Participants will receive once weekly s.c. injections of placebo equivalent to insulin 287.

Metformin is considered as non investigational medicinal product. Subject will continue metformin at stable pre-trial dose.

Dipeptidyl peptidase-4 inhibitors are considered as non investigational medicinal products. Subject will continue dipeptidyl peptidase-4 inhibitor at stable pre-trial dose.

Insulin glargine (100 U/mL) once daily s.c. injections at the starting dose of 10 units. Dose adjustment will be done for the individual patient based on the three pre-breakfast self-measured plasma glucose values measured on two days prior to titration and on the day of the contact. The insulin dose adjustment should aim to reach an SMPG of 3.9-6.0 mmol/L (70-108 mg/dL).

Participants will receive once daily s.c. injections of placebo equivalent to insulin glargine.

Participants measured their plasma glucose (PG) levels using blood glucose meters (as plasma equivalent values of capillary whole blood glucose) at 9 time points (before breakfast, 90 minutes after the start of breakfast, before lunch, 90 minutes after the start of lunch, before dinner, 90 minutes after the start of dinner, at bedtime, at 4 am, before breakfast the following day). 9-point SMPG values after 26 weeks are presented. The endpoint was evaluated based on the data from on-treatment without ancillary treatment period, starting at the date of first dose of trial product until the follow-up visit, or the last date on trial product + 5 weeks for once daily insulin and + 6 weeks for once weekly insulin, or initiation of any diabetes treatment other than trial products and metformin +/- DPP4i, or increase of the dose of metformin or DPP4i.

Participants measured their PG levels using blood glucose meters at 9 time points (before breakfast, 90 minutes after the start of breakfast, before lunch, 90 minutes after the start of lunch, before dinner, 90 minutes after the start of dinner, at bedtime, at 4 am, before breakfast the following day). The endpoint was evaluated based on the data from on-treatment without ancillary treatment period, starting at the date of first dose of trial product until the follow-up visit, or the last date on trial product + 5 weeks for once daily insulin and + 6 weeks for once weekly insulin, or initiation of any diabetes treatment other than trial products and metformin +/- DPP4i, or increase of the dose of metformin or DPP4i.

Participants measured their plasma glucose (PG) levels using blood glucose meters at 9 time points (before breakfast, 90 minutes after the start of breakfast, before lunch, 90 minutes after the start of lunch, before dinner, 90 minutes after the start of dinner, at bedtime, at 4 am, before breakfast the following day). Presented fluctuation in 9-point SMPG profile is the integrated absolute distance from the mean profile value divided by measurement time and is calculated using the trapezoidal method. The endpoint was evaluated based on the data from on-treatment without ancillary treatment period, starting at the date of first dose of trial product until the follow-up visit, or the last date on trial product + 5 weeks for once daily insulin and + 6 weeks for once weekly insulin, or initiation of any diabetes treatment other than trial products and metformin +/- DPP4i, or increase of the dose of metformin or DPP4i.

Fasting C-peptide at week 26 is presented. The endpoint was evaluated based on the data from on-treatment without ancillary treatment period, starting at the date of first dose of trial product until the follow-up visit, or the last date on trial product + 5 weeks for once daily insulin and + 6 weeks for once weekly insulin, or initiation of any diabetes treatment other than trial products and metformin +/- DPP4i, or increase of the dose of metformin or DPP4i.

Change in body weight from baseline (week 0) to week 26 is presented. The endpoint was evaluated based on the data from on-treatment without ancillary treatment period, starting at the date of first dose of trial product until the follow-up visit, or the last date on trial product + 5 weeks for once daily insulin and + 6 weeks for once weekly insulin, or initiation of any diabetes treatment other than trial products and metformin +/- DPP4i, or increase of the dose of metformin or DPP4i.

Weekly dose of insulin 287 and weekly dose of glargine at week 25 and week 26 are presented.The endpoint was evaluated based on the data from on-treatment without ancillary treatment period, starting at the date of first dose of trial product until the follow-up visit, or the last date on trial product + 5 weeks for once daily insulin and + 6 weeks for once weekly insulin, or initiation of any diabetes treatment other than trial products and metformin +/- DPP4i, or increase of the dose of metformin or DPP4i.

