Lantus is not being discontinued. Sanofi continues to manufacture and sell Lantus in both vial and SoloStar pen formats, and the product is listed as available on the American Society of Health-System Pharmacists (ASHP) drug shortage tracker. The confusion likely stems from the fact that several competing long-acting insulins have recently been discontinued or are being phased out, creating ripple effects in the insulin market.
Why the Confusion Exists
Several insulin glargine products, which are biosimilar versions of Lantus, have recently left or are leaving the market. Biocon discontinued its Semglee vials and pens on December 31, 2025. Eli Lilly is discontinuing Basaglar Tempo pens by the end of 2026. When patients or pharmacists hear that an insulin glargine product is being pulled, it’s easy to assume Lantus itself is affected.
Supply disruptions at pharmacies can also fuel the rumor. If your pharmacy is temporarily out of Lantus, that’s a stocking or distribution issue, not a sign the product is going away. The ASHP confirms both the 10 mL vial and the 3 mL SoloStar pen (five-count box) remain in active production by Sanofi.
Lantus Sales Are Actually Growing
Far from winding down, Sanofi reported Lantus sales of €439 million in Q4 2024, a 63.4% increase over the same period the year before. U.S. sales specifically benefited from competitors leaving the market, which Sanofi described as “windfall sales due to the continued unavailability of a competing medicine.” The company does expect demand to normalize in 2025 as the market settles, but that’s a return to baseline, not a decline toward discontinuation.
Sanofi also sells Toujeo, a higher-concentration insulin glargine, which brought in €290 million in Q4 2024. The company has reason to keep both products on the market since they serve slightly different patient needs.
Biosimilars and What They Mean for You
Lantus now has FDA-approved biosimilar competitors. A biosimilar is a near-identical copy of a biologic drug that has been tested and shown to have no clinically meaningful differences in purity, effectiveness, or safety compared to the original. The two main biosimilars for Lantus are Semglee (insulin glargine-yfgn) and Rezvoglar (insulin glargine-aglr).
The practical difference between them comes down to pharmacy rules. Semglee is classified as “interchangeable,” meaning a pharmacist can substitute it for Lantus without needing to call your prescriber first, similar to how generic pills work. Rezvoglar is not interchangeable, so your doctor would need to write a new prescription specifically for it. With Semglee now discontinued, the landscape of available alternatives has narrowed, which partly explains why Lantus sales have climbed.
The $35 Insulin Price Cap
If cost is part of why you’re worried about Lantus availability, the pricing landscape has shifted significantly. The Inflation Reduction Act capped out-of-pocket insulin costs at $35 per month for people on Medicare. Following that law, Sanofi, Eli Lilly, and Novo Nordisk voluntarily extended similar $35 monthly caps to most of their insulin products for broader patient populations, including many people with private insurance.
This means Lantus is more affordable now than it has been in years for most patients, which further reduces the business incentive for Sanofi to discontinue it.
If Your Pharmacy Switches You to a Different Product
Even though Lantus isn’t being discontinued, your insurance plan or pharmacy benefit manager might steer you toward a different insulin glargine product for cost reasons. If that happens, here’s what to expect.
Switching between insulin glargine products is generally done at the same dose, unit for unit. However, clinical guidelines from the UK’s NHS recommend a more cautious approach: if your blood sugar is already well controlled, your provider may reduce the starting dose of the new product by about 10% to avoid low blood sugar episodes, then adjust upward as needed. If you’ve been experiencing frequent lows, the reduction might be closer to 20%.
You’ll likely be asked to check your blood sugar more frequently for the first week or two after a switch. A follow-up review, typically within a week, lets your care team fine-tune the dose. The switch should feel seamless for most people since the active ingredient is the same, but closer monitoring catches the occasional patient who responds slightly differently to a new formulation.
International Availability
Lantus remains available in major international markets as well. In the UK, insulin glargine 100 units/mL (the Lantus concentration) is listed on NHS formularies in vial, cartridge, and SoloStar pen formats. The NHS requires insulin to be prescribed by brand name, so if your prescription says Lantus, that’s what you’ll receive. Some NHS regions have been encouraging switches to biosimilar versions for cost savings, but the original Lantus product remains an option.
The Diabetes UK tracker of insulin supply issues, which lists multiple products currently affected by shortages or discontinuations, does not include Lantus among them.