Sanofi Toujeo SoloStar: concentrated basal insulin for adults with diabetes

Responsible: ad hoc news Lifestyle & Consumer Desk. Reviewed prior to publication on June 12, 2026 at 1:28 PM ET. Details in the imprint.

Toujeo SoloStar from Sanofi is a long-acting basal insulin designed for adults living with diabetes who need once-daily injectable insulin to help control blood sugar levels. The product contains insulin glargine at a concentration of 300 units per milliliter (U-300), making it more concentrated than traditional U-100 basal insulins and allowing a smaller injection volume for the same number of units. In the United States, Toujeo is available as prefilled disposable SoloStar and Max SoloStar pens that are typically injected once a day at the same time to support 24-hour glucose control. For many US patients, Toujeo sits alongside oral medications and other injectables as a foundational therapy that may help reduce the risk of low blood sugar events while aiming for steady fasting glucose levels.

What Toujeo SoloStar does and how it differs from other insulins

Toujeo is a next-generation formulation of insulin glargine, the same insulin analog in Sanofi's earlier product Lantus but in a three-times higher concentration, which allows Sanofi to market it as an ultra-long-acting basal insulin option. According to Sanofi's US prescribing information, Toujeo is indicated to improve glycemic control in adults with type 1 and type 2 diabetes mellitus, and in pediatric patients 6 years and older with type 1 diabetes, but it is not recommended for treating diabetic ketoacidosis. The higher concentration means that each Toujeo SoloStar pen delivers up to 450 units, while the Max SoloStar pen can deliver up to 900 units per prefilled pen, which can be particularly useful for people who require higher daily insulin doses. Clinical data cited by Sanofi show that Toujeo reaches its steady-state effect after several days of once-daily dosing and maintains blood glucose coverage for up to 36 hours in some users, offering a flatter and more prolonged action profile than many older basal insulins.

Because of this pharmacologic profile, Toujeo is generally started once daily at a dose tailored to the patient’s prior insulin usage and weight, with adjustments every few days based on fasting blood sugar readings. Sanofi's educational materials emphasize that Toujeo must not be diluted or mixed with other insulins and that it should be administered subcutaneously in the abdomen, thigh, or upper arm using the pen’s fine needle and dialed dose mechanism. The SoloStar pen is designed to deliver doses in 1-unit increments up to 80 units per injection, while the Max SoloStar pen can deliver up to 160 units in a single injection through its dial, which is aimed at simplifying treatment for patients with insulin resistance who need larger doses. The device design builds on Sanofi's long-running SoloStar platform that focuses on ease of use, compact size, and relatively low injection force to support patient adherence, especially for those self-injecting at home.

In multiple large clinical studies comparing Toujeo with Lantus, Sanofi reports that Toujeo achieved similar reductions in HbA1c, a key marker of long-term blood sugar control, while showing a lower rate of nocturnal hypoglycemia in some adult patient groups. For example, pooled analyses of the EDITION trial program showed fewer confirmed or severe nighttime hypoglycemic events in adults with type 2 diabetes treated with Toujeo than in those on Lantus, with differences most notable in insulin-experienced patients starting or adjusting basal therapy. While individual results vary, Sanofi uses this data point to position Toujeo as a basal insulin choice for patients and physicians who are particularly concerned about overnight lows and the impact of hypoglycemia on quality of life. The medication remains a prescription-only therapy and is typically part of a broader diabetes management plan that includes diet, exercise, and sometimes additional non-insulin medications such as GLP-1 receptor agonists or SGLT2 inhibitors.

Sanofi’s official Toujeo information for US patients emphasizes safety considerations, including the risk of hypoglycemia, potential allergic reactions, and injection site reactions, all of which are class-wide concerns for insulin products. Patients are advised to regularly monitor their blood glucose, particularly when starting Toujeo or adjusting the dose, and to speak with their healthcare provider about any vision changes, signs of fluid retention, or sudden weight gain, which can be associated with insulin therapy. Toujeo should be stored in the refrigerator before first use and then kept at room temperature once in use, with each pen typically discarded after a set number of days, which Sanofi specifies in the US packaging information. As with other insulin pens, users in the United States can obtain Toujeo only by prescription, and pharmacies may dispense either the SoloStar or Max SoloStar format depending on the physician’s instructions and patient needs.

From a pricing perspective, public sources indicate that the list price for a box of three Toujeo SoloStar pens in the US is several hundred dollars, though the net cost to patients is often lower due to insurance coverage, manufacturer savings programs, and pharmacy discount cards. Sanofi runs a savings program for eligible commercially insured US patients that can significantly reduce out-of-pocket costs, subject to specific terms, caps, and eligibility criteria, and details are outlined on the US Toujeo patient support site. Because coverage and copay structures vary widely, people considering Toujeo in the United States typically check their plan’s formulary status and tier placement, as some insurers require prior authorization or step therapy compared with other basal insulin options. For uninsured or underinsured patients, third-party discount programs and some patient assistance foundations may help reduce the cost, though availability and criteria differ across states.

In the US market, Toujeo competes in a crowded basal insulin segment that includes insulin glargine biosimilars and other long-acting analogs such as insulin degludec, so prescribers weigh factors like duration of action, hypoglycemia data, dosing flexibility, and payer coverage when choosing among options. Sanofi continues to highlight Toujeo’s U-300 formulation and device platform as differentiators, particularly for adults who need high daily doses or want a steady profile with a once-daily routine. Despite the rise of newer glucose-lowering medications, basal insulin remains a mainstay for many Americans with long-standing type 2 diabetes, and Toujeo occupies a central place in Sanofi’s US diabetes portfolio alongside other treatments such as rapid-acting insulins and combination products. From an organizational standpoint, Toujeo contributes to Sanofi’s general medicines business, which includes its diabetes and cardiovascular portfolio, a segment that still generates substantial revenue even as the company invests heavily in immunology and specialty care.

For shoppers, it makes sense to discuss with a healthcare professional whether Toujeo’s once-daily dosing, concentrated formulation, and pen design align with their diabetes management needs, particularly if they are already using another basal insulin and considering a switch. Toujeo continues to serve as one of Sanofi’s key established medicines in diabetes, anchoring its presence in this chronic disease area while the company rebalances its research and development pipeline. Shares of Sanofi (FR0000120578, ticker SNY) traded at $44.06 on Nasdaq in premarket trading on June 12, 2026, according to recent market data.

This article was created with a.i. assistance and editorially reviewed. Product information is provided without warranty; prices and availability may change at any time. Not investment advice, not a buy or sell recommendation. Trading in securities carries risks up to the total loss of capital.