This blog is part of an ongoing series on A Brave New World: Therapeutic Area Deep Dives.

The growth of GLP-1 treatment within diabetes

Glucagon-like peptide 1 (GLP-1) receptor agonists have taken the healthcare world by storm, becoming one of the most successful drug classes of all time, reaching an astonishing $110 billion in sales in 2024 alone¹. Studying how one of the most mature prescription classes in medicine has evolved in just five years provides important strategic lessons for the next generation of healthcare products. What’s driving this meteoric rise? GLP-1s are not just another diabetes medication. Their ability to lower HbA1c levels in Type 2 Diabetes (T2D), combined with impressive weight‑loss benefits, has made them a favorite among both doctors and patients, fueling brand and indication conflation while driving rapid growth and popularity. The expansion of GLP-1 utilization has changed the face of T2D treatment. As more people discover their advantages, GLP-1s are being prescribed earlier in the treatment journey, often displacing longstanding first-line therapies like metformin. This shift is not just about the numbers—it’s changing how physicians and patients think about managing T2D and its many related comorbidities. With GLP-1s leading the way, the landscape of diabetes care is being redefined, offering new hope and better outcomes for millions.

GLP-1s are overtaking other common treatments for diabetes, particularly among the commercially insured

GLP-1s are reshaping treatment for T2D and causing shifts in treatment paradigms across multiple disease areas. Since 2022, the American Diabetes Association has updated its Standards of Care to recommend GLP‑1 receptor agonists as a first‑line therapy for T2D², eroding older and cheaper generics like metformin, which marks a momentous and fundamental change in treatment. By early 2025, nearly 25% of diabetes patients had started a GLP‑1 therapy, up from just 3% four years ago. This rapid growth is driven by GLP-1’s proven ability to lower blood sugar and support meaningful weight loss, making GLP-1s a game-changer for both patients and providers.

The impact of GLP‑1s extends well beyond diabetes and obesity. These therapies are increasingly recognized for their benefits in managing cardiovascular, renal, and metabolic conditions, which are common comorbidities among patients with T2D. By addressing multiple health burdens with a single therapy, GLP‑1s are reshaping how providers think about chronic disease management.

Traditionally, diabetes care relied on a mix of therapeutic classes including insulins, SGLT2 inhibitors, and biguanides such as metformin. As the disease progressed, patients would often switch or add therapies to maintain control. But the balance has shifted dramatically with recent GLP-1 launches.

Biguanides, once responsible for more than 35% of prescriptions, have steadily lost share as patients and providers increasingly turn to GLP‑1s.

The scale of this shift is striking. In the commercial market, GLP‑1 prescription volume grew from 680,000 in January 2020 to 4.7 million in May 2025. Medicare prescriptions followed a similar trajectory, rising from 400,000 to 2 million over the same period. Unique to Medicare, both GLP‑1s and SGLT2s have gained ground, making up 23% and 17% of the market respectively by mid‑2025. Because Medicare patients often face overlapping risks such as chronic kidney disease and cardiovascular complications, multi-indication agents such as the SGLT2s remain an important complementary option alongside GLP‑1s.

Patients diagnosed with diabetes are initiating GLP-1 treatment more quickly than ever before

Since 2021, the average time between a diabetes diagnosis and the initiation of a GLP-1 therapy has decreased by about one month, underscoring how quickly these drugs have moved to the forefront of care. The swing became especially visible in 2023, when nearly half of all T2D patients who began a GLP-1 did so within just one month of their diagnosis. This acceleration coincided with surging demand for semaglutide and tirzepatide, two therapies that have become synonymous with the new era of diabetes and obesity treatment.

However, not all patients can access GLP-1s at the same pace. For Medicare beneficiaries, time-to-treatment is longer due to stricter payer controls and more complex authorization processes. These delays highlight the structural barriers that can slow adoption in populations with higher rates of comorbidities. Still, the broader trend toward earlier initiation reflects a larger paradigm shift in diabetes care, where patients increasingly benefit from the use of GLP-1s early in their treatment journey.