An adverse event (AE) is any untoward medical occurrence in a clinical trial subject administered or using a medicinal product, whether or not considered related to the medicinal product or usage. A TEAE was defined as an event that had onset date (or increase in severity) during the on-treatment observation period. The endpoint was evaluated based on the data from on-treatment period, starting at the date of first dose of trial product, and ending at follow-up visit, or the last date on trial product + 5 weeks for once daily insulin and + 6 weeks for once weekly insulin.

Hypoglycaemia alert value (level 1) was defined as episodes that were sufficiently low for treatment with fast-acting carbohydrate and dose adjustment of glucose-lowering therapy with plasma glucose value of equal to or above (>=) 3.0 and less than (<) 3.9 mmol/L (>= 54 and < 70 mg/dL) confirmed by BG meter. Number of hypoglycaemic alert episodes (level 1) that occurred from week 0 to week 26 are presented.

Clinically significant hypoglycaemic episodes (level 2) were defined as episodes that were sufficiently low to indicate serious, clinically important hypoglycaemia with plasma glucose value of less than (<) 3.0 mmol/L (54 mg/dL). Severe hypoglycaemic episodes (level 3) were defined as episodes that were associated with severe cognitive impairment requiring external assistance for recovery. Number of clinically significant hypoglycaemic episodes (level 2), confirmed by blood glucose (BG) meter or severe hypoglycaemic episodes (level 3) that occurred from week 0 to week 26 are presented.

Severe hypoglycaemic episodes (level 3) were defined as episodes that were associated with severe cognitive impairment requiring external assistance for recovery. Number of severe hypoglycaemic episodes that occurred from week 0 to week 26 are presented.

Samples from the insulin 287 arm of the study were analysed for anti-insulin 287 antibodies. Confirmed anti-insulin 287 antibody positive samples had an antibody titre value determined. The endpoint was evaluated based on the data from in-trial period, starting at randomisation, and ending at the last direct participant-site contact, or when participant withdrew their informed consent, or the last participant-investigator contact for participants lost to follow-up, or death.

Anti-insulin 287 or glargine antibodies were classified as negative if % B/T was below a certain cut point. Samples positive for anti-insulin 287 or glargine antibodies were further tested for cross-reactivity to endogenous insulin. Samples not further tested are categorised as not applicable (NA). Unknown refers to samples with insufficient volume to perform analysis. The endpoint was evaluated based on the data from in-trial period, starting at randomisation, and ending at the last direct participant-site contact, or when participant withdrew their informed consent, or the last participant-investigator contact for participants lost to follow-up, or death.

Change in anti-insulin 287 antibodies level is not assessed because change in anti-insulin 287 antibody titres is a more meaningful way of describing the change in antibody levels. The results for change in anti-insulin 287 antibody titres are reported as a separate endpoint.

Participants were to receive once daily s.c injection of Insulin glargine using 10 ml vial and syringe at a starting dose of 10 U and once weekly placebo for 26 weeks. The insulin dose was then adjusted to reach the glycaemic target of 3.9-6.0 mmol/L based on 3 pre-breakfast SMPG values measured on 2 previous days and on the day of the titration. If at least one pre-breakfast SMPG value was: < 3.0 mmol/L- dose reduced by 4 U, and 3.0-3.8 dose reduced by 2 U. Otherwise, the dose adjustment was based on the mean of SMPG values. If the mean was: 3.9-6.0 mmol/L- no adjustment; 6.1-7.0 mmol/L- dose increased by 2 U, and >7.0 mmol/L- dose increased by 4 U. All participants used metformin with or without DPP4i at the stable, pre-trial dose and at the same frequency unless due to safety concerns.

