['type 2 diabetes mellitus']
['insulin glargine/lixisenatide (hoe901/ave0010)', 'insulin glargine u100 (hoe901)', 'metformin']

        Inclusion criteria :

          -  Patient with type 2 diabetes mellitus (T2DM) diagnosed for at least 1 year before the
             screening visit (V1).

          -  Patient treated with a stable, once a day basal insulin regimen (ie, type of insulin
             and time/frequency of the injection), for at least 3 months before the screening
             visit.

          -  The total daily basal insulin dose should be stable (± 20%) and <15 U/day for at least
             1 month before the screening visit.

          -  Patient receiving 1 or 2 oral anti-diabetic drugs (OADs): the OAD dose(s) must be
             stable during the 3 months before the screening visit. The OADs can be 1 to 2 out of:

          -  Metformin;

          -  Sulfonylurea (SU);

          -  Glinide;

          -  Dipeptidyl-peptidase-4 (DPP-4) inhibitor;

          -  Sodium glucose co-transporter 2 (SGLT2) inhibitor;

          -  Alpha glucosidase inhibitor (alpha-GI).

          -  Signed written informed consent.

        Exclusion criteria:

          -  Age <20 years at screening visit.

          -  HbA1c at screening visit <7.5% or >9.5%.

          -  Fasting plasma glucose (FPG) >180 mg/dL (10.0 mmol/L) at screening visit.

          -  Pregnancy or lactation, women of childbearing potential with no effective
             contraceptive method.

          -  Use of oral or injectable glucose-lowering agents other than those stated in the
             inclusion criteria in the 3 months before screening visit.

          -  Previous use of insulin regimen other than basal insulin, eg, prandial or pre-mixed
             insulin.

        Note: Short-term treatment (≤10 days) due to intercurrent illness including gestational
        diabetes is allowed at the discretion of the Investigator.

          -  Use of thiazolidinedione (TZD) within 6 months prior to screening visit.

          -  History of discontinuation of a previous treatment with a glucagon-like
             peptide-1(GLP-1) receptor agonist due to safety/ tolerability issues or lack of
             efficacy.

          -  Laboratory findings at the screening visit; including:

          -  Amylase and/or lipase >3 times the upper limit of the normal (ULN) laboratory range;

          -  Alanine aminotransferase (ALT) or aspartate aminotransferase (AST) >3 ULN;

          -  Calcitonin ≥20 pg/mL (5.9 pmol/L);

          -  Positive serum pregnancy test.

          -  Any contraindication to metformin use according to local labeling.

          -  History of hypersensitivity to any GLP-1 receptor agonist or to metacresol.

          -  Contraindication to use of insulin glargine or lixisenatide according to local
             labeling. History of hypersensitivity to insulin glargine or to any of the excipients.

          -  Personal or immediate family history of medullary thyroid cancer (MTC) or genetic
             condition that predisposes to MTC (eg, multiple endocrine neoplasia syndromes).

          -  History of pancreatitis (unless pancreatitis was related to gallstones and
             cholecystectomy has now been performed), pancreatitis during previous treatment with
             incretin therapies, chronic pancreatitis, pancreatectomy, stomach/gastric surgery.

          -  Exclusion criteria for randomization at the end of the run-in phase:

          -  HbA1c <7.5% or >9.5% at visit 6 (Week -1).

          -  Mean fasting self monitored plasma glucose (SMPG) >160 mg/dL (8.9 mmol/L), calculated
             from all available (minimum of 4 self-measurements) values during the 7 days prior to
             randomization.

        Note:fasting SMPG on the day of randomization can be included if assessed before
        randomization.

          -  Average insulin glargine daily dose ≥15 U/day or <5U/day calculated for the last 3
             days before Visit 7.

          -  Metformin total daily dose <750 mg/day.

          -  Amylase and/or lipase >3 ULN at Visit 6 (Week -1).

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