This systematic review and meta-analysis evaluated the effectiveness of lorcaserin, a selective serotonin 2C receptor agonist, for weight reduction. Five randomized controlled trials involving over 9,000 patients were included. Lorcaserin administered once or twice daily resulted in statistically significant weight loss of 1.95kg and 2.74kg respectively compared to placebo. Lorcaserin also improved other outcomes like waist circumference and cardiometabolic parameters. The most common adverse effects with lorcaserin were headache, upper respiratory infection, and dizziness. Long term studies are still needed to evaluate lorcaserin's effects on sustained weight loss and cost-effectiveness.

1. Lorcaserin for body weight reduction : A systematic review and meta-
analysis
Leite, B.F.1 ; Leão, L.S.C. 1 ; Buehler A. M.2; Pereira T. V. 2
1 Brazilian Ministry of Health 2 Hospital Alemão Oswaldo Cruz
INTRODUCTION
According to the World Health Organization (WHO), obesity worldwide has almost doubled since
1980. Currently, most European countries have a prevalence of overweight (BMI ≥ 25) or obese (BMI ≥ 30)
ranging between 50% and 66% of the population, as in America, countries like the United States and Brazil
this prevalence is 67% and 40%1. A nonlinear regression study estimates a 33% increase in the prevalence
of adult obesity and 130% in the prevalence of severe obesity over the next two decades2.
The increased concern about obesity comes from its increasing prevalence and now represents a
threat to public health3,4. Overweight and obesity are associated with increased risk of developing other
chronic diseases such as type 2 diabetes mellitus, dyslipidemia, systemic hypertension, cardiovascular
disorders, skeletal muscle disorders (such as osteoarthritis), obstructive apnea sleep, some cancers and
mortality. This fact also implies high costs for the health system, patients and society as well as loss of quality
of life due to obesity and its comorbidities 5.
The main goal of treatment for obesity either surgical or medical (non-surgical) is to reduce the
weight and body mass indict (BMI), lower waist circumference, achieving partial or total remission of T2DM
and control the metabolic syndrome and hypertension. In Brazil, drug treatment possibilities have become
increasingly restricted. Recently, ANVISA introduced again in the market derivatives amphetamine
(fenproporex, mazindol and amfepramone) after three years of withdrawal from the market for safety
reasons.
New technologies are highly desirable in the treatment of this disease, but not all medications are
indicated for all patients and safety issues should be an additional concern about the success of treatment. In
this regard, the objective of this systematic review is to summarize the available evidence on the lorcaserin, a
selective serotonin 2C receptor agonist used in the treatment of obesity.
METHODS
Following the methodological guidelines for the development of PTC Ministry of Health, was first
drafted the guiding question of the study through the PICO, then a search was conducted in the main
databases (PubMed, Embase, Cochrane, Lilacs and CRD). Each study recovered in the databases was
selected and evaluated by two independent researchers, their inconsistencies resolved by consensus, when
there was no consensus, the assessment of a third investigator was requested. To assess the risk of bias on
the results found in the selected studies, we used the Cochrane Collaboration tool for assessing the risk of
bias in randomized clinical trials6.
Statistical analysis was performed using Review Manager 5.3 (RevMan). The evaluated outcomes
were summarized quantitatively using the Mantel-Haenszel model for the variables calculated by measuring
the relative risk, and the inverse of the variance for the variables calculated by the average difference metric.
Both models were calculated using the random effect. Heterogeneity between the results of the pooled
studies was assessed by the degree of inconsistency (I2), and confirmed the significant heterogeneity by
Cochran Q test with P <0.1.
It found a total of 555 articles through research carried out in the aforementioned databases. After
deleting the duplicate studies, was conducted a pre-selection of independent double check by reading the
title and abstract, 424 were excluded because they are not relevant to the proposed objective, leaving 18
potentially eligible studies to complete reading. Carried out a complete reading of the articles, 5 studies met
eligibility criteria and were included in the systematic review.

2. Lorcaserin for body weight reduction : A systematic review and meta-
analysis.
Leite, B.F.1 ; Leão, L.S.C.1 ; Buehler A. M. 2; Pereira T. V. 2
1 Brazilian Ministry of Health 2 Hospital Alemão Oswaldo Cruz
RESULTS
Most of the trials had 3 comparative groups, evaluating the medication used once and twice daily
compared to placebo. We first compared the two active groups and if there were no differences between
then, we grouped them in only one. If we identified statistical differences between the two dosages, we
considered the results by dosage.
For the body weight reduction, lorcaserin administrated once a day reduced the body weight by
1.95 kilograms [Kg, (95% CI -2.71;-1.18); I2 = 55%]. Lorcaserin administrated twice daily reduced the body
weight by 2.74 kilograms [95% CI (-3.24;-72.23); I2=25%]. Lorcaserin showed a positive and significant effect
for all the others outcomes investigated.
RESULTS
Despite the profile of the adverse reaction were mild, it increased the risk for the most adverse
reaction commonly reported by the trials.
Considering that the medication is not commercially available, it is not possible to estimate the
treatment cost and its cost-effectiveness. Furthermore, since this is a new technology, long-term follow up
studies and cost-effectiveness analysis are high desirable to better understanding the effect of lorcaserin on
body weight.
Adverse events Total
Events -
Lorcaserin
Total Events -
Placebo
I²
(%)
Relative Risk
Headache 781 361 0 1,68 [1,49 – 1,89]
Upper respiratory
infection
562 402 79 1,00 [0,72 – 1,39]
Nasopharyngitis 573 417 19 1,08 [0,94 – 1,25]
Dizziness 365 138 34 1,97 [1,50 – 2,59]
Nausea 380 194 6 1,49 [1,25 – 1,79]
Diarrhea 265 186 59 1,06 [0,76 – 1,49]
Urinary tract
infection
315 193 0 1,28 [1,07 – 1,52]
Fatigue 315 127 0 1,89 [1,55 – 2,31]
Total (95% CI)

3. Lorcaserin for body weight reduction : A systematic review and meta-
analysis
Leite, B.F.1 ; Leão, L.S.C.1 ; Buehler A. M. 2; Pereira T. V. 2
1 Brazilian Ministry of Health 2 Hospital Alemão Oswaldo Cruz
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