Oral GLP-1: what the evidence base looks like

What this literature is made of

There is a real trial literature here, but comparatively little synthesis. Individual trials can disagree, and without meta-analysis it is easy to find one that supports almost any position.

The distinction that matters most is between synthesis and primary research. A meta-analysis pools trials and is the closest thing to a settled answer a field produces. A narrative review is one group's reading of the same material and can be selective without being dishonest. Counting them together, which most citation counts do, obscures exactly the thing you want to know.

How this page is built

Everything above is computed from the citations this site harvested from PubMed and Crossref, not written by hand. When the weekly harvest finds a new paper on this topic, these counts change and the characterisation changes with them. That is the point: a hand-written claim about how strong an evidence base is starts decaying the day it is written.

Publication type is taken as the source records it. That is imperfect — journals label inconsistently, and a paper indexed as a "review" may be a systematic one — so treat the bands as approximate. They are accurate enough to distinguish a trial literature from a commentary literature, which is the distinction that matters.

The strongest work on this topic

Ordered by study design first, then recency. The full set is listed in the references below.

1. Emerging pharmacotherapies for obesity: A systematic review — Kokkorakis M, Chakhtoura M, Rhayem C et al., 2025, systematic review
2. Orforglipron, an Oral Small-Molecule GLP-1 Receptor Agonist for Obesity Treatment — Wharton S, Aronne LJ, Stefanski A et al., 2025, randomised controlled trial
3. Oral Semaglutide at a Dose of 25 mg in Adults with Overweight or Obesity — Wharton S, Lingvay I, Bogdanski P et al., 2025, randomised controlled trial
4. Long-term weight loss effects of semaglutide in obesity without diabetes in the SELECT trial — Ryan DH, Lingvay I, Deanfield J et al., 2024, randomised controlled trial
5. Semaglutide and Cardiovascular Outcomes in Obesity without Diabetes — Lincoff AM, Brown-Frandsen K, Colhoun HM et al., 2023, randomised controlled trial
6. Oral semaglutide 50 mg taken once per day in adults with overweight or obesity (OASIS 1): a randomised, double-blind, placebo-controlled, phase 3 trial01185-6) — Knop FK, Aroda VR, do Vale RD et al., 2023, randomised controlled trial
7. Weight regain and cardiometabolic effects after withdrawal of semaglutide: The STEP 1 trial extension — Wilding JPH, Batterham RL, Davies M et al., 2022, randomised controlled trial