Is Once-Weekly Insulin On The Way?
There may be a new option on the horizon for current insulin users! Insulin icodec is a new insulin option currently undergoing clinical trials. The most recent trial released for insulin icodec came out in November of 2020. The trial looked at the new insulin icodec, which is a once-weekly insulin injection, with a time to peak effect of 16 hours, and a half-life of close to one week.
The trial was a randomized, double-blind, double-dummy, treat-to-target, active-controlled, parallel-group, multinational Phase 2 trial that consisted of 247 patients. The trial compared icodec with the currently most used therapy, insulin glargine (Lantus).
The trial was conducted over 26 weeks and compared the reduction in A1C levels between the two treatments. In the insulin icodec group, the average A1C in the treatment group was 8.09% compared with 7.96% in the glargine group. At the end of the trial, the trial was designed to determine how effective once-weekly insulin icodec was at reducing A1C levels, and glargine was used as a comparison point. However, the trial was not designed to detect statistical differences between the two treatment groups, so results should not be extrapolated to viewing icodec as superior or inferior to current glargine treatment. Results from the end of the trial concluded that the average A1C level in insulin icodec was 6.69%, which was a reduction of 1.33%. For the glargine group, the average A1C level was 6.87%, which was a reduction of 1.15%.
The average fasting blood glucose level was lower at all time points as well for icodec when compared with glargine. It is important to know that hypoglycemia symptoms were higher in the icodec group (53.6%) than in the glargine group (37.7%). With such a long half-life it’s uncertain when hypoglycemia symptoms are likely to occur. As providers, it would be imperative that the patient understands what hypoglycemia is, what symptoms to look for, and how to resolve it.
The author concludes in the trial that icodec has the potential to facilitate insulin management and be a first choice long-acting insulin for many people, especially those with adherence issues to daily insulin. However, there are important factors to consider when looking at this trial.
The exclusion criteria for the trial mandated that all patients be on metformin with or without being on a DPP-4 inhibitor as well. This means that other antidiabetic medications that can cause hypoglycemia such as sulfonylureas were excluded. Further studies will be needed to determine the safety and prevalence of hypoglycemia in patients on other medications that further cause hypoglycemia.
In addition, pregnant women, patients with renal impairment (EGFR <60 mL/min), unstable patients (TIA, MI, stroke), and NYHA Class IV Heart Failure patients were excluded. Further studies in these patients would also be important to determine overall safety compared to other insulins. Future studies should also implement the usage of rapid-acting insulins that are common with meals to see how that affects icodec and see if there’s any variation in the pharmacology due to the administration of other insulins.
A major point to bring up is that this trial was not powered to detect significant differences between the two treatment groups. Further studies should be powered to detect clinical differences between icodec and other mainstays insulins to determine if reductions in A1C were statistically significant or not. Icodec and glargine are supposed to be equipotent in dosing, meaning that weekly dosing is supposed to be the same between the two. However, at the end of this trial, the average daily dose of insulin was 33 U in the icodec group and 41 U in the glargine group. These results indicate that, at least in this trial, the dosing was not equipotent. This would make transitioning over to icodec potentially very difficult if there is variability in the dosing. Further studies will be needed to determine if dosing between the two groups is actually equipotent or not.
So, that is the rundown on the upcoming once-weekly insulin. What do you guys think? Is this the future of insulin therapy?
The article was written by Keith Sieling in collaboration with Eric Christianson, PharmD, BCGP, BCPS