Participants were to receive once daily s.c injection of Insulin glargine using 10 ml vial and syringe at a starting dose of 10 U and once weekly placebo for 26 weeks. The insulin dose was then adjusted to reach the glycaemic target of 3.9-6.0 mmol/L based on 3 pre-breakfast SMPG values measured on 2 previous days and on the day of the titration. If at least one pre-breakfast SMPG value was: < 3.0 mmol/L- dose reduced by 4 U, and 3.0-3.8 dose reduced by 2 U. Otherwise, the dose adjustment was based on the mean of SMPG values. If the mean was: 3.9-6.0 mmol/L- no adjustment; 6.1-7.0 mmol/L- dose increased by 2 U, and >7.0 mmol/L- dose increased by 4 U. All participants used metformin with or without DPP4i at the stable, pre-trial dose and at the same frequency unless due to safety concerns.

Participants were to receive once daily s.c injection of Insulin glargine using 10 ml vial and syringe at a starting dose of 10 U and once weekly placebo for 26 weeks. The insulin dose was then adjusted to reach the glycaemic target of 3.9-6.0 mmol/L based on 3 pre-breakfast SMPG values measured on 2 previous days and on the day of the titration. If at least one pre-breakfast SMPG value was: < 3.0 mmol/L- dose reduced by 4 U, and 3.0-3.8 dose reduced by 2 U. Otherwise, the dose adjustment was based on the mean of SMPG values. If the mean was: 3.9-6.0 mmol/L- no adjustment; 6.1-7.0 mmol/L- dose increased by 2 U, and >7.0 mmol/L- dose increased by 4 U. All participants used metformin with or without DPP4i at the stable, pre-trial dose and at the same frequency unless due to safety concerns.

Participants were to receive once daily s.c injection of Insulin glargine using 10 ml vial and syringe at a starting dose of 10 U and once weekly placebo for 26 weeks. The insulin dose was then adjusted to reach the glycaemic target of 3.9-6.0 mmol/L based on 3 pre-breakfast SMPG values measured on 2 previous days and on the day of the titration. If at least one pre-breakfast SMPG value was: < 3.0 mmol/L- dose reduced by 4 U, and 3.0-3.8 dose reduced by 2 U. Otherwise, the dose adjustment was based on the mean of SMPG values. If the mean was: 3.9-6.0 mmol/L- no adjustment; 6.1-7.0 mmol/L- dose increased by 2 U, and >7.0 mmol/L- dose increased by 4 U. All participants used metformin with or without DPP4i at the stable, pre-trial dose and at the same frequency unless due to safety concerns.

Participants were to receive once daily s.c injection of Insulin glargine using 10 ml vial and syringe at a starting dose of 10 U and once weekly placebo for 26 weeks. The insulin dose was then adjusted to reach the glycaemic target of 3.9-6.0 mmol/L based on 3 pre-breakfast SMPG values measured on 2 previous days and on the day of the titration. If at least one pre-breakfast SMPG value was: < 3.0 mmol/L- dose reduced by 4 U, and 3.0-3.8 dose reduced by 2 U. Otherwise, the dose adjustment was based on the mean of SMPG values. If the mean was: 3.9-6.0 mmol/L- no adjustment; 6.1-7.0 mmol/L- dose increased by 2 U, and >7.0 mmol/L- dose increased by 4 U. All participants used metformin with or without DPP4i at the stable, pre-trial dose and at the same frequency unless due to safety concerns.

Participants were to receive once daily s.c injection of Insulin glargine using 10 ml vial and syringe at a starting dose of 10 U and once weekly placebo for 26 weeks. The insulin dose was then adjusted to reach the glycaemic target of 3.9-6.0 mmol/L based on 3 pre-breakfast SMPG values measured on 2 previous days and on the day of the titration. If at least one pre-breakfast SMPG value was: < 3.0 mmol/L- dose reduced by 4 U, and 3.0-3.8 dose reduced by 2 U. Otherwise, the dose adjustment was based on the mean of SMPG values. If the mean was: 3.9-6.0 mmol/L- no adjustment; 6.1-7.0 mmol/L- dose increased by 2 U, and >7.0 mmol/L- dose increased by 4 U. All participants used metformin with or without DPP4i at the stable, pre-trial dose and at the same frequency unless due to safety concerns.

