in prescribing effective prophylactic treatment of migraine using anti-CGRP mAbs and to improve care for patients with various forms of the disease. 

Plaque-Targeted Rapamycin Spherical Nucleic Acids for Synergistic Atherosclerosis Treatment

Atherosclerosis with unstable plaques is the dominant pathological basis of lethal cardio-cerebrovascular diseases, which can cause acute death due to the rupture of plaques. Plaque-targeted drug delivery to achieve promoted treatment remains the main challenge because of the systemic occurrence of atheroma. Herein, a rapamycin (RAP) spherical nucleic acid (SNA) structure, capable of specifically accumulating in plaques for synergistic atherosclerosis treatment is constructed. By designing consecutive phosphorothioate (PS) at 3' terminus of the deoxyribonucleic acid (DNA) strand, multiple hydrophobic RAPs are covalently grafted onto the PS segment to form an amphiphilic drug-grafted DNA (RAP-DNA), which successively self-assembles into micellar SNA (RAP-SNA). Moreover, the phosphodiester-DNA segment constitutes the outer shell of RAP-SNA, enabling further hybridization with functional siRNA (targeting lectin-like oxidized low-density lipoprotein receptor-1, LOX-1) to obtain the drug codelivered SNA (LOX-1/RAP-SNA). With two active ingredients inside, LOX-1/RAP-SNA can not only induce robust autophagy and decrease the evil apoptosis of the pathological macrophages, but also simultaneously prohibit the LOX-1-mediated formation of damageable foam cells, realizing the effect of synergistic therapy. As a result, the LOX-1/RAP-SNA significantly reduces the progression of atheroma and stabilizes the plaques, providing a new strategy for synergistically targeted atherosclerosis treatment.

The Arrival of Anti-CGRP Monoclonal Antibodies in Migraine

Remarkable advancements have been made in the field of migraine pathophysiology and pharmacotherapy over the past decade. Understanding the molecular mechanism of calcitonin gene-related peptide (CGRP) has led to the discovery of a novel class of drugs, CGRP functional blocking monoclonal antibodies (mAbs), for migraine prevention. CGRP is a neuropeptide inherently involved in migraine physiology where its receptors are found dispersed throughout the central and peripheral nervous systems. CGRP-targeted mAbs are effective in the preventive treatment of both chronic and episodic migraine. The advantages of mAbs over oral migraine preventives are numerous. Favorable attributes of the mAbs include high affinity and selectivity for CGRP molecular targets, long-circulating plasma half-lives, and limited risk for nonspecific hepatic and renal toxicity. This pharmacological profile leads to fewer off-target (side) effects and drug-drug interactions rendering mAbs an attractive alternative to traditional small molecule therapies, especially for the preventive treatment of migraine. MAbs display minimal drug interaction thus are excellent for patients prescribed with multiple medications. However, the long-term safety of CGRP blockade is incompletely known, and CGRP mAbs use should be avoided during pregnancy. CGRP mAbs represent a radical shift in preventing chronic and episodic migraine.

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.

Glycoengineering of Therapeutic Antibodies with Small Molecule Inhibitors

Monoclonal antibodies (mAbs) are one of the cornerstones of modern medicine, across an increasing range of therapeutic areas. All therapeutic mAbs are glycoproteins, i.e., their polypeptide chain is decorated with glycans, oligosaccharides of extraordinary structural diversity. The presence, absence, and composition of these glycans can have a profound effect on the pharmacodynamic and pharmacokinetic profile of individual mAbs. Approaches for the glycoengineering of therapeutic mAbs—the manipulation and optimisation of mAb glycan structures—are therefore of great interest from a technological, therapeutic, and regulatory perspective. In this review, we provide a brief introduction to the effects of glycosylation on the biological and pharmacological functions of the five classes of immunoglobulins (IgG, IgE, IgA, IgM and IgD) that form the backbone of all current clinical and experimental mAbs, including an overview of common mAb expression systems. We review selected examples for the use of small molecule inhibitors of glycan biosynthesis for mAb glycoengineering, we discuss the potential advantages and challenges of this approach, and we outline potential future applications. The main aim of the review is to showcase the expanding chemical toolbox that is becoming available for mAb glycoengineering to the biology and biotechnology community.

