Oral GLP-1-Based Therapeutics in the Obesity-Metabolic Syndrome-Diabetes Continuum: Translational Advances, Clinical

Syed Arman Rabbani1, Manita Saini2,3, Mohamed El-Tanani1

  • 1Clinical Pharmacy & Pharmacology, RAK College of Pharmacy, Ras Al Khaimah Medical and Health Sciences University, Ras Al Khaimah P.O. Box 11172, United Arab Emirates.

Insights

Oral glucagon-like peptide-1 receptor agonists (GLP-1 RAs) offer disease-modifying benefits for obesity and diabetes. Oral formulations overcome limitations of injectables, improving adherence and access for better cardio-renal-metabolic outcomes.

Area of Science:

  • Endocrinology and Metabolism
  • Pharmacology
  • Drug Delivery Systems

Background:

  • The obesity-metabolic syndrome-diabetes continuum involves complex mechanisms like insulin resistance and inflammation, necessitating therapies beyond glucose lowering.
  • Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) demonstrate disease-modifying potential, including weight loss, cardiovascular risk reduction, glycemic control, and renal protection.
  • Injectable GLP-1 RAs face challenges with treatment burden, adherence, and access, limiting long-term efficacy.

Purpose of the Study:

  • To review the mechanistic rationale, formulation science, and clinical development of oral GLP-1 receptor agonists (GLP-1 RAs).
  • To evaluate oral semaglutide as a proof of concept for systemic peptide delivery via the gastrointestinal route.
  • To discuss enabling technologies and future directions for oral peptide therapeutics in metabolic diseases.

Main Methods:

  • Review of mechanistic rationale and formulation science for oral GLP-1 RAs.
  • Critical discussion of biological barriers to oral peptide absorption.
  • Evaluation of enabling technologies for oral peptide delivery.
  • Synthesis of evidence from clinical studies, including the PIONEER program.

Main Results:

  • Oral semaglutide represents a validated approach for oral peptide delivery, overcoming enzymatic degradation and absorption barriers.
  • Enabling technologies like SNAC-based absorption and nanocarriers are crucial for oral peptide bioavailability.
  • Clinical data show meaningful glycemic and weight-loss efficacy, with acceptable safety in type 2 diabetes and chronic kidney disease patients.

Conclusions:

  • Oral GLP-1-based therapeutics are transitioning from formulation innovation to a broader strategy for disease modification in the obesity-metabolic syndrome-diabetes continuum.
  • Emerging oral therapies include non-peptide GLP-1 RAs, dual/triple incretin agonists, and precision dosing.
  • Future research priorities include long-term renal outcomes, access, and implementation strategies for oral GLP-1-based treatments.

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