This clinical trial is focused on studying the effects of a medication called Verapamil SR on individuals diagnosed with Type 1 diabetes mellitus. Type 1 diabetes is a condition where the body does not produce insulin, a hormone needed to allow sugar (glucose) to enter cells to produce energy. The medication being tested, Verapamil SR, is a type of drug known as a calcium channel blocker, which is commonly used to treat high blood pressure and heart-related conditions. In this study, it is being explored for its potential to help preserve the function of beta cells in the pancreas, which are responsible for producing insulin.

The purpose of the study is to observe how Verapamil SR affects the preservation of beta-cell function over a long period. Participants in the study will take 360 mg of Verapamil SR orally once a day. The study will last for 24 months, during which participants will have their beta-cell function measured at the start and at the end of the study. This will be done using a test called the mixed-meal tolerance test (MMTT), which helps assess how well the body is producing insulin. Some participants may have previously been treated with either a placebo or Verapamil SR for 12 months in a prior study.

Throughout the study, changes in blood glucose control, insulin requirements, and any severe low blood sugar episodes will be monitored. Additionally, the study will track any adverse events or changes in vital signs, such as heart rate and blood pressure, to ensure the safety of the participants. The study aims to provide valuable insights into whether Verapamil SR can help maintain insulin production in people with Type 1 diabetes, potentially leading to better management of the condition.