Galcanezumab: A Review in the Prevention of Migraine and Treatment of Episodic Cluster Headache

Galcanezumab (Emgality^®) is a humanized monoclonal antibody targeting the calcitonin gene-related peptide (CGRP), thereby inhibiting its physiological activity, with CGRP playing a key role in the pathophysiology of migraine and headache disorders. In pivotal phase 3 trials, recommended dosages of subcutaneous galcanezumab once monthly were significantly more effective than placebo as preventive therapy in adults with episodic (EVOLVE-1 and -2; over 6 months) or chronic (REGAIN; over 3 months) migraine (±  aura), including in patients who had failed several prior preventive migraine drugs (CONQUER; over 3 months). The beneficial effects of galcanezumab preventive treatment in reducing the number of monthly migraine headache days (MHDs) and improving health-related quality of life (HR-QOL) were sustained during up to 1 year of treatment. In adults with episodic cluster headache, galcanezumab treatment was associated with a significant reduction in the weekly frequency of cluster headache attacks across weeks 1-3 compared with placebo (primary endpoint), albeit during weeks 4-8, there was a convergence of results between these treatment groups. Although further evidence from the clinical setting is required to determine its long-term safety profile, given its convenient administration regimen, efficacy and short-term tolerability profile, monthly galcanezumab represents an important emerging option for the prevention of episodic and chronic migraine (±  aura) and the treatment of episodic cluster headache.

Double-Binding Botulinum Molecule with Reduced Muscle Paralysis: Evaluation in In Vitro and In Vivo Models of Migraine

With a prevalence of 15%, migraine is the most common neurological disorder and among the most disabling diseases, taking into account years lived with disability. Current oral medications for migraine show variable effects and are frequently associated with intolerable side effects, leading to the dissatisfaction of both patients and doctors. Injectable therapeutics, which include calcitonin gene-related peptide-targeting monoclonal antibodies and botulinum neurotoxin A (BoNT/A), provide a new paradigm for treatment of chronic migraine but are effective only in approximately 50% of subjects. Here, we investigated a novel engineered botulinum molecule with markedly reduced muscle paralyzing properties which could be beneficial for the treatment of migraine. This stapled botulinum molecule with duplicated binding domain-binary toxin-AA (BiTox/AA)-cleaves synaptosomal-associated protein 25 with a similar efficacy to BoNT/A in neurons; however, the paralyzing effect of BiTox/AA was 100 times less when compared to native BoNT/A following muscle injection. The performance of BiTox/AA was evaluated in cellular and animal models of migraine. BiTox/AA inhibited electrical nerve fiber activity in rat meningeal preparations while, in the trigeminovascular model, BiTox/AA raised electrical and mechanical stimulation thresholds in Aδ- and C-fiber nociceptors. In the rat glyceryl trinitrate (GTN) model, BiTox/AA proved effective in inhibiting GTN-induced hyperalgesia in the orofacial formalin test. We conclude that the engineered botulinum molecule provides a useful prototype for designing advanced future therapeutics for an improved efficacy in the treatment of migraine.

Optimal treatment strategy of fremanezumab in migraine prevention: a systematic review with network meta-analysis of randomized clinical trials

Identifying the optimal fremanezumab treatment strategy is crucial in treating patients with migraines. The optimal strategy was investigated by assessing the cumulative 50% reduction rate (50%CRR), cumulative 75% reduction rate (75%CRR), reduction in the number of migraine days, treatment-related adverse events, and serious adverse events in patients treated with fremanezumab 225 mg monthly (225 mg), 675 mg monthly (675 mg), 900 mg monthly (900 mg), a single high dose of 675 mg (S675mg), 675 mg at baseline with 225 mg monthly (675/225 mg), and placebo. Biomedical databases were searched for randomized controlled trials on this topic, and data were individually extracted. Risk ratios and mean differences were used to present the pooled results. The surface under the cumulative ranking curve (SUCRA) was used to determine the effects of the medication strategies of fremanezumab. Five trials (n = 3404) were used to form a six-node network meta-analysis. All fremanezumab medication strategies displayed significantly higher cumulative 50% reduction rates than the placebo. The SUCRA revealed that treatment with 675 mg yielded the highest 50%CRR value (mean rank = 2.5). S675 mg was the only treatment with significantly higher 75%CRR reduction rate than placebo, whereas the SUCRA for 225 mg displayed the highest mean rank (2.2). Moreover, 225 mg (mean rank = 2.2) and S675 mg (mean rank = 2.2) presented lower probabilities of serious adverse events. Collectively, S675mg and 225 mg exhibited the optimal balance between efficacy and safety within three months. Long-term efficacy and safety remain unclear, and future studies should further evaluate the long-term outcomes.

