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

Anti-calcitonin Gene-Related Peptide Monoclonal Antibodies in Migraine: Focus on Clinical Pharmacokinetics

The calcitonin gene-related peptide transmission was the target for recent development of drugs that effectively prevent attacks of both episodic and chronic migraine. The aim of this narrative review was to offer deeper insight into pharmacokinetics of monoclonal antibodies approved for prevention of migraine attacks. For this narrative review, relevant literature was searched for in MEDLINE and Google Scholar databases, covering periods 1966-2023 and 2006-2023, respectively. The ClinicalTrials.gov database was also searched for relevant clinical studies whose results had not been published previously in medical journals, covering the period 2000-2023. The monoclonal antibodies from this group are distributed mainly in the plasma and part of the extracellular space; they are neither metabolized in the liver nor excreted via the kidneys. The elimination of galcanezumab, eptinezumab and fremanezumab takes place only by a non-specific linear process via the reticuloendothelial system in the liver, while erenumab is eliminated by a non-specific process and by a specific, saturable process because of binding to receptors located on the cell membrane. Since the elimination processes do not have a large capacity, the half-life is about 2 weeks for erenumab and about 4 weeks for other monoclonal antibodies. Variability in the pharmacokinetics of these monoclonal antibodies is small in different subpopulations, and body weight is the only parameter to consider when choosing the dose of these drugs.

Switching CGRP(r) MoAbs in migraine: what evidence?

INTRODUCTION

Approximately 50% of patients that receive a CGRP(r) MoAb for the preventative treatment of migraine are expected to discontinue therapy. For patients that discontinue CGRP(r) MoAb therapy, few clinical options are available. One potential option is to switch CGRP(r) MoAbs, however, data concerning the efficacy of this intervention is scarce.

AREAS COVERED

This manuscript aims to summarize all available data concerning the potential efficacy of switching CGRP(r) MoAbs following previous medication discontinuation. Data was sourced by completing a database search for the terms: 'CGRP monoclonal antibody switch OR CGRP monoclonal antibody switching.'

EXPERT OPINION

While data considering the potential efficacy of CGRP(r) switching continues to grow, our expert opinion supports the most recent European Headache Federation statement regarding CGRP(r) MoAb prescribing practices, concluding that there remains insufficient data to determine the efficacy of this intervention. As this topic is of significant clinical importance, we recommend a call-to-action to expand on current data considering the therapeutic options for patients that discontinue CGRP(r) MoAb therapy.

Long-Term Outcome After Discontinuation of CGRP-Targeting Therapy for Migraine

PURPOSE OF REVIEW

Calcitonin gene-related peptide (CGRP)-targeting agents are potential candidates for disease-modifying migraine drugs. However, most studies on CGRP-targeting agents have assessed efficacy outcomes rather than long-term effects after discontinuation. This review aimed to synthesize and scrutinize the latest clinical data on the outcomes after the discontinuation of CGRP-targeting therapy in patients with episodic and chronic migraine, with a particular focus on chronic migraine.

RECENT FINDINGS

Real-world studies involving patients with migraine have reported consistent findings of worsened headache frequency and quality of life after the discontinuation of CGRP monoclonal antibodies (CGRP mAbs). Although many patients maintain improvements for up to 4 months after discontinuation compared to baseline (before starting CGRP mAbs), no studies have evaluated the effects of stopping treatment for > 5 months, which is the five-half-life of CGRP mAbs. Several studies have suggested that patients treated with CGRP receptor mAbs experience more rapid deterioration than those treated with CGRP ligand mAbs after discontinuing CGRP mAbs. The results of real-world studies suggest that for many patients with migraine, the benefits of CGRP mAbs diminish months after discontinuation. Therefore, anti-CGRP therapies may not be considered disease-modifying. However, the comprehensive assessment of the disease-modifying potential of these drugs requires studies with extended treatment and cessation durations.

Retreating migraine patients in the second year with monoclonal antibodies anti-CGRP pathway: the multicenter prospective cohort RE-DO study

BACKGROUND

The outcome of migraine patients retreated with monoclonal antibodies (mAbs) targeting the calcitonin gene-related peptide (anti-CGRP) or its receptor (anti-CGRPr) is not completely known.

