Once-Weekly Basal Insulin: A Narrative Review of What Changes for Patients When Injections Fall from Daily to Weekly
DOI:
https://doi.org/10.5281/zenodo.22238835Keywords:
Once-weekly insulin, Insulin icodec, Insulin efsitora alfa, Hypoglycaemia, Treatment satisfactionAbstract
Basal insulin given once a week rather than once a day reduces injections from 365 a year to 52, and two such insulins have
completed phase 3 testing. In type 2 diabetes the results are favourable: across five trials, once-weekly icodec was superior or
non-inferior to daily comparators for HbA1c reduction with similar rates of clinically significant or severe hypoglycaemia. In type
1 diabetes the picture differs. Both published phase 3 trials found non-inferior glycaemic control alongside significantly higher
rates of combined level 2 or level 3 hypoglycaemia, and one reported a greater incidence of severe hypoglycaemia. Less widely
noted, treatment satisfaction scores in the type 1 icodec trial favoured the daily regimen, with an estimated treatment difference of
-1.09 (95% CI -1.85 to -0.34, p = 0.0044), so fewer injections did not translate into a more satisfied patient. This review sets out
the trial evidence by diabetes type, the pharmacological reason the two differ, and what a half-life measured in weeks means when
a dose is wrong.
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