Safety and tolerability review of lorcaserin in clinical trials

Lorcaserin is a novel selective serotonin 2C receptor agonist indicated by the US Food and Drug Administration for chronic weight management in adults with obesity or overweight with ≥1 comorbidity. The safety and efficacy of lorcaserin were established during two Phase III clinical trials in patients without diabetes (BLOOM and BLOSSOM) and one Phase III clinical trial in patients with type 2 diabetes (BLOOM-DM). Headache was the most common adverse event experienced by patients during all Phase III trials. Additional adverse events occurring in >5% of patients receiving lorcaserin included dizziness, fatigue, nausea, dry mouth and constipation in patients without diabetes, and hypoglycaemia, back pain, cough and fatigue in patients with diabetes. In a pooled analysis of echocardiographic data collected during the three lorcaserin Phase III trials, the incidence of FDA-defined valvulopathy was similar in patients taking lorcaserin and the placebo. Here, the safety profile of lorcaserin at the FDA-approved dose of 10 mg twice daily is reviewed using data from the lorcaserin Phase III programme, with a focus on theoretical adverse events commonly associated with agonists of the serotonin receptor family. Based on the lorcaserin Phase III clinical trial data, lorcaserin is safe and well tolerated in the indicated patient populations.

Effects of lorcaserin on fat and lean mass loss in obese and overweight patients without and with type 2 diabetes mellitus: the BLOSSOM and BLOOM-DM studies

Body composition was determined using dual-energy X-ray absorptiometry (DXA) in a subset of patients without (BLOSSOM) and with (BLOOM-DM) type 2 diabetes who received diet and exercise counselling along with either lorcaserin 10 mg twice daily or placebo. DXA scans were performed on study day 1 (baseline), week 24 and week 52. Baseline demographics of the subpopulations (without diabetes, n = 189; with diabetes, n = 63) were similar between studies and representative of their study populations. At week 52, patients without diabetes on lorcaserin lost significantly more fat mass relative to those on placebo (-12.06% vs -5.93%; p = 0.008). In patients with diabetes, fat mass was also decreased with lorcaserin relative to placebo (-9.87% vs -1.65%; p < 0.05). More fat mass was lost in the trunk region with lorcaserin compared with placebo (without diabetes: -3.31% vs -2.05%; with diabetes: -3.65% vs -0.36%). Weight loss with lorcaserin was associated with a greater degree of fat mass loss than lean mass loss, and most of the fat mass lost for patients without and with diabetes was from the central region of the body.

Role of endogenous ET-1 in the regulation of myocardial blood flow in lean and obese humans

Endothelin is an important determinant of peripheral vascular tone, and increased endogenous endothelin activity contributes to peripheral vascular dysfunction in human obesity. The contributions of endothelin to the regulation of coronary vascular tone in health in humans have not been well studied. We hypothesized that the contribution of endothelin to the regulation of myocardial perfusion would be augmented in human obesity. Using [NH(3)]ammonia positron emission tomography (PET), we measured myocardial perfusion under resting and adenosine-stimulated conditions on two separate days, with and without concurrent exposure to BQ123, an antagonist of type A endothelin receptors (1 micromol/min IV beginning 90 min before measurement). We studied 10 lean and 9 obese subjects without hypertension, hyperlipidemia, or diabetes mellitus. We observed a BQ123-induced increase in resting myocardial perfusion of approximately 40%, not different between lean and obese subjects (BQ123-induced increase in flow: lean 0.12 +/- 0.20, obese 0.32 +/- 0.51 ml/g/min, P = 0.02 BQ123 effect, P = 0.27 comparing response across groups). Although basal flow rates varied by region of the myocardium, the BQ123 effect was seen in all regions. BMI and cholesterol were significantly related to BQ123-induced increases in basal tone in multivariable analysis. There was no baseline difference in the adenosine-stimulated increase in blood flow between lean and obese subjects, and BQ123 failed to augment these responses in either group. These observations suggest that endothelin is an important contributor to the regulation of myocardial perfusion under resting conditions in healthy lean and obese humans, with increased contributions in proportion to increasing obesity.

Wealth from Health: an incentive program for disease and population management: a 12-year project

The future of healthcare is linked with its ability to face the challenges of consumerism. Disease and population management will represent the dominant style of healthcare delivery in the future. This article describes the Wealth from Health programs which utilize current and future technologies to help the healthcare system become a leader in healthcare delivery and to assist many communities at an affordable cost.

Usefulness of positron emission tomography in predicting long-term outcome in patients with diabetes mellitus and ischemic left ventricular dysfunction

We assessed the value of positron emission tomography to predict long-term outcome in patients with diabetes and ischemic left ventricular (LV) dysfunction. Circumferential profiles of nitrogen-13 ammonia (NH3) and fluorine-18 fluorodeoxyglucose uptakes were obtained in 61 patients who had diabetes and ischemic LV dysfunction. Patient profiles were compared with those from a normal database. NH3 and fluorine-18 fluorodeoxyglucose defect sizes and extent of perfusion-metabolism mismatch (percentage of myocardium with fluorine-18 fluorodeoxyglucose uptake minus NH3 uptake >2 SD above the normal difference) were determined. Patients were followed every 6 months. Over a mean follow-up of 4.3 years, cardiac death occurred in 52% of patients who underwent revascularization and 61% of those who underwent medical therapy (p = 0.69). No clinical or imaging variables predicted cardiac death in patients who underwent revascularization. In those who received medical therapy, mismatch in > or =3% of the left ventricle (risk ratio 4.0, p = 0.01) was the only multivariate predictor of cardiac death. Revascularization improved survival of patients who had mismatch of > or =3% at 4 years (p = 0.003) and at 8 years (p = 0.012) of follow-up. Patients who had mismatch > or =3% and ejection fraction <30% had the greatest improvement in survival with revascularization compared with medical therapy (p <0.0001). Revascularization also improved 4-year survival of patients who had NH3 perfusion defects of > or =25% of the left ventricle (p = 0.02). In conclusion, mismatch identifies medically treated patients who have diabetes and LV dysfunction, who are at high risk for cardiac death. Intermediate- and long-term survival of patients who have diabetes and mismatch may be improved with revascularization, and those who have significant mismatch and severe LV dysfunction have the greatest benefit.

Positron emission tomography in cochlear implant and auditory brain stem implant recipients

OBJECTIVE

The purpose of this study was to determine whether similar cortical regions are activated by speech signals in profoundly deaf patients who have received a multichannel cochlear implant (CI) or auditory brain stem implant (ABI) as in normal-hearing subjects.

STUDY DESIGN

Positron emission tomography (PET) studies were performed using a variety of discrete stimulus conditions. Images obtained were superimposed on standard anatomic magnetic resonance imaging (MRI) for the CI subjects. The PET images were superimposed on the ABI subject's own MRI.

SETTING

Academic, tertiary referral center.

PATIENTS

Five subjects who have received a multichannel CI and one who had received an ABI.

INTERVENTION

Multichannel CI and ABI.

MAIN OUTCOME MEASURE

PET images.

RESULTS

Similar cortical regions are activated by speech stimuli in subjects who have received an auditory prosthesis.

CONCLUSIONS

Neuroimaging provides a new approach to the study of speech processing in CI and ABI subjects.