en Endocrinology Endocrinology Original Article Original Article <span style="font-size:14px;"><span style="font-family:Times New Roman;"><span style="line-height:150%"><span style="color:#0033ff;"><em><b><span style="line-height:150%">Background:</span></b></em></span> <span style="line-height:150%">T1DM is an autoimmune and chronic metabolic disorder characterized by the destruction of pancreatic beta cells. The Bacillus Calmette&ndash;Gu&eacute;rin (BCG) vaccine, originally used for tuberculosis prevention, has shown potential in modulating the immune response and improving beta-cell function. This study aimed to evaluate the therapeutic effects of two doses of BCG vaccine, administered four weeks apart, on glycemic control and selected immunological markers in patients with T1DM.<span style="font-family:&quot;Times New Roman&quot;,serif"></span></span></span><br> <span style="line-height:150%"><span style="color:#0033ff;"><em><b><span style="line-height:150%">Methods:</span></b></em></span> <span style="line-height:150%">In this single-center, double-blind randomized clinical trial, 33 patients with T1DM were enrolled and randomly assigned to intervention and control groups in a 1:1 ratio, matched by age and sex. The intervention group received two intradermal doses of the BCG vaccine, with a four-week interval. Fasting blood samples were collected at baseline and during follow-up to assess biochemical and immunological parameters. Patients were followed for 18 months. </span></span><br> <span style="line-height:150%"><em><span style="color:#0033ff;"><b><span style="line-height:150%">Results:</span></b></span></em><span style="line-height:150%"><em><span style="color:#0033ff;"> </span></em>The mean age of participants was 11.25 &plusmn; 3.32 years in the control group and 10.69 &plusmn; 3.22 years in the BCG group. Anti-ICA levels significantly decreased in the BCG group by the end of the follow-up period. Although there was no significant difference in fasting blood glucose levels between the two groups, a significant reduction in HbA1c was observed in the BCG group after 18 months.</span></span><br> <span style="line-height:150%"><span style="color:#0033ff;"><em><b><span style="line-height:150%">Conclusion:</span></b></em></span> <span style="line-height:150%">The findings suggest that BCG vaccination may contribute to improved long-term glycemic control, as evidenced by reduced HbA1c levels, in patients with T1DM. Additionally, the decrease in Anti-ICA levels indicates a potential immunomodulatory effect, supporting the therapeutic promise of BCG in autoimmune diabetes.</span></span></span></span><br> &nbsp; Diabetes, Type 1 diabetes, BCG vaccine, HbA1c, Iran 7 0 http://caspjim.com/browse.php?a_code=A-10-3669-1&slc_lang=en&sid=1 Mahtab Ordoei dr.ordouei1976@gmail.com 100319475328460056336 100319475328460056336 No Yazd diabetes research center, Shahid Sadoughi University of Medical Sciences, Yazd, Iran Nasrin Behniafard n_behniafard@yahoo.com 100319475328460056337 100319475328460056337 No Yazd diabetes research center, Shahid Sadoughi University of Medical Sciences, Yazd, Iran Nasim Namiranian namiranian.nasim@gmail.com 100319475328460056338 100319475328460056338 No Yazd diabetes research center, Shahid Sadoughi University of Medical Sciences, Yazd, Iran Samira Asadollahi sasadullahi@yahoo.com 100319475328460056339 100319475328460056339 No Yazd diabetes research center, Shahid Sadoughi University of Medical Sciences, Yazd, Iran Saeede Jam- Ashkezari saeedehjam@yahoo.com 100319475328460056340 100319475328460056340 No Yazd diabetes research center, Shahid Sadoughi University of Medical Sciences, Yazd, Iran Roghaye Razavi forough.nutritionist@gmail.com 100319475328460056341 100319475328460056341 Yes Yazd diabetes research center, Shahid Sadoughi University of Medical Sciences, Yazd, Iran