A Trial to Compare BioChaperone Insulin Lispro Formulations With US Approved Humalog® and With EU Approved Humalog® in Patients With Type 1 Diabetes Mellitus

Inclusion Criteria: * Subjects with type 1 Diabetes Mellitus * Body Mass Index (BMI) between 18.5 and 28.5 kg/m\^2, both inclusive * HbA1c \<= 75 mmol/mol (\<=9.0%). * Fasting negative C-peptide (\<= 0.30 nmol/L). * Total insulin dose of \< 1.2 (I)U/kg/day. * Stable insulin regimen (with respect to safety of the subject and scientific integrity of the study) using continuous subcutaneous insulin infusion (CSII) or multiple daily insulin injections (MDI) for at least 2 months. Exclusion Criteria: * Known or suspected hypersensitivity to IMP(s) or related products. * Receipt of any medicinal product in clinical development within 30 days or at least 5 half-lives of the related substances and their metabolites (whichever is longer) before randomisation in this trial. * History of multiple and/or severe allergies to drugs or foods or a history of severe anaphylactic reaction. * Any history or presence of cancer except basal cell skin cancer or squamous cell skin cancer as judged by the Investigator. * Any history or presence of clinically relevant comorbidity capable of constituting a risk for the subject when participating in the trial or of interfering with the interpretation of data. * Signs of acute illness as judged by the Investigator. * Any serious systemic infectious disease during four weeks prior to first dosing of the trial drug, as judged by the Investigator. * Clinically significant abnormal screening laboratory tests, as judged by the Investigator. * Proliferative retinopathy or maculopathy as judged by the Investigator based on a recent (\<1.5 years) ophthalmologic examination. * Use of oral antidiabetic drugs (OADs) and/or GLP-1 receptor agonists within 3 months prior to screening.