Non-obese diabetic mice were administered 150 mg/kg body weight of Cronassial daily from the 5th to the 11th week of life. Animals were killed either at the end of the treatment with Cronassial (week 11) or at week 21. The results obtained demonstrated that the appearance of the insulitis in control and treated animals at 11 and 21 weeks did not show a significant difference. The only effect of ganglioside treatment was to slow the rate of rise in glycaemia and the progression of the islet cyto-architectural derangement. In our opinion, this is not sufficient to prove the effectiveness of this drug in reducing the final diabetes incidence.