HOSPITAL PRACTICE

New easy-to-use insulin device should improve compliance

It's tough to manage diabetes. As if dealing with multiple medications, diet, and exercise weren't enough, insulin therapy can be especially challenging. Patients not only struggle with when to take their insulin, they have to accurately measure a dose and correctly inject it—no small feat for a patient with impaired vision or diminished dexterity. But the imminent launch of InnoLet (Novo Nordisk) offers an alternate means to address these difficulties.

Approved in December 2001, InnoLet will hit the market shortly. This prefilled insulin device features a large dial, not unlike a kitchen timer. It enables individuals to "dial" and audibly "click in" the insulin dose. The large grip and ergonomic design help make the device easy and comfortable to hold, providing stability during injection for better control over injection depth and decreased tremor or movement at the needle tip. Like an insulin pen, InnoLet provides diabetes patients an alternative to the traditional syringe-and-vial insulin delivery system. InnoLet uses replaceable needles and insulin cartridges.

Lisa Kroon, Pharm.D., CDE, assistant clinical professor, department of clinical pharmacy, University of California, San Francisco, noted that the main advantage to InnoLet is that it "can help decrease potential errors in dosing of the insulin. Any person is going to find it easy to use." Kroon predicts InnoLet will be especially appealing for people with the vision or dexterity problems common to many individuals with Type 2 diabetes.

The inaccuracy of insulin dosing via syringe and vial has appeared sporadically in professional literature since 1981. One study showed a percentage of error in self-administered doses that ranged from 5.8% to 19.3%, with the highest percentage of error occurring in individuals aged 40 or older. Another study estimated that dosing errors of 15% or more occur in as many as 24% of self-administered doses in individuals aged 60 or older. Studies such as these—in conjunction with adverse effects attributable to improper insulin dose—and studies about long-term diabetes complications emphasize the need for improvement in insulin use.

To determine InnoLet's effect on dose accuracy and ease of use, a multicenter British study compared the device with the Humulin Insulin Pen (Lilly) or a syringe. The 86 participants in the study were visually impaired and had not previously used insulin. During one phase, individuals attempted to set and inject a dose without any previous instruction. Of those using InnoLet, 84% correctly set and dispensed an insulin dose in 26 seconds. (Doses were discarded rather than injected.) In comparison, only 31% of participants were able to set and dispense a dose in 53 seconds using the traditional syringe; 41% of individuals using the Humulin Pen dispensed a correct dose in 65 seconds. The percentage of patients able to accurately set a dose, and the time required, was significantly better for patients using InnoLet than for those using the syringe or the insulin pen.

Following verbal instructions and a demonstration, patients who had not successfully set and dispensed three doses were reevaluated: 100% of those using InnoLet set their doses correctly, compared with 68% using Humulin Pen and 50% using a syringe. According to patient questionnaires, 87% of patients in this study preferred InnoLet to other delivery systems.

Kroon commented, "The accuracy [of insulin dose] is important, but as important is compliance or adherence with the diabetes regimen. The InnoLet device can really assist in that."

InnoLet's design makes it easy to use, Kroon explained. "The mechanism to deliver the dose is very easy to push. It's a larger mechanism than that of the syringe, so the patients found it easier to hold while injecting. For people with any kind of dexterity—for example, arthritis—this device would be well suited."

Although insulin pens and devices are more widely used than syringes in Japan and most of Europe, lack of reimbursement has limited the use of alternative delivery systems in the United States. However, Kroon anticipates "that patients are going to like InnoLet so much that they may be willing to pay out of pocket for it, depending on its cost when it becomes available." Her experience in the diabetes clinic has convinced her that "people with diabetes want a system that's going to allow them flexibility, discreetness, and portability," and she sees these advantages with InnoLet and other alternative delivery systems.

According to the manufacturer, InnoLet should reach pharmacies later this year. It will be available without prescription with both Novolin 70/30 (Novo Nordisk) and Novolin N (Novo Nordisk). At press time, pricing had not been determined.

Kathy Hitchens, Pharm.D.

The author is a clinical writer in the Indianapolis area.

Kathy Hitchens. New easy-to-use insulin device should improve compliance.

Drug Topics

2002;9:52.