Erenumab versus topiramate for the prevention of migraine - a randomised, double-blind, active-controlled phase 4 trial.

BACKGROUND: We compared the tolerability and efficacy of erenumab, a monoclonal antibody binding to the calcitonin gene-related peptide receptor, to topiramate for migraine prophylaxis in adults. METHODS: HER-MES was a 24-week, randomised, double-blind, double-dummy, controlled trial conducted in 82 sites in Germany. Patients with ≥4 migraine days per month and naïve to study drugs were randomly assigned (1:1) to either subcutaneous erenumab (70 or 140 mg/month) plus topiramate placebo (erenumab group) or oral topiramate at the individual dose with optimal efficacy (50-100 mg/day) plus erenumab placebo (topiramate group).The primary endpoint was medication discontinuation due to an adverse event during the double-blind phase. The proportion of patients that achieved ≥50% reduction from baseline in monthly migraine days during the last 3 months of the double-blind phase was a secondary endpoint. RESULTS: Seven hundred and seventy-seven patients were randomised (from 22 February 2019 to 29 July, 2020) and 95.1% completed the study. In the erenumab group, 10.6% discontinued medication due to adverse events compared to 38.9% in the topiramate group (odds ratio, 0.19; 95% confidence interval 0.13-0.27; p < 0.001). Significantly more patients achieved a ≥50% reduction in monthly migraine days from baseline with erenumab (55.4% vs. 31.2%; odds ratio 2.76; 95% confidence interval 2.06-3.71; p < 0.001). No new safety signals occurred. CONCLUSIONS: Erenumab demonstrated a favourable tolerability and efficacy profile compared to topiramate.Trial registration: ClinicalTrials.gov NCT03828539, URL: https://clinicaltrials.gov/ct2/show/NCT03828539.

Erenumab versus topiramate: post hoc efficacy analysis from the HER-MES study.

OBJECTIVE: HER-MES was the first head-to-head, phase 4 trial to assess the tolerability and effectiveness of erenumab against standard of care treatment (topiramate). This post hoc analysis compared the efficacy of erenumab with topiramate in patients who completed the trial on study medication. METHODS: Post hoc sensitivity analysis was performed using the full analysis set. Outcomes assessed included the proportion of patients with a ≥50% reduction in monthly migraine days (MMD) from baseline (50% responder rate), over the last 3 months (months 4, 5, and 6) of the double-blind treatment phase (DBTP), the 50% responder rate during the first month of the DBTP, and change from baseline in MMD during the DBTP. Multiple imputation was done for efficacy values of patients who discontinued study treatment. RESULTS: Patients (N = 777) were randomly assigned (1:1) to either 70 or 140 mg/month erenumab (N = 389) or 50-100 mg/day topiramate (N = 388). Of these, 334 patients (85.9%) receiving erenumab, and 231 patients (59.5%) receiving topiramate completed the DBTP on study medication. Patients on study medication until the end of the DBTP received a mean dose of 119 mg/month for erenumab and 92 mg/day for topiramate. At month 1, a significantly greater proportion of patients receiving erenumab (39.2%) reported ≥50% reduction in MMD from baseline compared with those receiving topiramate (24.0%; p < 0.001). In the last 3 months, a significantly larger proportion of patients receiving erenumab (60.3%) achieved ≥50% reduction in MMD from baseline compared with those receiving topiramate (43.3%; p < 0.001). Patients receiving erenumab demonstrated significantly greater reductions in MMD during the last 3 months from baseline versus those receiving topiramate (- 6.13 vs - 4.90; 95% CI: - 1.87 to - 0.61; p < 0.001). CONCLUSIONS: This post hoc analysis demonstrated significantly superior efficacy of erenumab versus topiramate in achieving a ≥50% reduction in MMD with an early onset of efficacy. TRIAL REGISTRATION: ClinicalTrials.gov NCT03828539 .

Different Munc13 isoforms function as priming factors in lytic granule release from murine cytotoxic T lymphocytes.

In order to fuse lytic granules (LGs) with the plasma membrane at the immunological synapse, cytotoxic T lymphocytes (CTLs) have to render these LGs fusion-competent through the priming process. In secretory tissues such as brain and neuroendocrine glands, this process is mediated by members of the Munc13 protein family. In human CTLs, mutations in the Munc13-4 gene cause a severe loss in killing efficiency, resulting in familial hemophagocytic lymphohistiocytosis type 3, suggesting a similar role of other Munc13 isoforms in the immune system. Here, we investigate the contribution of different Munc13 isoforms to the priming process of murine CTLs at both the mRNA and protein level. We demonstrate that Munc13-1 and Munc13-4 are the only Munc13 isoforms present in mouse CTLs. Both isoforms rescue the drastical secretion defect of CTLs derived from Munc13-4-deficient Jinx mice. Mobility studies using total internal reflection fluorescence microscopy indicate that Munc13-4 and Munc13-1 are responsible for the priming process of LGs. Furthermore, the domains of the Munc13 protein, which is responsible for functional fusion, could be identified. We conclude from these data that both isoforms of the Munc13 family, Munc13-1 and Munc13-4, are functionally redundant in murine CTLs.

