Lorcaserin affords a 3.0 to 3.7 percent weight-loss in one year relative to beyond that with placebo when used at the recommended dose.

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Compared with placebo, treatment with Belviq for up to one year was associated with average weight loss ranging from 3 percent to 3.7 percent.

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In one National Cancer Institute-sponsored study, weight loss of greater than 5 percent from baseline was a predictor of poor outcome, independent of cancer stage, type of cancer, and patient performance status.

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The approved labeling for Belviq recommends that the drug be discontinued in patients who fail to lose 5 percent of their body weight after 12 weeks of treatment, as these patients are unlikely to achieve clinically meaningful weight loss with continued treatment.

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