In recent decades, researchers have consistently explored new ways to tackle the global obesity epidemic. While existing methods show significant results, such as the dramatic, long-term weight loss from bariatric surgery or the flexible, non-invasive use of GLP-1 drugs like Ozempic and Wegovy, each approach has its drawbacks. Surgery can be risky and irreversible, while medications often bring unpleasant side effects and a risk of regaining weight once treatment stops.
But what if we could combine the best of both? Imagine achieving the benefits of gastric bypass surgery without going under the knife — simply by taking a pill.
A Boston-based biopharmaceutical company (Syntis Bio) is working on exactly that. The first-in-human study of their new treatment, known as SYNT-101, was presented at the European Congress on Obesity (ECO) in Malaga, Spain. It demonstrated not only safety and good tolerance but also promising signs of appetite regulation and weight loss, without the side effects commonly seen with GLP-1 drugs.
Bariatric Surgery vs. GLP-1 Drugs
Bariatric surgery remains the gold standard for significant weight loss. These procedures reduce stomach size or bypass parts of the small intestine (gastric bypass), physically limiting nutrient absorption. But it’s a serious commitment, typically reserved for people with a BMI over 40 and requires lifelong lifestyle changes, medical supervision, and carries the inherent risks of major surgery.
On the flip side, GLP-1 drugs offer a less invasive option for people with moderate weight gain. Available in pill or injection form, they’re easier to use but often cause side effects like nausea, vomiting, and diarrhea. There’s also concern about losing lean muscle mass and regaining weight once the treatment stops.
Faced with these extremes, many patients are left feeling stuck. That’s where SYNT-101 steps in, a new oral treatment that mimics gastric bypass without cutting or injections.
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Pill Mimics Gastric Bypass
SYNT-101 works by forming a temporary coating in the first part of the small intestine, rerouting how nutrients are absorbed. This “nutrient exclusion” triggers earlier satiety and helps regulate metabolic hormones.
In animal studies, SYNT-101 led to an average weekly weight loss of 1 percent for six weeks and preserved 100 percent of lean muscle mass — better than GLP-1 drugs. In the human pilot study, nine healthy adults (aged 24–53, with BMIs from 19 to 29) received a single dose in liquid form at three increasing dosage levels.
According to the press release, endoscopic imaging confirmed that the coating formed as expected. Blood tests showed increased leptin (signals fullness) and reduced ghrelin (triggers hunger), consistent with preclinical results. Glucose tolerance tests showed delayed glucose absorption, indicating that uptake was occurring later in the digestive tract.
Importantly, there were no adverse events or gastrointestinal symptoms, and participants reported zero pain. Rahul Dhanda, CEO of Syntis Bio, summarized in the news release: “These data validate the potential of SYNT-101 to induce metabolic changes that support glycemic control, weight loss and energy balance.”
Need Of Novel Treatment Options
The temporary lining lasts up to 24 hours. While the initial study used a liquid dose, the treatment is being developed as a once-daily pill for convenience.
“We believe that SYNT-101 will provide a convenient, more sustainable oral alternative and/or complement to systemic therapies such as GLP-1 drugs,” said Dhanda in the statement. “The millions of people living with obesity need novel treatment options that are safe, effective and avoid the high costs and severe side effects that often accompany available treatment options.”
Larger clinical trials are planned, and Syntis Bio aims to submit an Investigational New Drug (IND) application to the FDA in late 2025. As Dhanda added: “We are eager to replicate these data in our upcoming Phase 1 clinical trial and further explore the ability of SYNT-101 to produce sustainable, safe, effective weight loss by reducing fat, preserving lean muscle and stimulating natural production of satiety hormones to prevent weight regain.”
This article is not offering medical advice and should be used for informational purposes only.
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Article Sources
Our writers at Discovermagazine.com use peer-reviewed studies and high-quality sources for our articles, and our editors review for scientific accuracy and editorial standards. Review the sources used below for this article:
American Society for Metabolic and Bariatric Surgery: Bariatric Surgery More Effective and Durable Than New Obesity Drugs and Lifestyle Intervention
European Congress on Obesity: SYNT-101: First-in-Human Evaluation of a Novel Pharmacologic Therapeutic to Replicate Gastric Bypass for Management of Obesity
F1000 Reports Medicine: Quick fix or long-term cure? Pros and cons of bariatric surgery
Harvard Health Publishing: GLP-1 diabetes and weight-loss drug side effects: "Ozempic face" and more
Having worked as a biomedical research assistant in labs across three countries, Jenny excels at translating complex scientific concepts – ranging from medical breakthroughs and pharmacological discoveries to the latest in nutrition – into engaging, accessible content. Her interests extend to topics such as human evolution, psychology, and quirky animal stories. When she’s not immersed in a popular science book, you’ll find her catching waves or cruising around Vancouver Island on her longboard.