Primary Objective:

To demonstrate the ease of use of the U300 pen injector in pen-naïve and insulin-naïve type 2 diabetes mellitus (T2DM) patients in a 4-week once-daily dosing regimen with HOE901-U300.

Secondary Objectives:

To assess in a 4-week once-daily dosing regimen with HOE901-U300 in pen-naïve and insulin-naïve T2DM patients.

The safety and usability of the U300 pen injector. The glycemic control with the U300 pen injector. The safety of HOE901-U300.

The total study duration for a participants can be approximately up to 10 weeks.

Inclusion criteria:

• Patients with T2DM inadequately controlled with non-insulin, non-injectable anti-hyperglycemic drug(s) and for whom the Investigator/treating physicians has decided that basal insulin is appropriate.
• Signed written informed consent.

Exclusion criteria:

• Glycated hemoglobin A1c (HbA1c) <7.0% (<53 mmol/mol) or >11% (97 mmol/mol) at screening.
• Age <18 years at the time of screening.
• Body Mass Index (BMI) >40 kg/m2.
• Diabetes other than T2DM.
• History of T2DM for less than 1 year before screening.
• Less than 6 months anti-hyperglycemic treatment before screening.
• Initiation of new glucose-lowering medications and/or weight loss drug in the last 3 months before screening visit.
• Previous treatment with Glucagon Like Peptide-1 (GLP-1) agonist.
• Patients receiving only non-insulin anti-hyperglycemic drugs not approved for combination with insulin according to local labeling/local treatment guidelines and/or sulfonylurea or glinides.
• Current or previous insulin use except for a maximum of 8 consecutive days and a total of 14 days (eg, acute illness, surgery) during the last year prior to screening.
• Any contraindication to insulin glargine (Lantus) according to the National Product labeling or any excipients.
• Any contraindication to the mandatory background non-insulin anti-hyperglycemic medication according to the respective National Product labeling.
• Latest eye examination by an ophthalmologist >12 months prior to inclusion.
• More than one episode of severe hypoglycemia with seizure, coma or requiring assistance of another person during the past 6 months.
• Unstable proliferative diabetic retinopathy or any other rapidly progressive diabetic retinopathy or macular edema likely to require treatment (eg, laser, surgical treatment or injectable drugs) during the study period.

The above information is not intended to contain all considerations relevant to a patient's potential participation in a clinical trial.