GLP-1s account for 23% of first line diabetes therapy in 2025 – up from 3% in 2021

Since 2019, the American Diabetes Association (ADA) has revised its Standards of Care each year to expand the role of GLP-1 receptor agonists and SGLT2 inhibitors as first-line treatments for T2D². The steady inclusion of GLP-1s and SGLT2s has directed prescribing practices, away from the longstanding reliance on older, generic drugs. Since 2021, GLP-1s have eroded metformin as the preferred first-line therapy for many patients, despite metformin’s lower cost and oral administration. The momentum has only accelerated, contributing to the rising cost of treating diabetes. In the first quarter of 2025, 29% of commercially insured patients initiated their diabetes treatment with a GLP-1. Among Medicare patients, 18% started with a GLP-1 while 24% used an SGLT2, reflecting the higher prevalence of cardiovascular conditions in seniors and the dual benefits SGLT2s provide in heart health. This divergence highlights how payer type and comorbidities influence treatment choices. As more evidence becomes available on the GLP-1s, expect the halo impact on overlapping comorbidities to accelerate their adoption.

Meanwhile, other classes such as insulins and dipeptidyl peptidase-4 (DPP4) inhibitors are rarely used as first-line therapies today, instead serving as follow-on options when additional control is needed. GLP-1s, by contrast, have built a reputation for dramatic weight loss and strong overall effectiveness, making them highly sought after by both patients and providers. While clinical evidence is still emerging, GLP-1s’ potential dual ability to reduce the risk of comorbidities and stabilize patients with fewer additional drugs positions them as a cornerstone of modern diabetes care. Their rapid adoption underscores just how quickly the treatment paradigm has shifted.

GLP-1s and SGLT2s: The New Power Players in Diabetes Care

By 2024, more Medicare patients with T2D are sticking with GLP-1 or SGLT2 therapies as their sole treatment, doubling since 2020. These drugs are proving effective not just for glucose control, but also for heart health, making them especially valuable for older adults with multiple health issues.

While Medicare patients initiating treatment on insulin often need additional medications over time, this reflects not only clinical confidence in these newer therapies, but also the growing recognition that they can simplify treatment regimens for patients who might otherwise juggle multiple prescriptions.

Commercially insured patients show a similar trend: 36% who began GLP-1 therapy in 2024 did not add another drug within a year, a significant rise from 13% in 2020. In contrast, more than 80% of those starting SGLT2 or insulin added another medication. Since commercial patients tend to be younger and healthier than Medicare beneficiaries, early GLP-1 use is reinforcing its role as a reliable foundation for diabetes care and could be a contributing factor to rising rates of monotherapy.

The Bottom Line

GLP‑1 therapies are changing the game for T2D, and their influence is continuing to spread across the broader chronic disease landscape. These medications do much more than just manage blood sugar—they’re quickly becoming a cornerstone of modern healthcare. As the field evolves, it’s crucial for healthcare leaders and organizations to stay agile, adapt to new trends, and focus on what matters most for patients and providers, namely:

• GLP‑1s are now first‑line therapies: Adoption has accelerated from just 3% in 2021 to more than 23% in 2025, displacing long‑standing generics like metformin. Strategic planning must reflect this new standard of care.
• Broader utility drives market dominance: GLP‑1s address not only diabetes and obesity, but also cardiovascular and other metabolic comorbidities, creating opportunities to position them as multi‑condition solutions. As more evidence emerges on their utilization, expect this to continue to grow.
• Earlier initiation is reshaping patient journeys: Patients are starting GLP‑1 therapy within weeks of diagnosis, underscoring the need for streamlined access pathways and payer alignment to reduce delays, especially in Medicare populations.
• Divergence across payer type matters: Commercial patients adopt GLP‑1s earlier and often remain on monotherapy, while Medicare patients face stricter controls and higher comorbidity burdens. Tailored strategies by payer segment are essential.
• Simplification of regimens is a competitive advantage: A growing share of patients, both commercial and Medicare, are managing diabetes with GLP‑1s or SGLT2s alone. Highlighting reduced polypharmacy and improved outcomes strengthens value propositions with providers and payers. Patient demand is shaping the market.

GLP-1 therapies are shaking up the world of diabetes and obesity care, opening new doors for both patients and pharmaceutical companies. As these treatments become more popular, they’re changing how the industry approaches chronic disease—bringing both fresh opportunities but also new challenges. Companies that stay ahead of the curve and adapt their strategies now will be ready to lead the next wave of innovation in obesity care. Looking to build a winning obesity strategy? Connect with IQVIA to explore what’s next in the obesity market.

References:

1. The Global Use of Medicines Outlook Through 2029. Accessed October 15, 2025.
2. American Diabetes Association Professional Practice Committee, ElSayed NA, McCoy RG, et al. Summary of Revisions: Standards of Care in Diabetes—2025. Diabetes Care. 2025;48(Supplement_1):S6-S13. doi:10.2337/dc25-SREV