METHODS

This multicentric prospective observational cohort study assessed monthly migraine days (MMDs), migraine acute medication intake (MAMI), and HIT-6 at baseline, after 90-112 days (Rev-1), after 84-90 days since Rev-1 (Rev-2) and 30 days after the last injection of anti-CGRP/CGRPr mAbs (Year-end), in the first and the second year after a discontinuation period.

RESULTS

We enrolled 226 patients (79.6% with chronic migraine; 55.3% on erenumab and 44.7% on galcanezumab or fremanezumab). MMDs, MAMI, and HIT-6-did not differ at the respective first and second-year evaluations in the entire cohort, and comparing anti-CGRP with anti-CGRPr Abs. MMDs (18.1 ± 7.8 vs. 3.4 ± 7.8), MAMI (26.7 ± 28.3 vs.17.7 ± 17.2), and HIT-6 scores (63.1 ± 5.9 vs. 67.1 ± 10.3) were lower in the second year than in the pre-treatment baseline (consistently, p < 0.0001). Second-year baseline MMDs were lower in patients on anti-CGRP mAbs (p = 0.001) and with lower pre-treatment baseline MMDs (p ≤ 0.001).

CONCLUSION

Anti-CGRP/CGRPr mAbs are effective in the second as in the first year. The use of anti-CGRP or CGRPr mAbs influenced the second-year baseline MMDs, but their effectiveness did not differ during the two treatment years.

The sense of stopping migraine prophylaxis

INTRODUCTION

Migraine prophylactic therapy has changed over recent years with the development and approval of monoclonal antibodies (mAbs) targeting the calcitonin gene-related peptide (CGRP) pathway. As new therapies emerged, leading headache societies have been providing guidelines on the initiation and escalation of such therapies. However, there is a lack of robust evidence looking at the duration of successful prophylaxis and the effects of therapy discontinuation. In this narrative review we explore both the biological and clinical rationale for prophylactic therapy discontinuation to provide a basis for clinical decision-making.

METHODS

Three different literature search strategies were conducted for this narrative review. These include i) stopping rules in comorbidities of migraine in which overlapping preventives are prescribed, notably depression and epilepsy; ii) stopping rules of oral treatment and botox; iii) stopping rules of antibodies targeting the CGRP (receptor). Keywords were utilized in the following databases: Embase, Medline ALL, Web of Science Core collection, Cochran Central Register of Controlled Trials, and Google Scholar.

DISCUSSION

Reasons to guide decision-making in stopping prophylactic migraine therapies include adverse events, efficacy failure, drug holiday following long-term administration, and patient-specific reasons. Certain guidelines contain both positive and negative stopping rules. Following withdrawal of migraine prophylaxis, migraine burden may return to pre-treatment level, remain unchanged, or lie somewhere in-between. The current suggestion to discontinue CGRP(-receptor) targeted mAbs after 6 to 12 months is based on expert opinion, as opposed to robust scientific evidence. Current guidelines advise the clinician to assess the success of CGRP(-receptor) targeted mAbs after three months. Based on excellent tolerability data and the absence of scientific data, we propose if no other reasons apply, to stop the use of mAbs when the number of migraine days decreases to four or fewer migraine days per month. There is a higher likelihood of developing side effects with oral migraine preventatives, and so we suggest stopping these drugs according to the national guidelines if they are well tolerated.

CONCLUSION

Translational and basic studies are warranted to investigate the long-term effects of a preventive drug after its discontinuation, starting from what is known about the biology of migraine. In addition, observational studies and, eventually, clinical trials focusing on the effect of discontinuation of migraine prophylactic therapies, are essential to substantiate evidence-based recommendations on stopping rules for both oral preventives and CGRP(-receptor) targeted therapies in migraine.

