Wegovy is a high-dose injectable once-weekly Semaglutide. Among all the weight loss drugs, Wegovy is considered superior. It has been estimated to cause up to 16% body weight loss from the baseline.
Wegovy is a class of drugs called GLP-1 analogs. It is the brand name of the injection Semaglutide.
Semaglutide is also available as a once-daily oral tablet by the brand name of Rybelsus and as a once-weekly injection “Ozempic“.
The recent FDA approval of Wegovy, a high-dose once-weekly Semaglutide, in adults with or without Diabetes is considered one of the game-changing medicine in the management of obesity and especially in patients with Diabesity.
Wegovy weight loss compared with other FDA-approved weight loss drugs:
Before the FDA approval of Wegovy, a high dose once-weekly Semaglutide, five drug combinations were approved by the FDA, ACE (Americal College of Endocrinology), and AACE (American Association of Clinical Endocrinologists). These drugs combinations were:
- Orlistat (Xenical)
- Liraglutide (Saxenda, Victoza)
- Lorcaserin (Belviq)
- Phentermine/ Topiramate ER (Qsymia)
- Naltrexone ER/ Bupropion ER (Contrave)
Except for Liraglutide (Saxenda, Victoza), all the other four drugs are only recommended for weight loss. Liraglutide is an anti-diabetic drug similar to Semaglutide.
It is a GLP-1 analog and is used to treat diabetes and obesity. Hence, it was the only drug approved for the treatment of Diabesity.
The Oral Tablet formulations of Semaglutide, Rybelsus, and the low-dose once-weekly injection Semalgutide, Ozempic, are primarily indicated for the treatment of Diabetes.
Wegovy, the high-dose once-weekly formulation of Semaglutide is primarily indicated for weight loss in obese individuals, like the high-dose Liraglutide. However, it also improves Diabetes at the same time.
Apart from its role as an anti-diabetic medicine, Semaglutide is also considered to be superior to the other approved weight loss medications.
Here is a summary of weight loss comparisons in the clinical trials for the approved drugs:
Orlistat inhibits the absorption of dietary fats. It is especially effective in individuals who ingest lots of fats.
Orlistat is primarily indicated and approved for the treatment of obesity. It is also available over the counter in low doses by the brand name ALLI.
The maximum weight loss observed was 9.8% at the end of one year. Weight loss of 10% was observed in 37% compared to 19% in the placebo group [Ref]
Liraglutide (Saxenda, Victoza):
Liraglutide is a GLP-1 analog and has a mechanism of action similar to Semaglutide (Wegovy).
It is indicated for the treatment of obesity and diabetes mellitus type 2. Like Wegovy, when liraglutide is used primarily for the treatment of obesity, higher doses are recommended.
10% weight loss was observed in 26.1% of patients in the liraglutide 3 mg group versus 6.3% in the placebo.
In the SCALE Diabetes Trial, 6%, 4.7%, and 2% weight loss was observed with liraglutide 3 mg, 1.8 mg, and placebo respectively [Ref].
Lorcaserin activates serotonin receptors and acts as an appetite suppressant. It is primarily used to treat obesity.
Lorcaserin has been withdrawn from the markets recently because of its association with certain cancers.
10% weight loss was seen in 22.6% in the lorcaserin group and 7.7% in the placebo [Ref].
Qsymia contains two drugs: Phentermine and Topiramate. Phentermine is a stimulant drug that suppresses appetite.
Topiramate is primarily used to treat certain types of seizures. However, it is combined with phentermine and used to treat obesity.
10.9% weight loss occurred with phentermine/topiramate CR 15/92 mg. 10% or more weight loss occurred in 67.7% of the high-dose phentermine/topiramate group vs 13% in the placebo [Ref].
Naltrexone is an opioid receptor inhibitor while bupropion is an atypical antidepressant. Contrave is a combination of the two drugs and is used as an appetite suppressant.
In the COR-1 and COR-2 trials, it resulted in a weight loss of 5.4% and 5.6% compared to 1.3% and 1.2% in the placebo.
A weight loss of 10% or more was observed in 21% and 28% of the Naltrexone ER/ Bupropion ER groups vs 7% and 6.1% in the placebo at 56 weeks [Ref].
In contrast to the above weight-loss drugs, Wegovy caused a weight loss of 14.9% in the STEP-1 Trial and 16% in the STEP-3 Trial [Ref].
It is also important to note that since Semaglutide has a half-life of about five days, it is administered once weekly compared to all the above-mentioned medicines approved for weight loss.
Is Semaglutide equally effective at lower doses?
The weight loss effect of Semaglutide administered subcutaneously at a dose of 2.4 mg once weekly is dramatic, however, higher doses may be associated with more adverse events.
Rybelsus is an oral daily administered Semaglutide available as 3 mg, 7mg, and 14 mg tablets. It is primarily indicated for the treatment of Diabetes Mellitus Type 2.
Rybelsus significantly caused weight loss compared to Trulicity (Dulaglutide) in the Pioneer 4 trial.
In the Sustain-1 Trial, the average weight loss observed with 0.5 mg and 1.0 mg once weekly Semaglutide (Ozempic ) was observed to be around 3.7 kgs and 4.5 kgs respectively.
Data from real-world patients who were using Ozempic was extracted from social media and analyzed. Most patients were satisfied with using Ozempic and observed significant weight loss.
Here is a summary of the weight loss effects of Wegovy, Rybelsus, and Ozempic:
Semaglutide 2.4 mg once weekly is more effective and superior to all the other drugs approved for weight loss to date.
In addition, it significantly improves glycated hemoglobin and may reverse Diabetes and Diabesity.
Bariatric surgery is also evolving and is associated with impressive weight loss that usually exceeds 50% of the baseline body weight.