Context: Two GLP-1 drugs- Novo Nordisk’s semaglutide and Eli Lilly’s tirzepatide, are now available in the Indian market.
Mounjaro, Ozempic, Wegovy, Semaglutide, Tirzepatide belong to a class of glucagon-like peptide-1 (GLP-1) receptor agonists, originally developed to treat diabetes and obesity.
Relevance of the Topic:Prelims: Key facts about GLP-1 Drugs.
What are GLP-1 Drugs?
- GLP-1 is an incretin hormone and a neurotransmitter naturally secreted from the small intestine and hindbrain in the human body, after one eats a meal. It travels to the pancreas, where it helps to regulate blood sugar by increasing insulin and decreasing glucagon.
- GLP-1 RA (glucagon-like peptide-1 receptor agonists) are a new class of drugs that mimic naturally-occurring gut hormones called incretin (GLP-1 is one such incretin). Thus, they regulate appetite and digestion, helping users feel full faster and consume fewer calories.
- Semaglutide and Tirzepatide both mimic the action of GLP-1. Tirzepatide additionally also mimics the action of another hormone called GIP (glucose-dependent insulinotropic polypeptide).
How GLP-1 Drugs Work?
GLP-1 drugs impact centres in the brain associated with control of hunger and satiety, to effectively tell us that we have had enough to eat and need to stop eating. They work by:
- improving the secretion of insulin that allows more of the glucose in the bloodstream to enter cells where it can be used for energy.
- inhibiting the secretion of the hormone glucagon that stimulates the liver to release stored glucose into the bloodstream.
- slowing down the emptying of the stomach so that the glucose levels in the bloodstream does not spike.
- reducing appetite by signalling to the brain that one is satiated.
The drugs can be self-administered by the patient once a week via subcutaneous injection (similar to insulin). Semaglutide is also available as an oral tablet.
Utility of GLP-1 Drugs:
- Weight loss: Extremely effective for weight-loss helping people lose on an average 15% to 20% of their body weight, equivalent to otherwise lost with bariatric surgeries.
- Diabetes: GLP-1 drugs infusion significantly increases insulin levels and lowers glucose levels in diabetic patients.
- Alzheimer’s: Some evidence shows that the drugs are associated with lower risk of Alzheimer’s and Dementia.
- Other Conditions: Found to be effective and are being studied for conditions including- cardiovascular diseases, kidney disease, non-alcoholic fatty liver disease, and obstructive sleep apnoea. Studies have shown a 69% reduction in heart failure events.
Potential Side Effects of GLP-1 Drugs:
- Common side effects include- nausea, vomiting, acidity, burping, hiccups, diarrhoea, abdominal pain, and appetite loss.
- Rarer complications include- pancreatitis, retinal changes (necessitating eye exams), and increased risk of medullary thyroid carcinoma, especially for those with a family history.