Nutrition and Calcitonin Gene Related Peptide (CGRP) in Migraine

Targeting calcitonin gene-related peptide (CGRP) and its receptor by antibodies and antagonists was a breakthrough in migraine prevention and treatment. However, not all migraine patients respond to CGRP-based therapy and a fraction of those who respond complain of aliments mainly in the gastrointestinal tract. In addition, CGRP and migraine are associated with obesity and metabolic diseases, including diabetes. Therefore, CGRP may play an important role in the functioning of the gut-brain-microflora axis. CGRP secretion may be modulated by dietary compounds associated with the disruption of calcium signaling and upregulation of mitogen-activated kinase phosphatases 1 and 3. CGRP may display anorexigenic properties through induction of anorexigenic neuropeptides, such as cholecystokinin and/or inhibit orexigenic neuropeptides, such as neuropeptide Y and melanin-concentrating hormone CH, resulting in the suppression of food intake, functionally coupled to the activation of the hypothalamic 3',5'-cyclic adenosine monophosphate. The anorexigenic action of CGRP observed in animal studies may reflect its general potential to control appetite/satiety or general food intake. Therefore, dietary nutrients may modulate CGRP, and CGRP may modulate their intake. Therefore, anti-CGRP therapy should consider this mutual dependence to increase the efficacy of the therapy and reduce its unwanted side effects. This narrative review presents information on molecular aspects of the interaction between dietary nutrients and CGRP and their reported and prospective use to improve anti-CGRP therapy in migraine.

The importance of an early onset of migraine prevention: an evidence-based, hypothesis-driven scoping literature review

Recently approved migraine preventive therapies facilitate rapid control of migraine activity, potentially improving patients’ lives and minimizing the societal burden of migraine. This review synthesizes available evidence on rates and timing of early onset of migraine prevention and identifies patient-level outcomes related to early onset prevention. This evidence-based scoping review identified all available clinical trial evidence regarding the early onset of prevention of migraine, under the hypothesis ‘Patients with migraine (episodic or chronic) report additional benefits when receiving an approved migraine preventive treatment that demonstrates an early onset of prevention’. Early onset of prevention was defined as migraine preventive benefits within 30 days post-administration. PubMed, EMBASE, and CINAHL were searched for publications between 1988 and 2020. Overall, 16 publications described 18 studies. All studies were conducted in approved treatments [four anti-calcitonin gene-related peptide (CGRP) monoclonal antibodies and one chemodenervation agent] in patients with episodic/chronic migraine; no publications were identified for traditional oral agents for early migraine prevention. Compared to placebo, erenumab (three studies) reduced weekly migraine days within 1 week; fremanezumab (six studies) increased reports of no headache of at least moderate severity on Day 1 and significantly reduced migraine frequency within 1 week; galcanezumab (three studies) significantly reduced the mean number of patients with migraine beginning Day 1 and each day of the first week; eptinezumab (four studies) significantly reduced migraine attack likelihood on Day 1 by > 50% versus baseline; and onabotulinumtoxinA (two studies) reduced headache and migraine days within 1 week. Four publications described function, disability, and quality of life improvements as early as Week 4; none reported cost–benefit. Anti-CGRP monoclonal antibodies (erenumab, fremanezumab, galcanezumab, and eptinezumab) and a chemodenervation agent (onabotulinumtoxinA) provide clinically relevant benefits during the first treatment week. Literature describing clinically relevant benefits regarding early onset of prevention in patients with migraine is limited.

Alpha-Calcitonin Gene Related Peptide: New Therapeutic Strategies for the Treatment and Prevention of Cardiovascular Disease and Migraine

Alpha-calcitonin gene-related peptide (α-CGRP) is a vasodilator neuropeptide of the calcitonin gene family. Pharmacological and gene knock-out studies have established a significant role of α-CGRP in normal and pathophysiological states, particularly in cardiovascular disease and migraines. α-CGRP knock-out mice with transverse aortic constriction (TAC)-induced pressure-overload heart failure have higher mortality rates and exhibit higher levels of cardiac fibrosis, inflammation, oxidative stress, and cell death compared to the wild-type TAC-mice. However, administration of α-CGRP, either in its native- or modified-form, improves cardiac function at the pathophysiological level, and significantly protects the heart from the adverse effects of heart failure and hypertension. Similar cardioprotective effects of the peptide were demonstrated in pressure-overload heart failure mice when α-CGRP was delivered using an alginate microcapsules-based drug delivery system. In contrast to cardiovascular disease, an elevated level of α-CGRP causes migraine-related headaches, thus the use of α-CGRP antagonists that block the interaction of the peptide to its receptor are beneficial in reducing chronic and episodic migraine headaches. Currently, several α-CGRP antagonists are being used as migraine treatments or in clinical trials for migraine pain management. Overall, agonists and antagonists of α-CGRP are clinically relevant to treat and prevent cardiovascular disease and migraine pain, respectively. This review focuses on the pharmacological and therapeutic significance of α-CGRP-agonists and -antagonists in various diseases, particularly in cardiac diseases and migraine pain.

