A Trial to Investigate Post Prandial Blood Glucose Control With Fast-acting Human Insulin HinsBet® Compared to Insulin Lispro (Humalog®) and Regular Human Insulin (Huminsulin® Normal) After Ingestion of a Standardized Meal in Subjects With T1DM

Inclusion Criteria: * Male or female subject aged 18-64 years (both inclusive). * Type 1 diabetes mellitus (as diagnosed clinically) \>= 12 months. * Treated with multiple daily insulin injections or CSII \>= 12 months. * Current total daily insulin treatment \< 1.2 (I)U/kg/day. * Current total daily bolus insulin treatment \< 0.7 (I)U/kg/day. * BMI 18.5-28.0 kg/m\^2 (both inclusive). * HbA1c \<= 9.0 % by local laboratory analysis * Fasting C-peptide \<= 0.30 nmol/L. Exclusion Criteria: * Known or suspected hypersensitivity to IMPs or related products. * Type 2 diabetes mellitus. * Previous participation in this trial. Participation is defined as randomised. * Participation in any clinical trial within 3 months prior to this trial. * Clinically significant abnormal haematology, coagulation, biochemistry, lipids, or urinalysis screening tests, as judged by the Investigator considering the underlying disease. * Presence of clinically significant acute gastrointestinal symptoms (e.g. nausea, vomiting, heartburn or diarrhoea), as judged by the Investigator. * Known slowing of gastric emptying and or gastrointestinal surgery that in the opinion of the Investigator might change gastrointestinal motility and food absorption. * Unusual meal habits and special diet requirements or unwillingness to eat the food provided in the trial. * Females of childbearing potential who are pregnant, breast-feeding or intend to become pregnant or are not using highly effective contraceptive methods