A new peer-reviewed paper published in Diabetes, Obesity & Metabolism marks 25 years since insulin glargine — the first once-daily long-acting basal insulin analogue — entered clinical use. For the growing number of people managing diabetes with GLP-1 medications, understanding how basal insulin fits into the treatment landscape can help inform conversations with prescribers.

A Quarter-Century of Basal Insulin

According to the review, insulin glargine became available for clinical use in the year 2000, making it the first once-daily long-acting bioengineered insulin analogue (LAIA) — and what the authors describe as a "true basal insulin." Its arrival marked the decline of a 50-year era of intermediate-acting insulins, specifically neutral protamine Hagedorn (NPH) and lente insulins, both of which required twice-daily administration to manage the body's baseline glucose metabolism. The shift to once-daily dosing represented a meaningful improvement in convenience and, for many patients, in glucose stability.

Why This Matters if You're on a GLP-1 Medication

GLP-1 receptor agonists like semaglutide (Ozempic, Wegovy) and tirzepatide (Mounjaro, Zepbound) work primarily by stimulating insulin release in response to meals and by suppressing glucagon — but they do not replace basal insulin for people who need it. Many individuals with type 2 diabetes use a GLP-1 medication alongside a long-acting insulin like glargine, a combination that targets both meal-related and overnight glucose levels. Understanding the distinct role basal insulin plays — controlling background blood sugar between meals and overnight — helps patients appreciate why their prescriber may recommend both drug classes together.

What the Research Milestone Signals

Anniversary reviews like this one typically synthesize decades of clinical evidence and highlight where treatment is heading. The publication in a major diabetes journal suggests continued scientific interest in optimizing basal insulin therapy alongside newer agents. For patients, this kind of research often precedes updated clinical guidelines or new combination treatment recommendations — developments worth tracking if you take both a GLP-1 drug and insulin.

Key takeaway: Insulin glargine, the once-daily basal insulin that replaced older twice-daily insulins in 2000, is frequently used alongside GLP-1 medications like Ozempic and Mounjaro. If you take both, ask your prescriber how each one is contributing to your glucose control.

What to Watch For

As the full review (beyond the abstract) is now published in Diabetes, Obesity & Metabolism, updated clinical commentary may follow. Patients using GLP-1 therapies for obesity rather than diabetes should note that basal insulin is generally not part of their regimen — but those with type 1 or type 2 diabetes on insulin should stay alert to any guideline updates that cite this body of evidence.

Frequently Asked Questions

According to the peer-reviewed review, insulin glargine became available for clinical use in the year 2000, making it the first once-daily long-acting bioengineered insulin analogue. It is classified as a true basal insulin, meaning it controls background blood sugar levels rather than meal-related spikes.
Many people with type 2 diabetes do use a GLP-1 receptor agonist alongside a long-acting insulin. The two drug classes work differently — GLP-1 drugs help control meal-related glucose and appetite, while basal insulin controls background glucose levels. Whether this combination is right for you depends on your individual situation and should be determined by your prescriber.
The review notes that insulin glargine led to the decline of intermediate-acting insulins — specifically NPH (neutral protamine Hagedorn) and lente — which had been in use for about 50 years and required twice-daily injections. Moving to a once-daily formulation improved convenience and helped more patients maintain consistent basal glucose control.
If you are taking Wegovy or Zepbound purely for weight management and do not have diabetes, basal insulin is not typically part of your treatment plan. This research is most relevant to people who have type 1 or type 2 diabetes and may use insulin alongside a GLP-1 medication.
The review was published in Diabetes, Obesity & Metabolism, a peer-reviewed medical journal, in 2025. Peer-reviewed publications undergo expert evaluation before publication, making them a reliable source of medical information — though individual findings should always be discussed with your own healthcare provider.

As always, any decisions about your diabetes medications — including whether to use a GLP-1 drug, basal insulin, or both — should be made in close consultation with your prescriber, who can tailor treatment to your individual health needs and goals.

Sources
  • Peer-reviewed journal article, 'The Silver Jubilee (2025) of Insulin Glargine: Introducing the Era of Long-Acting Insulin Analogues for Diabetes Mellitus,' Diabetes Obesity & Metabolism, 2025.

This site provides general information only and does not constitute medical advice. All content is sourced to FDA labeling, NIH publications, or peer-reviewed clinical trials. Always consult your prescriber before making any medication decision.