Deterioration of headache impact and health-related quality of life in migraine patients after cessation of preventive treatment with CGRP(-receptor) antibodies

Background

Migraine preventive treatment with CGRP(−receptor) monoclonal antibodies (mAbs) has a positive effect on patients’ health-related quality of life (HRQoL). The German treatment guidelines recommend discontinuing successful treatment with CGRP(−receptor) mAbs after 6–12 months. We aimed to evaluate headache-specific and generic HRQoL for three months after discontinuation of CGRP(−receptor) mAb treatment.

Methods

We conducted a prospective, longitudinal cohort study, including patients with migraine after 8–12 months of therapy with a CGRP(−R) mAb and before a planned discontinuation attempt. HRQoL was assessed at the time of the last mAbs injection (V1), eight weeks later (V2), and sixteen weeks later (V3). For headache-specific HRQoL, we used the Headache Impact Test-6 (HIT-6). Generic HRQoL was determined with the EuroQol-5-Dimension-5-Level (ED-5D-5L) form, and the Short-Form 12 (SF-12), which comprises a Physical Component Summary (PCS-12) and a Mental Component Summary (MCS-12).

Questionnaires’ total scores were compared across the three observation points using nonparametric procedures.

Results

The study cohort consisted of n = 61 patients (n = 29 treated with the CGRP-receptor mAb erenumab and n = 32 with the CGRP mAbs galcanezumab or fremanezumab). The HIT-6 sum score was 59.69 ± 6.90 at V1 and increased by 3.69 ± 6.21 at V3 (p < 0.001), indicating a greater headache impact on patients’ lives. The mean total EQ-D5-L5 score declined from 0.85 ± 0.17 at V1 by − 0.07 ± 0.18 at V3 (p = 0.013). Both Mental and Physical Component Scores of the SF-12 worsened significantly during treatment discontinuation: The PCS-12 total score decreased by − 4.04 ± 7.90 from V1 to V3 (p = 0.013) and the MCS-12 score by − 2.73 ± 9.04 (p = 0.003). Changes in all questionnaires’ scores but the MCS-12 were already significant in the first month of the drug holiday (V2).

Conclusions

Our results show a significant decline in headache impact and generic HRQoL of migraine patients after treatment discontinuation of a CGRP(−R) mAb. The observed deterioration is above the established minimally clinically important differences for each of the questionnaires and can therefore be considered clinically meaningful. Monitoring HRQoL during a discontinuation attempt could facilitate the decision whether or not to resume preventive treatment with CGRP(−R) mAbs.

Migraine evolution after the cessation of CGRP(-receptor) antibody prophylaxis: a prospective, longitudinal cohort study

BACKGROUND

National and international guidelines recommend stopping migraine prophylaxis with CGRP(-receptor) monoclonal antibodies after 6-12 months of successful therapy. In this study, we aimed to analyze the course of migraine for four months after the cessation of CGRP(-receptor) antibodies use.

METHODS

This longitudinal cohort study included patients with migraine who received a CGRP-(receptor) antibody for ≥8 months before treatment cessation. We analyzed headache data in the four-week period prior to mAb treatment initiation (baseline), in the month before the last mAb injection, in weeks 5-8 and 13-16 after last treatment. Primary endpoint of the study was the change of monthly migraine days from the month before last treatment to weeks 13-16. Secondary endpoints were changes in monthly headache days and monthly days with acute medication use.

RESULTS

A total of 62 patients equally distributed between prophylaxis with the CGRP-receptor antibody erenumab and the CGRP antibodies galcanezumab or fremanezumab participated in the study. Patients reported 8.2 ± 6.6 monthly migraine days in the month before last treatment. Monthly migraine days gradually increased to 10.3 ± 6.8 in weeks 5-8 (p = 0.001) and to 12.5 ± 6.6 in weeks 13-16 (p < 0.001) after drug cessation. Monthly migraine days in weeks 13-16 were not different from baseline values (-0.8 ± 5.4; p > 0.999). Monthly headache days and monthly days with acute medication use showed a similar pattern.

