OASIS 4 Study Confirms Efficacy of Once-Daily Oral Semaglutide for Weight Management

A significant advancement in weight management has emerged at the start of the new year, following the approval by the U.S. Food and Drug Administration (FDA) of the 25 mg oral semaglutide tablet, known as Wegovy. This once-daily tablet became available in the United States in early January 2026, designated for chronic weight management as well as reducing the risks of serious cardiovascular events in adults who are obese or overweight and have pre-existing cardiovascular conditions.

Results from the OASIS (Oral Semaglutide Treatment Effect in People with Obesity) 4 clinical trial, recently published in the New England Journal of Medicine, demonstrate that a daily 25 mg dosage leads to substantial weight loss and enhanced physical functionality. The trial’s findings present this mid-dose oral formulation as an effective alternative for individuals who prefer the simplicity of a pill over conventional weekly injections or higher-dose oral medications.

The authors of the study pointed out that many patients express a preference for oral administration mainly due to needle aversion and the potential for skin reactions associated with injections. Importantly, oral semaglutide also eliminates the need for refrigeration, which broadens accessibility for obesity treatment in areas lacking refrigeration infrastructure.

Conducted over a period of 71 weeks, this double-blind, randomized trial involved 307 participants without diabetes, recruited from four different countries. Participants were selected based on a Body Mass Index (BMI) of 30 or greater, or a BMI of 27 accompanied by at least one obesity-related complication, which could include hypertension, dyslipidemia, or obstructive sleep apnea.

The outcomes showed that those taking the 25 mg dose of oral semaglutide experienced an average weight loss of 13.6% from their initial weight, contrasting with a mere 2.2% weight reduction in the placebo group. This mid-range dosing option serves as a beneficial compromise for individuals who do not necessarily require the higher maximum dose of 50 mg but still wish for results that surpass what lower-dose alternatives provide.

The study also aimed to assess several secondary endpoints, including reductions in waist circumference and improvements in systolic blood pressure. Participants receiving semaglutide were significantly likelier to meet substantial weight loss milestones—10%, 15%, and even up to more than 20% weight loss—compared to the placebo group. Additionally, assessments of physical function, indicated by the IWQOL-Lite-CT scores, showed notable improvements. These findings suggest that the weight loss achieved translates into better mobility and overall quality of life for participants.

Sean Wharton, the primary author of the study and head of the Wharton Weight Management Clinic in Burlington, Canada, emphasized the significance of the weight loss and the associated enhancements in metabolic markers linked to oral semaglutide. He noted this development is likely to have a positive effect on both obesity medicine and related metabolic conditions.

Oral semaglutide functions as a GLP-1 receptor agonist, mimicking a natural hormone that plays a role in appetite regulation and calorie intake. Although it is highly effective, the 25 mg dose did have a higher incidence of side effects compared to the placebo group. Reports showed gastrointestinal issues—primarily nausea and diarrhea—occurred in 74% of the semaglutide recipients, while only 42.2% of those in the placebo group reported similar experiences. These results align with the known safety profile associated with GLP-1 medications, reinforcing their clinical applicability.