Why GLP-1 drugs won’t replace insulin in diabetes care
GLP-1 drugs are revolutionizing diabetes treatment, but does their success mean insulin’s days are numbered? Not even close. While these breakthrough therapies are transforming blood sugar management and weight loss, millions of patients will continue to depend on insulin to survive. Deenadayalan Bakthavatsalam, CEO of rBIO, explains why insulin remains indispensable, what the GLP-1 boom means for the future of diabetes care, and why making insulin more affordable and accessible is as important as ever.
GLP-1 medicines have changed the conversation around diabetes and obesity. Drugs in this class help the body release more insulin when blood sugar is high, reduce glucagon, slow stomach emptying, and reduce appetite. For many people with type 2 diabetes, this can mean better glucose control and weight loss, generally with a low risk of hypoglycemia when these medicines are used without insulin or certain other glucose-lowering drugs.
This is a major scientific and clinical advance. It has also led some investors to question whether insulin will still be needed. But it does not make insulin obsolete.
The reason is simple: GLP-1 medicines work by helping the body use its own insulin system more effectively. They depend on functioning pancreatic beta cells. In early or moderate type 2 diabetes, many patients still have enough beta-cell function for GLP-1 therapy to work well. But as diabetes progresses, beta-cell function can decline. When the body can no longer produce enough insulin, patients with type 2 diabetes still need insulin therapy.
For people with type 1 diabetes, insulin is not optional. Their immune system destroys the beta cells that produce insulin. Without insulin replacement, blood sugar can rise dangerously, leading to diabetic ketoacidosis, coma, and death. GLP-1 medicines may have supporting roles in selected patients, but they cannot replace the missing hormone.
Insulin acts quickly and directly on the body’s cells to lower blood sugar and thus remains essential in hospitals, emergency care, pregnancy-related diabetes, severe hyperglycemia, diabetic ketoacidosis, and advanced insulin-deficient type 2 diabetes. In these settings, insulin is not just another diabetes drug; it is a life-saving hormone.
For investors and healthcare leaders, the message is clear. GLP-1 drugs are expanding the metabolic-health market, but they do not eliminate the need for insulin. Instead, they highlight the growing global demand for better diabetes care. Insulin remains one of the most clinically validated, indispensable, and globally needed biologic medicines.
This continuing need reinforces rBIO’s mission to develop a more cost-efficient insulin manufacturing process and license that technology to manufacturing partners worldwide.
Dr. Judith Shizuru, co-founder of Jasper Therapeutics, now Kira Pharmaceuticals, and member of rBIO’s board of directors, stated: “The rapid spread of diabetes worldwide represents a significant unmet medical need.”
The future of diabetes treatment will not be a choice between GLP-1 therapies and insulin. Both will continue to play important, and sometimes complementary, roles. GLP-1 therapies improve metabolic control for many patients, while insulin remains the foundation for those who cannot produce enough of it.
Affordable, reliable insulin access is still a global healthcare priority.
(1) American Diabetes Association’s Standards of Care in Diabetes 2026.