CONCLUSIONS

The cessation of CGRP(-receptor) antibodies migraine prophylaxis was associated with a significant increase of migraine frequency and acute medication intake over time.

A narrative review of the importance of pharmacokinetics and drug-drug interactions of preventive therapies in migraine management

Objective

To review the pharmacokinetics of major classes of migraine preventives and the clinical implications of drug–drug interactions (DDIs) with the use of these therapies in migraine management.

Background

Preventive treatments for migraine are recommended for a large proportion of patients with frequent migraine attacks. These patients often exhibit a number of comorbidities, which may lead to the introduction of multiple concomitant therapies. Potential DDIs must be considered when using polytherapy to avoid increased risk of adverse events (AEs) or inadequate treatment of comorbid conditions.

Methods

A literature search was performed to identify pharmacokinetic properties and potential DDIs of beta‐blockers, antiepileptic drugs, antidepressants, calcium channel blockers, gepants, and monoclonal antibody therapies targeting the calcitonin gene‐related peptide pathway with medications that may be used for comorbid conditions.

Results

Most DDIs occur through alterations in cytochrome P450 isoenzyme activity and may be complicated by genetic polymorphism for metabolic enzymes. Additionally, drug metabolism may be altered by grapefruit juice ingestion and smoking. The use of migraine preventive therapies may exacerbate symptoms of comorbid conditions or increase the risk of AEs associated with comorbid conditions as a result of DDIs.

Conclusions

DDIs are important to consider in patients with migraine who use multiple medications. The development of migraine‐specific evidence‐based preventive treatments allows for tailored clinical management that reduces the risk of DDIs and associated AEs in patients with comorbidities.

Scaling Approaches for Pediatric Dose Selection: The Fremanezumab (AJOVY®) Journey to Select a Phase 3 Dose Using Pharmacokinetic Data from a Phase 1 Study

Fremanezumab, a fully humanized IgG2Δa/kappa monoclonal antibody, selectively targets the calcitonin-gene-related peptide (CGRP) and prevents it from binding to the CGRP receptor. The safety, tolerability, pharmacokinetics (PK), and efficacy of fremanezumab for treating migraines administered as a once monthly 225 mg dose or a once quarterly 675 mg dose have been well characterized in adults. The fremanezumab exposure and body weight relationship supported the use of the approved 225 mg monthly adult dose for pediatric patients weighing ≥45 kg. In the pediatric Phase 3 program, a 120 mg dose for patients weighing <45 kg was determined using the results of an open-label study and a population PK modeling and simulation strategy. A thorough evaluation was conducted to further characterize the population PK of fremanezumab and assess the predictive performance of the adult population PK model when applied to the Phase 1 pediatric data, the predictive performance of alternative pediatric population PK models, and the predictive performance of the selected pediatric population PK model via a noncompartmental-based approach. This latter comparison to noncompartmental results provided additional evidence that the pediatric population PK model predicts the observed data well and supports the 120 mg monthly dose in patients weighing <45 kg.

Dose selection for fremanezumab (AJOVY) phase 3 pediatric migraine studies using pharmacokinetic data from a pediatric phase 1 study and a population pharmacokinetic modeling and simulation approach

BACKGROUND

Potential fremanezumab doses for pediatric patients were evaluated using pharmacokinetic modeling and simulation. An open-label phase 1 pharmacokinetic and safety study was conducted in pediatric patients with migraine. This study's results together with refinement of the adult population pharmacokinetic model were used to determine fremanezumab dose recommendations for phase 3 pediatric studies.

METHODS

Initial application of the adult model suggested that a 75 mg dose in pediatric patients would match exposures determined safe and efficacious in adults; thus, in the phase 1 study, 15 patients, aged 6-11 years and weighing 17-45 kg received a single subcutaneous 75 mg fremanezumab dose. The sparse pharmacokinetic data collected were used to refine the adult model and simulate concentration-time profiles for monthly subcutaneous doses (60 to 225 mg) in a virtual pediatric population.

