title: Lorcaserin in Obese and Overweight Patients Taking Prohibited Serotonergic Agents: A Retrospective Analysis.
abstract: 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.
authors.affiliation: Department of Psychiatry and Human Behavior, School of Medicine, University of California, Irvine, California; Department of Mental Health, Veterans Affairs Long Beach Healthcare System, Long Beach, California. Electronic address: charles.nguyen@va.gov.
authors.forename: Charles T
authors.initials: CT
authors.lastname: Nguyen
authors.affiliation: Eisai Inc, Woodcliff Lake, New Jersey.
authors.forename: Sharon
authors.initials: S
authors.lastname: Zhou
authors.affiliation: Arena Pharmaceuticals, Inc, San Diego, California.
authors.forename: William
authors.initials: W
authors.lastname: Shanahan
authors.affiliation: Formerly of Eisai Inc, Woodcliff Lake, New Jersey.
authors.forename: Randi
authors.initials: R
authors.lastname: Fain
mesh_terms: D000328:Adult; D019440:Anti-Obesity Agents / Q000009:adverse effects*; D001552:Benzazepines / Q000009:adverse effects*; D004347:Drug Interactions; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000188:drug therapy / Q000503:physiopathology; D050177:Overweight / Q000188:drug therapy* / Q000503:physiopathology; D044405:Receptor, Serotonin, 5-HT2C / Q000378:metabolism*; D012189:Retrospective Studies; D058826:Serotonin 5-HT2 Receptor Agonists / Q000627:therapeutic use*; D018490:Serotonin Agents / Q000009:adverse effects*; D020230:Serotonin Syndrome / Q000139:chemically induced*; D015431:Weight Loss
chemical_list: D019440:Anti-Obesity Agents; D001552:Benzazepines; D044405:Receptor, Serotonin, 5-HT2C; D058826:Serotonin 5-HT2 Receptor Agonists; D018490:Serotonin Agents; C506658:lorcaserin
keywords: lorcaserin; serotonergic agents; serotonin syndrome