GLP-1 Tirzepatide ReviewIndependent · S.J Partners LLC
Prices 6 verified of 54 Rubric v1.0-draft Prices verified 0 of 54 Evidence records 32 verified Corrections open log

Trial review

OASIS 4: Oral Semaglutide 25 mg, Explained

Oral semaglutide 25 mg for weight management

Dr. Parmis, Editorial Lead · Jonathan Michael Snipes, MD, Medical Reviewer

Published Updated Sources captured Medically reviewed not yet — why

Direct answer

OASIS 4 was a phase 3, randomised, double-blind, placebo-controlled funded by Novo Nordisk. 13.6% mean weight reduction on the treatment-policy estimand versus 2.2% placebo; 16.6% versus 2.7% among those who remained on treatment. One in three adherent participants achieved 20% or greater reduction. That figure belongs to the population, dose and 64 weeks of treatment plus a 7-week off-treatment follow-up shown below, and describes a group average rather than a prediction for any individual.

Answer last reviewed: 2026-07-24Evidence:
OASIS 4 at a glanceVerified
DesignPhase 3, randomised, double-blind, placebo-controlled
Population307 adults with obesity (BMI 30 or above) or overweight (BMI 27–29.9) with at least one weight-related comorbidity, excluding people with diabetes. Mean baseline weight 106 kg, mean BMI 38
Sample size307 randomised 2:1 (205 active, 102 placebo)
InterventionOral semaglutide 25 mg once daily, with a 12-week dose escalation
ComparatorPlacebo
Duration64 weeks of treatment plus a 7-week off-treatment follow-up
Primary endpointCo-primary: percentage change in body weight and the proportion achieving at least 5% reduction at week 64
Main result13.6% mean weight reduction on the treatment-policy estimand versus 2.2% placebo; 16.6% versus 2.7% among those who remained on treatment. One in three adherent participants achieved 20% or greater reduction
NCT NCT05564117 · DOI 10.1056/NEJMoa2500969Last source check: 2026-07-24
How to read OASIS 4 without over-reading it
1Who was eligible307 adults with obesity (BMI 30 or above) or overweight (BMI 27–29.9) with at least one 2What they receivedOral semaglutide 25 mg once daily, with a 12-week dose escalation3What it was compared againstPlacebo4For how long64 weeks of treatment plus a 7-week off-treatment follow-up5What was measured firstCo-primary: percentage change in body weight and the proportion achieving at least 5% re6What the group average was13.6% mean weight reduction on the treatment-policy estimand versus 2.2% placebo; 16.6% 7What it does not tell youA group average is not a prediction for any individual reader.
Show this figure as a table
StepStageWhat happens
1Who was eligible307 adults with obesity (BMI 30 or above) or overweight (BMI 27–29.9) with at least one weight-related comorbidity, excluding people with diabetes. Mean baseline weight 106 kg, mean BMI 38
2What they receivedOral semaglutide 25 mg once daily, with a 12-week dose escalation
3What it was compared againstPlacebo
4For how long64 weeks of treatment plus a 7-week off-treatment follow-up
5What was measured firstCo-primary: percentage change in body weight and the proportion achieving at least 5% reduction at week 64
6What the group average was13.6% mean weight reduction on the treatment-policy estimand versus 2.2% placebo; 16.6% versus 2.7% among those who remained on treatment. One in three adherent participants achieved 20% or greater reduction
7What it does not tell youA group average is not a prediction for any individual reader.
Strip any step and the result stops meaning what the trial found.
Reported resultsWharton S, Lingvay I, Bogdanski P, et al. N Engl J Med 2025;393(11):1077-1087
Oral semaglutide, treatment-policy14%Oral semaglutide, adherent17%Placebo2%
Show this figure as a table
ItemWeight changeEvidence
Oral semaglutide, treatment-policy14%Verified
Oral semaglutide, adherent17%Verified
Placebo2%Verified
Group means under trial conditions with lifestyle intervention. Not a prediction for any individual reader.
Mean weight reduction by drug and dose, from the trials that produced each figureSeparate trials, different durations and populations
Tirzepatide 15 mg (SURMOUNT-1)21%Oral semaglutide 25 mg, adherent (17%Injectable semaglutide 2.4 mg (SUR14%Oral semaglutide 25 mg, treatment-14%Orforglipron 17.2 mg (ATTAIN-1)12%Liraglutide (SCALE)8%
Show this figure as a table
ItemMean reductionEvidence
Tirzepatide 15 mg (SURMOUNT-1)21%Verified
Oral semaglutide 25 mg, adherent (OASIS 4)17%Verified
Injectable semaglutide 2.4 mg (SURMOUNT-5)14%Verified
Oral semaglutide 25 mg, treatment-policy (OASIS 4)14%Verified
Orforglipron 17.2 mg (ATTAIN-1)12%Provider-reported
Liraglutide (SCALE)8%Provider-reported
These come from different trials and are not a head-to-head comparison. Durations differ (64 to 72 weeks) and estimands differ. Only SURMOUNT-5 compared two of these drugs directly.
Price against efficacy, for the FDA-approved options
ProductStarting self-pay priceReported mean reductionTrial
Zepbound (tirzepatide) injectable$299/mo directabout 20.9% at 15 mgSURMOUNT-1, 72 weeks
Wegovy pill (oral semaglutide 25 mg)$149/mo starting dose13.6–16.6% depending on estimandOASIS 4, 64 weeks
Wegovy injectable (semaglutide 2.4 mg)$349/mo maintenanceabout 13.7%SURMOUNT-5, 72 weeks
Foundayo (orforglipron)$149/mo starting doseabout 11–12.4% at 17.2 mgATTAIN-1, 72 weeks
Both $149 products are the least effective approved options in this table. That does not make them bad choices — it makes a price comparison that omits efficacy an incomplete one.

Questions readers actually ask

Does this apply to compounded versions?

No. The trial studied an FDA-approved product at studied doses.

Is this drug as effective as tirzepatide?

By mean reduction across separate trials, no. The efficacy ladder above sets out the figures with the trial that produced each one.

Cite this pageCC BY 4.0

GLP-1 Tirzepatide Review. “OASIS 4: Oral Semaglutide 25 mg, Explained.” S.J Partners LLC, 2026-07-24. https://glp1tirzepatidereview.com/research/oasis-4/

When quoting a figure, include the capture date shown beside it rather than the date you read this page. A price without its capture date is not a usable citation.

Report an error
Comparing 0 of 4