RESULTS

In the phase 1 pediatric study, the safety profile was similar to that of adults. A two-compartment model with first-order absorption and elimination and body weight effects on clearance and central volume was found to adequately describe the pediatric pharmacokinetic data.

CONCLUSIONS

Using exposure matching to the effective adult fremanezumab dose (225 mg subcutaneous monthly), modeling and simulations predict recommended dose of 120 mg in pediatric patients weighing < 45 kg.Registration: The phase 1 study of this report is registered at EudraCT with the identifier 2018-000734-35.

A Pharmacokinetic Bioequivalence Study of Fremanezumab Administered Subcutaneously Using an Autoinjector and a Prefilled Syringe

Fremanezumab (AJOVY; Teva Pharmaceutical Industries Ltd, Netanya, Israel), approved for the preventive treatment of migraine, is available as a subcutaneous injection either once a month or once every 3 months using an autoinjector or a prefilled syringe. The present study evaluated the pharmacokinetic (PK) bioequivalence of a single subcutaneous injection of fremanezumab 225 mg administered using an autoinjector compared to a prefilled syringe in healthy volunteers. Blood samples for PK and antidrug antibodies were collected before and after dosing. Safety and tolerability assessments included physical examinations, adverse event reporting, laboratory evaluations, and immunogenicity. Following single-dose administration, the mean concentration-time profiles for the 2 treatment groups (autoinjector, n = 106; and prefilled syringe, n = 110) were similar. The point estimates for the back-transformed ratio (autoinjector/prefilled syringe) of geometric least squares means of maximum plasma concentration, area under the plasma concentration-time curve from time 0 to the time of the last measurable drug concentration, and area under the plasma concentration-time curve from time 0 extrapolated to infinity were 1.03, 1.04, and 1.05, respectively, with the 90% confidence intervals entirely contained within bioequivalence margins of 0.8 to 1.25. For both groups, median time to maximum observed concentration was 5 days and mean terminal elimination half-life was approximately 29 days. Treatment-related adverse events were reported by 39 (36%) subjects in the autoinjector group and 26 (24%) in the prefilled syringe group, and the majority were nonserious injection site reactions. The incidence of treatment-emergent antidrug antibody response was low and evenly distributed between the autoinjector (n = 3; 3%) and prefilled syringe (n = 4; 4%) groups. These results indicate that the fremanezumab autoinjector presentation provides an easy-to-use bioequivalent PK profile with a similar safety and tolerability profile to that of the prefilled syringe.

Pharmacokinetics, Pharmacodynamics and Drug-Drug Interactions of New Anti-Migraine Drugs-Lasmiditan, Gepants, and Calcitonin-Gene-Related Peptide (CGRP) Receptor Monoclonal Antibodies

In the last few years, there have been significant advances in migraine management and prevention. Lasmiditan, ubrogepant, rimegepant and monoclonal antibodies (erenumab, fremanezumab, galcanezumab, and eptinezumab) are new drugs that were launched on the US pharmaceutical market; some of them also in Europe. This publication reviews the available worldwide references on the safety of these anti-migraine drugs with a focus on the possible drug–drug (DDI) or drug–food interactions. As is known, bioavailability of a drug and, hence, its pharmacological efficacy depend on its pharmacokinetics and pharmacodynamics, which may be altered by drug interactions. This paper discusses the interactions of gepants and lasmiditan with, i.a., serotonergic drugs, CYP3A4 inhibitors, and inducers or breast cancer resistant protein (BCRP) and P-glycoprotein (P-gp) inhibitors. In the case of monoclonal antibodies, the issue of pharmacodynamic interactions related to the modulation of the immune system functions was addressed. It also focuses on the effect of monoclonal antibodies on expression of class Fc gamma receptors (FcγR).

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.

