lorcaserin and Serotonin-Syndrome

Options for treating obesity remain limited despite it being a chronic, recurrent and morbid condition. New drugs that are proposed for its treatment encounter strong reluctance by regulatory agencies and many doctors.. This review will focus on the safety of an older drug, orlistat (the only one still approved in the European Union) and a newer recently FDA-approved one, lorcaserin. Both are approved as long-term monotherapy for obesity in the United States of America and they have demonstrated median weight loss of nearly 3% over placebo.. Research, development and approval of new anti-obesity drugs are necessary for improved management of this chronic condition. Orlistat and lorcaserin are two FDA-approved drugs with limited overall efficacy. Nevertheless they are useful weapons for at least some obese individuals. Orlistat has a long and solid safety profile, whereas the safety of lorcaserin is still a matter of debate, mainly due to a lack of long-term data. However, lorcaserin's selective agonism on 5HT2c serotonin receptors diminishes concerns about valvulopathy associated with other serotonin agonists, such as fenfluramine.

Topics: Anti-Obesity Agents; Benzazepines; Chemical and Drug Induced Liver Injury; Drug Interactions; Heart Valve Diseases; Humans; Lactones; Malabsorption Syndromes; Neoplasms; Orlistat; Serotonin Syndrome; United States; United States Food and Drug Administration

Lorcaserin is a selective serotonin 2C receptor (5-HT2C) agonist approved in the United States for use in chronic weight management as an adjunct to a reduced-calorie diet and increased physical activity. Its pharmacologic activity is limited to 5-HT subtype 2 receptors. The potency of lorcaserin for the 5-HT2C receptor is 14-fold greater than its potency for the 5-HT2A receptor and 61-fold greater than its potency for the 5-HT2B receptor. Although 5-HT receptors have been implicated in serotonin syndrome, the precise pathogenesis is unknown. Given a theoretic risk for this syndrome in patients administered lorcaserin either alone or in combination with certain serotonergic agents (eg, selective serotonin reuptake inhibitors [SSRIs] and serotonin-norepinephrine reuptake inhibitors [SNRIs]), patients taking prohibited serotonergic agents were excluded from the Phase III clinical trials. This retrospective analysis evaluated the tolerability of lorcaserin in patients who took protocol-allowed or proscribed serotonergic agents for varying durations of up to 1 year during the BLOOM, BLOSSOM, and BLOOM-DM studies.. Patients randomly assigned to receive either lorcaserin 10 mg QD, lorcaserin 10 mg BID, or placebo and who took a spectrum of serotonergic agents were evaluated at week 52 of treatment (814 and 624 patients receiving lorcaserin and placebo, respectively, were found to have taken allowed or prohibited serotonergic agents during these trials). After the use of a proscribed serotonergic agent was discovered, these patients were discontinued from the trial and followed.. None of the patients in the serotonergic agent subpopulation or in the overall safety population met the clinical criteria of serotonin syndrome. The proportions of patients experiencing any adverse event (AE) were balanced in the lorcaserin and placebo groups in the prohibited serotonergic agent subpopulation. The prevalences of the most common AEs were similar between the serotonergic agent subpopulation and the overall safety population.. The concurrent use of lorcaserin and prohibited or allowed serotonergic agents did not appear to have increased the spectrum or intensity of AEs potentially associated with serotonin excess in this limited dataset. However, the sample population was too small to rule out an effect on a rare event such as serotonin syndrome. ClinicalTrials.gov identifiers: NCT00395135, NCT00603902, and NCT00603291.

Topics: Adult; Anti-Obesity Agents; Benzazepines; Drug Interactions; Female; Humans; Male; Middle Aged; Obesity; Overweight; Receptor, Serotonin, 5-HT2C; Retrospective Studies; Serotonin 5-HT2 Receptor Agonists; Serotonin Agents; Serotonin Syndrome; Weight Loss