Study: NCT01760447

Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: Sitagliptin plus metformin
Description: Participants received 2 tablets daily, one taken with a morning meal and one taken with an evening meal, to provide a total daily dose of 100 mg of sitagliptin and 1000 mg, 1700 mg or 2000 mg of metformin. Dosage of metformin was based on each participant's daily metformin dose prior to enrollment.

Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: Placebo to metformin
Description: Participants received 2 tablets daily, one taken with a morning meal and one taken with an evening meal. Each tablet contained placebo to metformin.

Intervention type: DRUG
Group type: PLACEBO_COMPARATOR
Intervention: Metformin
Description: Participants received 2 tablets daily, one taken with a morning meal and one taken with an evening meal, to provide a total daily dose of 1000 mg, 1700 mg or 2000 mg of metformin. Dosage was based on each participant's daily metformin dose prior to enrollment.

Intervention type: DRUG
Group type: PLACEBO_COMPARATOR
Intervention: Placebo to sitagliptin plus metformin
Description: Participants received 2 tablets daily, one taken with a morning meal and one taken with an evening meal. Each tablet contained placebo to sitagliptin plus metformin.

Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: Sitagliptin plus metformin XR
Description: Participants received 2 tablets daily, both taken together with a meal, to provide a total daily dose of 100 mg of sitagliptin and 1000 mg, 1500 mg or 2000 mg of metformin. Dosage of metformin XR was based on each participant's daily metformin dose prior to enrollment.

Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: Placebo to metformin XR
Description: Participants received 2 tablets daily, both taken together with a meal. Each tablet contained placebo to metformin XR.

Intervention type: DRUG
Group type: PLACEBO_COMPARATOR
Intervention: Insulin
Description: Participants who met protocol-specific glycemic rescue criteria received insulin as glycemic rescue therapy; participants on background insulin had their insulin dose increased for glycemic rescue. During Weeks 20-54, for participants who were not on background insulin or rescued with insulin during Weeks 0-20 in the Sitagliptin/Metformin and Metformin arms (protocol MK-0431A-170), and during Weeks 0-54 for participants not on background insulin in the Sitagliptin/Metformin XR and Metformin XR arms (protocol MK-0431A-289), the type of insulin for glycemic rescue was specified to be insulin glargine.

Intervention type: DRUG
Group type: PLACEBO_COMPARATOR
Intervention: Insulin
Description: Participants who met protocol-specific glycemic rescue criteria received insulin as glycemic rescue therapy; participants on background insulin had their insulin dose increased for glycemic rescue. During Weeks 20-54, for participants who were not on background insulin or rescued with insulin during Weeks 0-20 in the Sitagliptin/Metformin and Metformin arms (protocol MK-0431A-170), and during Weeks 0-54 for participants not on background insulin in the Sitagliptin/Metformin XR and Metformin XR arms (protocol MK-0431A-289), the type of insulin for glycemic rescue was specified to be insulin glargine.

Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: Insulin
Description: Participants who met protocol-specific glycemic rescue criteria received insulin as glycemic rescue therapy; participants on background insulin had their insulin dose increased for glycemic rescue. During Weeks 20-54, for participants who were not on background insulin or rescued with insulin during Weeks 0-20 in the Sitagliptin/Metformin and Metformin arms (protocol MK-0431A-170), and during Weeks 0-54 for participants not on background insulin in the Sitagliptin/Metformin XR and Metformin XR arms (protocol MK-0431A-289), the type of insulin for glycemic rescue was specified to be insulin glargine.

Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: Insulin
Description: Participants who met protocol-specific glycemic rescue criteria received insulin as glycemic rescue therapy; participants on background insulin had their insulin dose increased for glycemic rescue. During Weeks 20-54, for participants who were not on background insulin or rescued with insulin during Weeks 0-20 in the Sitagliptin/Metformin and Metformin arms (protocol MK-0431A-170), and during Weeks 0-54 for participants not on background insulin in the Sitagliptin/Metformin XR and Metformin XR arms (protocol MK-0431A-289), the type of insulin for glycemic rescue was specified to be insulin glargine.