Participants were to receive once daily s.c injection of Insulin glargine using 10 ml vial and syringe at a starting dose of 10 U and once weekly placebo for 26 weeks. The insulin dose was then adjusted to reach the glycaemic target of 3.9-6.0 mmol/L based on 3 pre-breakfast SMPG values measured on 2 previous days and on the day of the titration. If at least one pre-breakfast SMPG value was: < 3.0 mmol/L- dose reduced by 4 U, and 3.0-3.8 dose reduced by 2 U. Otherwise, the dose adjustment was based on the mean of SMPG values. If the mean was: 3.9-6.0 mmol/L- no adjustment; 6.1-7.0 mmol/L- dose increased by 2 U, and >7.0 mmol/L- dose increased by 4 U. All participants used metformin with or without DPP4i at the stable, pre-trial dose and at the same frequency unless due to safety concerns.

Participants were to receive once daily s.c injection of Insulin glargine using 10 ml vial and syringe at a starting dose of 10 U and once weekly placebo for 26 weeks. The insulin dose was then adjusted to reach the glycaemic target of 3.9-6.0 mmol/L based on 3 pre-breakfast SMPG values measured on 2 previous days and on the day of the titration. If at least one pre-breakfast SMPG value was: < 3.0 mmol/L- dose reduced by 4 U, and 3.0-3.8 dose reduced by 2 U. Otherwise, the dose adjustment was based on the mean of SMPG values. If the mean was: 3.9-6.0 mmol/L- no adjustment; 6.1-7.0 mmol/L- dose increased by 2 U, and >7.0 mmol/L- dose increased by 4 U. All participants used metformin with or without DPP4i at the stable, pre-trial dose and at the same frequency unless due to safety concerns.

Participants were to receive once daily s.c injection of Insulin glargine using 10 ml vial and syringe at a starting dose of 10 U and once weekly placebo for 26 weeks. The insulin dose was then adjusted to reach the glycaemic target of 3.9-6.0 mmol/L based on 3 pre-breakfast SMPG values measured on 2 previous days and on the day of the titration. If at least one pre-breakfast SMPG value was: < 3.0 mmol/L- dose reduced by 4 U, and 3.0-3.8 dose reduced by 2 U. Otherwise, the dose adjustment was based on the mean of SMPG values. If the mean was: 3.9-6.0 mmol/L- no adjustment; 6.1-7.0 mmol/L- dose increased by 2 U, and >7.0 mmol/L- dose increased by 4 U. All participants used metformin with or without DPP4i at the stable, pre-trial dose and at the same frequency unless due to safety concerns.

Participants were to receive once daily s.c injection of Insulin glargine using 10 ml vial and syringe at a starting dose of 10 U and once weekly placebo for 26 weeks. The insulin dose was then adjusted to reach the glycaemic target of 3.9-6.0 mmol/L based on 3 pre-breakfast SMPG values measured on 2 previous days and on the day of the titration. If at least one pre-breakfast SMPG value was: < 3.0 mmol/L- dose reduced by 4 U, and 3.0-3.8 dose reduced by 2 U. Otherwise, the dose adjustment was based on the mean of SMPG values. If the mean was: 3.9-6.0 mmol/L- no adjustment; 6.1-7.0 mmol/L- dose increased by 2 U, and >7.0 mmol/L- dose increased by 4 U. All participants used metformin with or without DPP4i at the stable, pre-trial dose and at the same frequency unless due to safety concerns.

Participants were to receive once daily s.c injection of Insulin glargine using 10 ml vial and syringe at a starting dose of 10 U and once weekly placebo for 26 weeks. The insulin dose was then adjusted to reach the glycaemic target of 3.9-6.0 mmol/L based on 3 pre-breakfast SMPG values measured on 2 previous days and on the day of the titration. If at least one pre-breakfast SMPG value was: < 3.0 mmol/L- dose reduced by 4 U, and 3.0-3.8 dose reduced by 2 U. Otherwise, the dose adjustment was based on the mean of SMPG values. If the mean was: 3.9-6.0 mmol/L- no adjustment; 6.1-7.0 mmol/L- dose increased by 2 U, and >7.0 mmol/L- dose increased by 4 U. All participants used metformin with or without DPP4i at the stable, pre-trial dose and at the same frequency unless due to safety concerns.