Clinicians may have some ambivalence about employing pharmacologic therapies for weight loss-based upon several reality-based observations: 1) Some weight-loss drugs have been taken off the market after a brief sojourn due to serious toxicity (e.g., dexfenfluramine, of notorious Fen-Phen history); 2) Some weight-loss drugs have been taken off the market after sustained use, even though early utilization seemed safe enough (e.g., sibutramine [Meridia]); 3) Many patients who embark upon pharmacotherapeutic courses of weight-loss medication do not lose an amount of weight that is meaningful to them cosmetically (essentially all currently available medications).
One of the primary reasons that patients become dissatisfied with weight-loss pharmacotherapy is that the amount of weight lost does not typically result in achievement of ideal body weight, or anything even close to that. Our role in use of weight-loss agents should include re-orientation of the patient to include not just cosmetic effects of obesity, but long-term health consequences such as metabolic derangement, hypertension, diabetes, and cancer risks.
Currently available anorectic agents do perform well enough to achieve meaningful thresholds of weight reduction that lead to favorable metabolic changes. Two placebo-controlled clinical trials of lorcaserin (Belviq) [BLOOM and BLOSSOM, combined n = 6380] can inform us about what type of impact to anticipate with this 5-HT2c agonist:
At one year of lorcaserin treatment, 47% had lost at least 5% of their body weight, and 22% had lost at least 10% of their body weight. As has been observed in numerous prior interventions that achieve this degree of weight loss, improvements in glycemic status, blood pressure, and lipids were also seen. Although an oral “magic bullet” to assist patients in attaining ideal body weight would be desirable, lorcaserin provides modest — but clinically relevant — weight loss.
Source: Aronne L et al. Postgraduate Med 2014;126:7-18.