The blood pressure drug verapamil — a calcium channel blocker that is also used to treat angina (chest pain) and arrhythmia (irregular heart rhythm) — was shown to help preserve pancreatic beta cell function in early type 1 diabetes, according to a study published in the journal JAMA.
Preserving insulin-secreting beta cell function for as long as possible has been a major topic of type 1 diabetes research in recent years. Last year, those research efforts paid off when Tzield (teplizumab) became the first treatment approved to delay the onset of type 1 diabetes in people at high risk for the condition — with a 14-day course of the drug shown to delay a type 1 diagnosis for a median of 923 days. The drug was also shown to help preserve insulin secretion in people who were already diagnosed with type 1 diabetes. While this breakthrough drug is a vitally important tool at the moment, researchers continue to explore ways that a type 1 diagnosis can be delayed even further — with the idea that a combination of drugs may become a standard protocol at some point. Of course, an ultimate goal is to develop a treatment that prevents type 1 diabetes from developing at all in people at risk for the condition.
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For the latest study, 88 children and adolescents ages 7 to 17 with newly diagnosed type 1 diabetes were randomly assigned to take either verapamil (47 participants) or a placebo (inactive drug — 41 participants) for 52 weeks. The main part of the study took place at six different health centers throughout the United States between July 2020 and October 2021, and follow-up lasted through September 2022. The main outcome the researchers measured was C-peptide levels — this substance is secreted along with insulin by the pancreas, so it can be used to measure pancreatic insulin secretion in people who also take external insulin.
Verapamil linked to prolong pancreatic insulin secretion
Overall, 83 participants completed the study. In the verapamil group, the average C-peptide area under the curve (a measure of overall C-peptide secretion) was 0.66 pmol/ml at the beginning of the study and and 0.65 pmol/ml after 52 weeks — barely any change. In contrast, the average C-peptide area under the curve in the placebo group was 0.60 pmol/ml at the beginning of the study and 0.44 pmol/ml after 52 weeks, meaning that participants who took verapamil experienced a 30% higher C-peptide level after 52 weeks.
After 52 weeks, the proportion of participants with a peak C-peptide level of 0.2 pmol/ml or greater was 95% (41 out of 43 participants), while in the placebo group it was just 71% (27 out of 38 participants). The greater insulin secretion seen in the verapamil group translated into slightly better blood glucose control. After 52 weeks, the average A1C level (a measure of long-term blood glucose control) in the verapamil group was 6.6%, compared with 6.9% in the placebo group. The number of reported adverse events — none of which were serious — was similar in the verapamil and placebo groups.
The researchers concluded that taking verapamil may help prolong pancreatic insulin secretion in children and adolescents with newly diagnosed type 1 diabetes. Further studies are needed, they wrote, to find out how long this benefit lasts in people who take the drug and to determine the optimal length of treatment.
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