Calcitonin gene-related peptide (CGRP)-targeted therapies as preventive and acute treatments for migraine-The monoclonal antibodies and gepants

Calcitonin Gene-Related Peptide (CGRP) plays a pivotal role in migraine pathophysiology. Two types of CGRP function-blocking modalities, monoclonal antibodies, and small molecules (gepants), have been developed to target the CGRP ligands and CGRP receptors. Four CGRP monoclonal antibodies have received FDA approval for the prevention of migraine: erenumab, fremanezumab, galcanezumab, and eptinezumab. Two gepants have been approved by the FDA for the acute treatment of migraine: ubrogepant and rimegepant. Multiple clinical trials of the CGRP monoclonal antibodies and gepants, and now some open-label long-term extension data, established their efficacy, safety, and tolerability. In this chapter, we summarize the major clinical trials, pharmacokinetic insights, safety and tolerability profiles, and real-world data (if available) of the CGRP monoclonal antibodies and gepants.

Medications Approved for Preventing Migraine Headaches

Migraine is the third-most prevalent disease in the world and affects approximately 39 million individuals in the United States alone. Migraine occurs in nearly 1 in 7 individuals between 15 and 49 years of age and is 3 times more frequent in women than in men. The Food and Drug Administration (FDA) recently approved 3 new humanized monoclonal antibodies that target calcitonin gene-related peptide (CGRP): erenumab, fremanezumab, and galcanezumab. The agents either bind to the CGRP receptor (erenumab) or bind to the CGRP ligand (fremanezumab and galcanezumab) and block its binding to the receptor. All 3 products are indicated for preventative treatment of episodic or chronic migraine in adults. The available studies to date document that these agents reduce migraine attacks. The CGRP monoclonal antibodies offer patients new options once they have exhausted other treatments.

Population pharmacokinetic modelling and simulation of fremanezumab in healthy subjects and patients with migraine

Aims

Fremanezumab is a fully humanized IgG₂Δa/κ monoclonal antibody specific for calcitonin gene‐related peptide developed and approved for the preventive treatment of migraine in adults. The population pharmacokinetics (PK) of fremanezumab were characterized in healthy subjects and patients with chronic migraine and episodic migraine, including the effects of intrinsic and extrinsic factors on PK variability.

Methods

Nonlinear mixed effects modelling was performed using NONMEM with data from 7 phase 1–3 clinical trials evaluating selected intravenous and subcutaneous dose regimens. The influence of covariates on fremanezumab PK was assessed and model evaluation was performed through visual predictive checks.

Results

A 2‐compartment model with first‐order absorption and elimination described the PK data well. Typical values for fremanezumab central clearance (0.0902 L/d) and central distribution volume (1.88 L) for a 71‐kg subject were consistent with previously reported values for IgG antibodies. Higher body weight was associated with increased central clearance and distribution volume. Effects of other covariates (age, albumin, renal function, sex, race, injection site, and acute, analgesic and preventive medication use for migraine) were not found to statistically significantly influence fremanezumab PK. There was no indication of reduced exposure in participants with positive anti‐drug antibody status or with mild to moderate hepatic impairment. Absolute bioavailability was estimated at 0.658.

Conclusions

A comprehensive population PK model was developed for fremanezumab following intravenous and subcutaneous administration in healthy subjects and patients with chronic migraine or episodic migraine, which will be used to further evaluate exposure–response relationships for efficacy and safety endpoints.

The pharmacology and therapeutic applications of monoclonal antibodies

Monoclonal antibodies (mAbs) have emerged as a major class of therapeutic agents on the market. To date, approximately 80 mAbs have been granted marketing approval. In 2018, 12 new mAbs were approved by the FDA, representing 20% of the total number of approved drugs. The majority of mAb therapeutics are for oncological and immunological/infectious diseases, but these are expanding into other disease areas. Over 100 monoclonal antibodies are in development, and their unique features ensure that these will remain a part of the therapeutic pipeline. Thus, the therapeutic value and the elucidation of their pharmacological properties supporting clinical development of these large molecules are unquestioned. However, their utilization as pharmacological tools in academic laboratories has lagged behind their small molecule counterparts. Early therapeutic mAbs targeted soluble cytokines, but now that mAbs also target membrane-bound receptors and have increased circulating half-life, their pharmacology is more complex. The principles of pharmacology have enabled the development of high affinity, potent and selective small molecule therapeutics with reduced off-target effects and drug-drug interactions. This review will discuss how the same basic principles can be applied to mAbs, with some important differences. Monoclonal antibodies have several benefits, such as fewer off-target adverse effects, fewer drug-drug interactions, higher specificity, and potentially increased efficacy through targeted therapy. Modifications to decrease the immunogenicity and increase the efficacy are described, with examples of optimizing their pharmacokinetic properties and enabling oral bioavailability. Increased awareness of these advances may help to increase their use in exploratory research and further understand and characterize their pharmacological properties.