Fremanezumab: a disease-specific option for the preventive treatment of migraine, including difficult-to-treat migraine

Fremanezumab is a fully humanized monoclonal antibody (IgG2Δa) that targets calcitonin gene-related peptide (CGRP), a key neuropeptide involved in the pathophysiology of migraine. Fremanezumab is approved for quarterly and monthly subcutaneous dosing for the preventive treatment of migraine in adults. The phase 3 clinical development program for fremanezumab aimed to evaluate the efficacy of this preventive treatment across different patient populations, including those with difficult-to-treat migraine. Two pivotal 12-week, phase 3, placebo-controlled studies investigated quarterly and monthly dosing of fremanezumab in participants with chronic migraine (HALO CM) and episodic migraine (HALO EM). The efficacy of fremanezumab was further explored in individuals with difficult-to-treat chronic or episodic migraine in the 12-week FOCUS study, which enrolled participants who had previously experienced an inadequate response to 2-4 pharmacological classes of migraine preventive medications. The long-term efficacy of fremanezumab was assessed in a 12-month long-term study (HALO LTS), which enrolled participants completing the 12-week HALO studies and new participants. Across these studies, treatment with fremanezumab dosed quarterly or monthly provided significant reductions in the frequency of migraine days, headache days of at least moderate severity, and migraine- and headache-related disability compared with placebo. Sustained improvements were seen with long-term fremanezumab treatment. Subgroup analyses of participants with difficult-to-treat migraine (those with comorbid depression, overuse of acute headache medications, and concomitant use of other migraine preventive medications) demonstrated the effectiveness of quarterly or monthly fremanezumab in these populations. Ongoing studies are further exploring the potential benefits of fremanezumab in difficult-to-treat migraine and other headache and pain disorders.

Effect of Fremanezumab Monthly and Quarterly Doses on Efficacy Responses

OBJECTIVE

Exposure-response (E-R) models were developed to provide a description of the time-course of treatment effect for monthly and quarterly dosing regimens of fremanezumab.

BACKGROUND

Fremanezumab is a monoclonal antibody for preventive treatment of episodic migraine (EM) and chronic migraine (CM). In phase 2b and 3 clinical studies of fremanezumab, significant reductions in migraine and headache days and other clinical endpoints were observed for patients with EM and patients with CM. Development of E-R models relating individual-specific measures of drug exposure to clinical endpoints provides a more granular understanding of the expected effects of different doses on therapeutic outcomes by accounting for variability in pharmacokinetic (PK) properties.

METHODS

Data from 2 phase 2b and 2 phase 3 studies of adults with EM or CM were used. Individual exposures were calculated from a population PK model and related to monthly migraine days in EM and moderate-severe (M/S) headache days in CM. Model-based stochastic simulations were performed to compare predicted responses for the various treatment regimens.

RESULTS

The effect of average fremanezumab concentration compared to placebo on the reduction in migraine days and M/S headache days was predicted by the models to be similar for 225 mg monthly and 675 mg once quarterly over time for both EM and CM patients. Both regimens were associated with better response than placebo. A similar percent of EM and CM responders was predicted across the range of observed body weights.

CONCLUSIONS

Exposure-response evaluations showed that both monthly (225 mg) and quarterly (675 mg) fremanezumab dosing regimens were appropriate in achieving clinical benefit in adult patients with EM or CM.

CGRP pathway monoclonal antibodies for cluster headache

INTRODUCTION

The involvement of the calcitonin gene-related peptide (CGRP) pathway in primary headache disorders, especially migraine, had led to recent success in the development of new migraine therapies. The CGRP pathway also plays a role in the pathophysiology of cluster headache, so CGRP pathway monoclonal antibodies have been studied in the prevention of cluster headache attacks.

AREAS COVERED

This review will outline the trials of fremanezumab and galcanezumab, the two CGRP pathway monoclonal antibodies that have undergone trials in cluster headache prevention. This review will highlight key efficacy and safety outcomes from the trials.

EXPERT OPINION

Galcanezumab was shown to be efficacious, reducing the frequency of attacks in episodic cluster headache, while fremanezumab failed its primary endpoint in episodic cluster headache. Both fremanezumab and galcanezumab trials in chronic cluster headache were terminated after futility analysis predicting the failure of both trials to fulfil their primary endpoint. The role of CGRP in cluster headache supports ongoing trials of the remaining CGRP pathway monoclonal antibodies and gepants for preventive and acute treatment. A broad view would include targeting neuropeptides involved in parasympathetic signaling in cluster headache, such as pituitary adenylate cyclase-activating peptide (PACAP); such targets warrant exploration in the search of new 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.