A fluorescence resonance energy transfer-based M2 muscarinic receptor sensor reveals rapid kinetics of allosteric modulation.

Allosteric modulators have been identified for several G protein-coupled receptors, most notably muscarinic receptors. To study their mechanism of action, we made use of a recently developed technique to generate fluorescence resonance energy transfer (FRET)-based sensors to monitor G protein-coupled receptor activation. Cyan fluorescent protein was fused to the C terminus of the M(2) muscarinic receptor, and a specific binding sequence for the small fluorescent compound fluorescein arsenical hairpin binder, FlAsH, was inserted into the third intracellular loop; the latter site was labeled in intact cells by incubation with FlAsH. We then measured FRET between the donor cyan fluorescent protein and the acceptor FlAsH in intact cells and monitored its changes in real time. Agonists such as acetylcholine and carbachol induced rapid changes in FRET, indicative of agonist-induced conformational changes. Removal of the agonists or addition of an antagonist caused a reversal of this signal with rate constants between 400 and 1100 ms. The allosteric ligands gallamine and dimethyl-W84 caused no changes in FRET when given alone, but increased FRET when given in the presence of an agonist, compatible with an inactivation of the receptors. The kinetics of these effects were very rapid, with rate constants of 80-100 ms and approximately 200 ms for saturating concentrations of gallamine and dimethyl-W84, respectively. Because these speeds are significantly faster than the responses to antagonists, these data indicate that gallamine and dimethyl-W84 are allosteric ligands and actively induce a conformation of the M(2) receptor with a reduced affinity for its agonists.

Real-world migraine-related healthcare resource utilization and costs associated with improved vs. worsened/stable migraine: a panel-based chart review in France, Germany, Italy, and Spain.

OBJECTIVE: To estimate the migraine-related healthcare resource utilization (HRU) and costs among patients with improved vs. worsened/stable migraine. METHODS: This was a follow-up to a retrospective, panel-based chart review conducted in France, Germany, Italy, and Spain among a panel of physicians (neurologists, headache specialists, and pain specialists) who agreed to participate in patient studies and had treated ≥10 migraine patients in 2017. Eligible physicians extracted data for up to five adults with ≥4 monthly migraine days (MMDs) who initiated a preventive treatment on or after 1 January 2013 and received physician care for ≥6 months after the date of the most recent preventive treatment initiation (index date). Based on the trajectory of migraine severity from the 1-month pre-index period to the 6-month post-index period, cohorts were classified as improved (converting from chronic to episodic or from chronic/episodic to <4 MMDs) or stable/worsened (remaining chronic/episodic or transforming from episodic to chronic) migraine. Migraine-related HRU and costs (2017 €) during the 6-month post-index period were compared between patients with improved vs. stable/worsened migraine. RESULTS: Overall, 470 patient charts were analyzed, with 339 classified as improved migraine and 131 classified as stable/worsened migraine. After adjusting for within-physician correlation, country, sex, and presence of comorbidities before the index date, the improved migraine cohort had significantly fewer migraine-related physician office visits (-0.81; p < .001), emergency room/accident & emergency (ER/A&E) visits (-0.67; p < .001), and hospitalizations (-0.12; p < .001) in the 6-month post-index period vs. the stable/worsened migraine cohort. Consistent with HRU patterns, the adjusted migraine-related costs for physician office visits (-€42.23; p < .05), hospitalizations (-€215.56; p < .05), and total costs (-€396.81; p < .01) in the 6-month post-index period were significantly reduced for the improved migraine cohort vs. the stable/worsened migraine cohort. CONCLUSIONS: Over a 6-month period following initiation of preventive migraine treatment, patients with improved migraine had significantly lower migraine-related HRU and costs than those with stable/worsened migraine.

Real-world healthcare resource utilization related to migraine treatment failure: a panel-based chart review in France, Germany, Italy, and Spain.