The effect of orofacial complete Freund's adjuvant treatment on the expression of migraine-related molecules

Background

Migraine is a neurovascular primary headache disorder, which causes significant socioeconomic problems worldwide. The pathomechanism of disease is enigmatic, but activation of the trigeminovascular system (TS) appears to be essential during the attack. Migraine research of recent years has focused on neuropeptides, such as calcitonin gene-related peptide (CGRP) and pituitary adenylate cyclase-activating polypeptide 1–38 (PACAP1–38) as potential pathogenic factors and possible therapeutic offensives. The goal of present study was to investigate the simultaneous expression of CGRP and precursor of PACAP1–38 (preproPACAP) in the central region of the TS in a time-dependent manner following TS activation in rats.

Methods

The right whisker pad of rats was injected with 50 μl Complete Freund’s Adjuvant (CFA) or saline. A mechanical allodynia test was performed with von Frey filaments before and after treatment. Transcardial perfusion of the animals was initiated 24, 48, 72 and 120 h after injection, followed by the dissection of the nucleus trigeminus caudalis (TNC). After preparation, the samples were stored at − 80 °C until further use. The relative optical density of CGRP and preproPACAP was analyzed by Western blot. One-way ANOVA and Kruskal-Wallis followed by Tukey post hoc test were used to evaluate the data. Regression analysis was applied to explore the correlation between neuropeptides expression and hyperalgesia.

Results

Orofacial CFA injection resulted in significant CGRP and preproPACAP release in the TNC 24, 48, 72 and 120 h after the treatment. The level of neuropeptides reached its maximum at 72 h after CFA injection, corresponding to the peak of facial allodynia. Negative, linear correlation was detected between the expression level of neuropeptides and value of mechanonociceptive threshold.

Conclusion

This is the first study which suggests that the expression of CGRP and preproPACAP simultaneously increases in the central region of activated TS and it influences the formation of mechanical hyperalgesia. Our results contribute to a better understanding of migraine pathogenesis and thereby to the development of more effective therapeutic approaches.

Pharmacologic Characterization of ALD1910, a Potent Humanized Monoclonal Antibody against the Pituitary Adenylate Cyclase-Activating Peptide

Migraine is a debilitating disease that affects almost 15% of the population worldwide and is the first cause of disability in people under 50 years of age, yet its etiology and pathophysiology remain incompletely understood. Recently, small molecules and therapeutic antibodies that block the calcitonin gene-related peptide (CGRP) signaling pathway have reduced migraine occurrence and aborted acute attacks of migraine in clinical trials and provided prevention in patients with episodic and chronic migraine. Heterogeneity is present within each diagnosis and patient's response to treatment, suggesting migraine as a final common pathway potentially activated by multiple mechanisms, e.g., not all migraine attacks respond to or are prevented by anti-CGRP pharmacological interventions. Consequently, other unique mechanisms central to migraine pathogenesis may present new targets for drug development. Pituitary adenylate cyclase-activating peptide (PACAP) is an attractive novel target for treatment of migraines. We generated a specific, high-affinity, neutralizing monoclonal antibody (ALD1910) with reactivity to both PACAP38 and PACAP27. In vitro, ALD1910 effectively antagonizes PACAP38 signaling through the pituitary adenylate cyclase-activating peptide type I receptor, vasoactive intestinal peptide receptor 1, and vasoactive intestinal peptide receptor 2. ALD1910 recognizes a nonlinear epitope within PACAP and blocks its binding to the cell surface. To test ALD1910 antagonistic properties directed against endogenous PACAP, we developed an umbellulone-induced rat model of neurogenic vasodilation and parasympathetic lacrimation. In vivo, this model demonstrates that the antagonistic activity of ALD1910 is dose-dependent, retaining efficacy at doses as low as 0.3 mg/kg. These results indicate that ALD1910 represents a potential therapeutic antibody to address PACAP-mediated migraine.