FDA approves the launch of Qsymia, a new compound diet pill

The U.S. Food and Drug Administration (FDA) approved the compound weight loss drug Qsymia (a sustained release agent containing phentermine and topiramate) (previously known as Qnexa). The drug is approved for use in obese individuals with a body mass index (BMI) ≥ 30 or those who have a BMI ≥ 27, and these patients have at least one weight-related disease such as hypertension, type 2 diabetes, or hyperlipidemia.

Dr. Janet Woodcock, director of the FDA's Center for Drug Evaluation and Research, said: "Qsymia needs to work with healthy diets and lifestyles to treat obese or overweight patients who have at least one comorbid condition."

Phentamine is suitable for short-term weight loss in obese or overweight adult patients undergoing physical exercise and dieting. Topiramate is used to treat the onset of certain types of epilepsy and to prevent migraines.

The daily recommended dose of Qsymia contains phentermine 7.5 mg and topiramate 46 mg. Some patients can also buy a higher dose of the compound (containing phentermine 15 mg and topiramate 92 mg)

Two randomized, placebo-controlled trials evaluated the safety and efficacy of Qsymia. The trial included approximately 3,700 obese or overweight individuals with or without weight-related disease who were treated for 1 year. All subjects also received lifestyle treatment. The results showed that after one year of receiving the recommended dose and high dose of Qsymia treatment, the subjects’ body weight decreased by an average of 6.7% and 8.9%, respectively, which was a greater reduction than the placebo group. About 62% and 69% of patients taking the drug lost at least 5% of their body weight, compared with 20% of patients in the placebo group.

Patients who have not lost at least 3% of their body weight after 12 weeks of Qsymia treatment continue to use the original dose and it is impossible to achieve and maintain weight loss. Therefore, patients using the recommended dose of Qsymia should be assessed for weight loss after 12 weeks of treatment to determine whether to stop treatment or receive a higher dose of treatment. If the patient does not lose at least 5% of body weight after 12 weeks of receiving a higher dose, Qsymia treatment should be discontinued because these patients cannot achieve clinical long-term weight loss if they continue treatment.

It is contraindicated for pregnant women because Qsymia may damage the fetus. Data from the study indicate that there is a dangerous increase in the risk of splitting (cleft or cleft lip) in the fetus exposed to topiramate during early pregnancy. Women of childbearing age should undergo pregnancy tests before starting treatment with Qsymia and during treatment, and take effective contraceptive measures.

Qsymia is contraindicated in patients with glaucoma or hyperthyroidism. Qsymia can increase heart rate. The effect of this drug on heart rate or heart rate in patients at high risk of stroke is not yet clear. Therefore, this medicine is not recommended for patients who have had a heart attack or stroke in the recent past (within 6 months) and have a history of unstable heart disease or stroke. Patients taking this medication should also routinely monitor heart rate changes, especially when starting treatment or when increasing the dose. The manufacturer of the drug will also conduct postmarketing studies, including long-term cardiovascular outcome tests that assess the risk of major cardiovascular adverse events in Qsymia.

The most common adverse reactions to Qsymia include numbness of the limbs, dizziness, abnormal taste, insomnia, dry mouth, and constipation.