Sharon Zhou

Psychiatric and behavioral adverse events in randomized clinical studies of the noncompetitive AMPA receptor antagonist perampanel

Perampanel, a selective, noncompetitive α‐amino‐3‐hydroxy‐5‐methyl‐4‐isoxazolepropionic acid (AMPA) glutamate receptor antagonist, is indicated for adjunctive treatment of partial seizures in patients ≥12 years based on three phase III clinical studies. The perampanel U.S. Prescribing Information includes a boxed warning for serious psychiatric and behavioral adverse reactions. To provide context for this warning, detail on psychiatric and behavioral safety data from perampanel clinical studies is presented.

Efficacy and safety of perampanel in the subgroup of elderly patients included in the phase III epilepsy clinical trials

Clinical data regarding use of antiepileptic drugs in the elderly are generally scarce. Therefore, a subanalysis of subjects aged ≥ 65 years who participated in the 3 phase III perampanel studies was undertaken to determine efficacy and safety in these patients. Efficacy (change in seizure frequency/28 days and 50% responder rate) in the elderly subgroup was found to be consistent with the adult population. Adverse event rates were also largely similar, with some exceptions. Because risks of falls, dizziness, and fatigue were greater in the elderly, careful titration of perampanel in patients aged ≥ 65 years is suggested, especially at higher doses, where balancing tolerability and clinical response is necessary.

Perampanel efficacy and safety by gender: Subanalysis of phase III randomized clinical studies in subjects with partial seizures

The antiepileptic drug (AED) perampanel is approved in ≥40 countries as adjunctive therapy for drug‐resistant partial seizures in patients with epilepsy. This post hoc analysis of pooled data from three phase III, double‐blind, randomized studies of perampanel examines between‐gender differences in perampanel efficacy and safety. Of the 1,478 subjects in the pooled analysis (719 male, 759 female), 1,109 were included in the pharmacokinetic/pharmacodynamic analysis. Perampanel oral clearance was 17% lower in female than in male patients not receiving enzyme‐inducing AEDs. Pooled efficacy analysis revealed that seizure frequency was reduced with perampanel treatment regardless of gender; a greater numerical reduction in seizure frequency and increased responder rates occurred in female participants at perampanel doses of 4, 8, and 12 mg. Tolerability was similar between groups, although common adverse events such as dizziness and headache occurred more frequently in female subjects. Modest elevations in perampanel exposure in female patients may result in meaningful between‐gender differences in efficacy and safety; therefore, dosing should be individualized and clinical response monitored.

Efficacy and safety of perampanel in patients with drug-resistant partial seizures after conversion from double-blind placebo to open-label perampanel

OBJECTIVE To evaluate the efficacy and safety of perampanel in patients with drug-resistant partial seizures after the conversion from double-blind placebo in three phase III studies to open-label perampanel, and to assess the impact of perampanel titration rates through a comparison of weekly vs biweekly dose increases. METHODS Patients who completed the three multinational, double-blind, placebo-controlled, phase III core studies (studies 304, 305, or 306) were eligible to enroll in the extension study (study 307). Patients completing the double-blind treatment (6-week titration, 13-week maintenance) with placebo (DB-PBO) or perampanel (DB-PER) began the extension study with a 16-week blinded conversion period, during which DB-PBO patients were switched to perampanel. Doses were titrated in 2-mg increments (biweekly) to an individualized maximum tolerated dose of perampanel (up to 12 mg/day). Patients then entered a planned, open-label treatment period. RESULTS Perampanel treatment during the extension study reduced total seizure frequency/28 days relative to the double-blind prerandomization baseline regardless of prior perampanel or placebo treatment in the core studies. In the DB-PBO patients, median percent reductions in seizure frequency at the end of the double-blind period, at the end of the conversion period, and at Weeks 40-52 in the open-label maintenance period were 18.6%, 44.3%, and 55.0%, respectively. Seizure control was also improved in the DB-PER patients during the extension period compared to the end of the double-blind period. Responder rates were similar between the 2 patient groups at the end of the conversion period. Perampanel was well tolerated, with the most common treatment-emergent adverse events being dizziness, somnolence, weight increase, irritability, fatigue, and headache. For those patients randomized to the 12 mg group (DB-PER 12 mg), 78.4% reached the daily dose of 10 or 12 mg by the end of the 6-week titration period of the double-blind phase. By the end of the 16-week conversion period of the extension study, 64.0% of DB-PBO patients reached the daily dose of 10 or 12 mg. Seizure frequency reduction was greater after the first 13-week maintenance period of the extension study in the DB-PBO group compared to patients assigned to DB-PER 12mg during the 13-week maintenance period of the double-blind study. CONCLUSION Patients who received placebo in the phase III core DB studies and transitioned to perampanel in the open-label extension study (DB-PBO) achieved seizure control at the end of the conversion period similar to that of patients who had been previously exposed to perampanel (DB-PER) as well as comparable safety outcomes. Patients who received perampanel during the core studies and continued with treatment during the extension study (DB-PER) also showed sustained improvements in seizure control with long-term exposure to perampanel.

