Table 1.
Baseline patient and clinical characteristics of the included studies
| Study | Design | N | Mean age, years | Sex, % men | BMI, kg/m2 | Baseline HbA1c, % | T2DM duration, years | Add‐on therapy | Extension study | DPP‐4 inhibitor dose | SU dose | Intermediate time point, weeks | Final time point, weeks | Drop out, %, and handling strategy |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Foley 2009 | R, DB | 811 | 54.8 | 55.8 | 30.7 | 8.7 | 2.2 | N | N | Vildagliptin, 50 mg twice daily | Gliclazide, 80‐320 mg once daily | 24, 52 | 104 | 25.7%, LOCF |
| Ahren 2010 | R, DB | 258 | 57.5 | 53.6 | 31.8 | 7.3 | 5.7 | Y, Metformin | Y | Vildagliptin, 50 mg twice daily | Glimepiride, 2‐6 mg once daily | 24, 52 | 104 | NR |
| Matthews 2010 | R, DB | 1357 | 57.5 | 53.5 | 31.6 | 7.2 | 5.7 | Y, Metformin | N | Vildagliptin, 50 mg twice daily | Glimepiride, 2‐6 mg once daily | 24, 53 | 104 | 37.6%, LOCF |
| Seck 2010 | R, DB | 504 | 57.3 | 60.1 | 31.1 | 7.3 | 5.8 | Y, Metformin | N | Sitagliptin, 100 mg once daily | Glipizide, 5‐20 mg once daily | 24, 54 | 104 | 56%, OC |
| Gallwitz 2012 | R, DB | 504 | 59.8 | 60.5 | 30.3 | 7.7 | NR | Y, Metformin | N | Linagliptin, 5 mg once daily | Glimepiride, 1‐4 mg once daily | 28, 52 | 104 | 23%, LOCF |
| Goke 2013 | R, DB | 312 | 57.5 | 52.4 | 31.4 | 7.7 | 5.5 | Y, Metformin | Y | Saxagliptin, 5 mg once daily | Glipizide, 5‐20 mg once daily | 24, 52 | 104 | 73%, LOCF |
| Ahren 2014 | R, DB | 602 | 55.1 | 50.1 | NR | 8.2 | 6.2 | Y, Metformin | N | Sitagliptin, 100 mg once daily | Glimepiride, 2‐4 mg once daily | 24, 52 | 104 | 33%, LOCF |
| Del 2014, 12.5 mg | R, DB | 1317 | 55.4 | 48.9 | 31.2 | 7.6 | 5.6 | Y, Metformin | N | Alogliptin, 12.5 mg once daily | Glipizide, 5‐20 mg once daily | 26, 52 | 104 | 22%, LOCF |
| Del 2014, 25 mg | R, DB | 1322 | 55.4 | 50.8 | 31.2 | 7.6 | 5.5 | Y, Metformin | N | Alogliptin, 25 mg once daily | Glipizide, 5‐20 mg once daily | 26, 52 | 104 | 22%, LOCF |
Abbreviations: BMI, body mass index; DB, double‐blind; LOCF, last observation carried forward; N, no; NR, not reported; OC, observed cases; R, randomized; Y, yes.