Aims: This retrospective chart review examined the six-month migraine-related healthcare resource use (HRU) among European patients who had ≥4 migraine days per month and previously failed at least two prophylactic migraine treatments. Methods: Neurologists, headache specialists, and pain specialists in France, Germany, Italy, and Spain who treated ≥10 patients with migraine in 2017 were recruited (April-June 2018) to extract anonymized patient-level data. Eligible physicians randomly selected charts of up to five adult patients with clinically-confirmed migraine, ≥4 migraine days in the month prior to the index date, and had previously failed at least two prophylactic migraine treatments. Treatment failure was defined as discontinuation due to lack of efficacy and/or tolerability. Demographic and disease characteristics as of the index date, and migraine-related HRU incurred during the 6-month study period, were recorded. Results: A total of 104 physicians contributed 168 charts for patients (63% female). On average, patients were 38 years old and failed 2.3 prophylactic treatments as of the index date. During the study period, 83% of patients had ≥1 outpatient visit for migraine in the physician's office, and 27% went to the ER/A&E. Approximately 5% of patients were hospitalized for migraine, with an average of one hospitalization and an average length of stay of 3 days. Approximately 39% of patients had ≥1 blood test, 22% had ≥1 magnetic resonance imaging, 17% had ≥1 electroencephalogram, and 13% had ≥1 computerized tomography scan. Visits to other healthcare providers were common. Limitations: This study is subject to the limitations of chart review studies, such as errors in data entry. Conclusions: Across four European countries, the HRU burden of migraine among patients who previously failed at least two prophylactic treatments was high, indicating a need for more effective prophylactic treatments to appropriately manage migraine and reduce the HRU burden attributable to this common disorder.

Migraine-related healthcare resource use in the emergency department setting: a panel-based chart review in France, Germany, Italy, and Spain.

Objective: Migraine is a common, disabling condition typically characterized by severe headache, nausea, and/or light and sound sensitivity. This study assessed migraine-related health resource utilization (HRU) occurring in the emergency room/accident & emergency department (ER/A&E) setting among European patients with 4 or more migraine days per month. Methods: Patient-level clinical and HRU data were collected via chart extraction by ER/A&E physicians in France, Germany, Italy, and Spain. Eligible patients had 4 or more migraine days in the month prior to a migraine-related ER/A&E visit and a history of migraine, among other criteria. The index date for each patient was defined as the date of an ER/A&E visit for migraine on or after January 1, 2013. Physician and ER/A&E characteristics, patient and disease characteristics, treatment history, migraine-medication used, and migraine-related HRU (i.e. procedures) during the ER/A&E visit were assessed. Descriptive analyses were conducted in the pooled population, and a sensitivity analysis was performed by country. Results: A total of 467 eligible patient's charts (120 in France, 120 in Germany, 107 in Italy, and 120 in Spain) were provided by 136 physicians (36 in France, 36 in Germany, 28 in Italy, and 36 in Spain). On average, patients spent nearly 8 hours in the ER/A&E. Approximately 82% of patients received a blood test, 62% received an electrocardiography, and 46% received a cranial computerized tomography scan. Despite the majority of patients already using acute or prophylactic treatment upon visiting the ER/A&E, almost all patients were administered or prescribed migraine treatment during the visit. Approximately 21% of patients were admitted to the hospital, and over half of patients were referred to a neurologist or headache specialist. Conclusions: European patients who had four or more migraine days in the month prior to a migraine-related ER/A&E visit had high HRU associated with the visit.

VAMP8-dependent fusion of recycling endosomes with the plasma membrane facilitates T lymphocyte cytotoxicity.

Cytotoxic T lymphocytes (CTLs) eliminate infected and neoplastic cells through directed release of cytotoxic granule contents. Although multiple SNARE proteins have been implicated in cytotoxic granule exocytosis, the role of vesicular SNARE proteins, i.e., vesicle-associated membrane proteins (VAMPs), remains enigmatic. VAMP8 was posited to represent the cytotoxic granule vesicular SNARE protein mediating exocytosis in mice. In primary human CTLs, however, VAMP8 colocalized with Rab11a-positive recycling endosomes. Upon stimulation, these endosomes rapidly trafficked to and fused with the plasma membrane, preceding fusion of cytotoxic granules. Knockdown of VAMP8 blocked both recycling endosome and cytotoxic granule fusion at immune synapses, without affecting activating signaling. Mechanistically, VAMP8-dependent recycling endosomes deposited syntaxin-11 at immune synapses, facilitating assembly of plasma membrane SNARE complexes for cytotoxic granule fusion. Hence, cytotoxic granule exocytosis is a sequential, multivesicle fusion process requiring VAMP8-mediated recycling endosome fusion before cytotoxic granule fusion. Our findings imply that secretory granule exocytosis pathways in other cell types may also be more complex than previously appreciated.