 Part A: A total of 36 patients will be enrolled in part A. Each eligible subject will participate in two 14-day treatment periods with Continuous Subcutaneous Insulin Infusion CSII of BioChaperone insulin lispro and insulin lispro Humalog, Eli Lilly and Company. Each treatment period consists of 10 treatment days under free living conditions e.g. home workplace and under standardised conditions at the clinic. Various assessments for pharmacodynamics, pharmacokinetics, pump compatibility, short-term efficacy and safety are performed on selected days, including: 