Coadministration of lorcaserin and phentermine for weight management: A 12-week, randomized, pilot safety study

To assess the short‐term tolerability of lorcaserin alone or with two dose regimens of phentermine.

Effect of lorcaserin on glycemic parameters in patients with type 2 diabetes mellitus.

Lorcaserin, a 5‐HT2C receptor agonist approved for chronic weight management, is also associated with improvements in glycemic parameters in patients with/without type 2 diabetes mellitus (T2DM), but the extent to which these effects are mediated by weight loss is unknown. This post hoc analysis further examines glycemic data from the Phase III BLOOM‐DM study stratified by weight changes.

Absence of Liver Toxicity in Perampanel-Treated Subjects: Pooled results from partial seizure phase III perampanel clinical studies.

OBJECTIVE The liver plays a major role in the metabolism and elimination of many antiepileptic drugs (AEDs), including perampanel. Some of the metabolites identified for perampanel are likely formed via reactive intermediates, which have the potential to covalently bind to protein and cause idiosyncratic toxicities, including hepatotoxicity. The approved AED perampanel is a selective, noncompetitive AMPA receptor antagonist. The safety and tolerability of perampanel have been well documented in 3 double-blind, randomized, placebo-controlled, phase III studies. Here we report the effects of perampanel on liver function in patients from the phase III studies to assess the potential for liver toxicity. METHODS Following 6-week baseline, patients (≥12 years old) with drug-resistant partial seizures were randomized to once-daily double-blind treatment (6-week titration, 13-week maintenance) with 2, 4, 8, or 12mg perampanel (n=1038) or with placebo (n=442). Clinical laboratory tests for hepatobiliary laboratory parameters were evaluated at baseline and at end of treatment. These included alanine aminotransferase, alkaline phosphatase, aspartate aminotransferase, gamma-glutamyl transpeptidase, and total bilirubin. Treatment-emergent markedly abnormal values (an increase in NCI-CTC grade relative to baseline and a grade ≥2) and treatment-emergent adverse events (TEAEs) related to hepatobiliary parameters were also recorded. RESULTS Mean hepatobiliary values were within normal ranges at baseline and end of treatment for all perampanel groups and placebo. Mean changes from baseline to end of treatment were small. The incidence of markedly abnormal results was very low for perampanel and placebo. TEAEs related to hepatobiliary parameters occurred in 0.4% of perampanel patients and 0% of placebo patients. Hepatobiliary disorders included cholelithiasis (n=3 in perampanel) and abnormal hepatic function (n=1 in perampanel). None of the events were serious or led to perampanel discontinuation. No subject had values that met the criteria for Hys Law. CONCLUSION Hepatobiliary laboratory data and related TEAEs were not notably different between perampanel and placebo treatment groups, and no dose-related trends were observed. Based on the laboratory results from the 3 Phase III studies, perampanel (2, 4, 8, and 12mg) demonstrated no clinically important effects on liver function tests, indicating perampanel is an AED with a low potential for drug-induced liver toxicity.

Analysis of falls in patients with epilepsy enrolled in the perampanel phase III randomized double‐blind studies

To analyze occurrence of falls among patients with partial seizures, with/without secondarily generalized seizures (SGS), and primary generalized tonic–clonic seizures (PGTCS) in the perampanel phase III clinical studies.

Effect of Lorcaserin Alone and in Combination with Phentermine on Food Cravings After 12-Week Treatment: A Randomized Substudy: Lorcaserin, Phentermine, and Craving

This study evaluated the effect of lorcaserin 10 mg twice daily (LOR BID), or with phentermine 15 mg once daily (LOR BID + PHEN QD) and 15 mg twice daily (LOR BID + PHEN BID), in conjunction with energy restriction on food cravings.