Table 4.

Summary of results for the direct comparison of all DPP-4 inhibitors versus comparator (binominal outcome measures)

Endpoint	Alogliptin 25 mg QD		Linagliptin 5 mg QD		Saxagliptin 5 mg QD		Sitagliptin 100 mg/day		Vildagliptin 50 mg BID
	Odds ratio (95% CI)	I 2 (%)	Odds ratio (95% CI)	I 2 (%)	Odds ratio (95% CI)	I 2 (%)	Odds ratio (95% CI)	I 2 (%)	Odds ratio (95% CI)	I 2 (%)
Patients achieving HbA1c <7	3.157* [66, 84] (1.87–5.49)	0.0	2.772* [93, 98] (1.74–4.41)	0.0	1.909* [107] (1.03–3.56)	–a	3.934* [110, 112, 118] (2.20–7.05)	63.7b	4.105* [75] (1.95–8.63)	–a
Patients with hypoglycemic event	0.949 [66, 84] (0.06–15.45)	–a	0.311 [93, 97, 98] (0.04–2.55)	0.0	0.257 [106, 107] (0.49–13.13)	–a	0.924 [80, 87, 110, 112, 114, 118] (0.23–3.77)	0.0	–	–

Endpoint	Alogliptin 25 mg QD + metformin		Linagliptin 5 mg QD + metformin		Saxagliptin 5 mg QD + metformin		Sitagliptin 100 mg/day + metformin		Vildagliptin 50 mg BID + metformin
	Odds ratio (95% CI)	I 2 (%)	Odds ratio (95% CI)	I 2 (%)	Odds ratio (95% CI)	I 2 (%)	Odds ratio (95% CI)	I 2 (%)	Odds ratio (95% CI)	I 2 (%)
Patients achieving HbA1c <7	7.005* [51, 74] (1.41–34.70)	76.5b	4.125* [94, 102] (1.80–9.45)	14.8	2.272* [56, 89, 104, 108] (1.69–3.06)	53.7b	2.869* [90, 111, 112, 119, 120] (1.67–4.92)	80.0b	2.302* [58, 126] (1.75–3.03)	0.0
Patients with hypoglycemic event	0.069 [74] (0.004–1.34)	–a	1.394 [94, 101] (0.17–11.62)	–a	0.950 [56, 89, 108] (0.54–1.66)	0.0	0.910 [111, 119, 120] (0.48–1.74)	0.0	1.911 [60, 88, 126] (0.33–11.09)	0.0

Endpoint	Alogliptin 25 mg QD + SU		Linagliptin 5 mg QD + SU		Saxagliptin 5 mg QD + SU		Sitagliptin 100 mg/day + SU		Vildagliptin 50 mg BID + SU
	Odds ratio (95% CI)	I 2 (%)	Odds ratio (95% CI)	I 2 (%)	Odds ratio (95% CI)	I 2 (%)	Odds ratio (95% CI)	I 2 (%)	Odds ratio (95% CI)	I 2 (%)
Patients achieving HbA1c <7	2.407* [92] (1.34–4.34)	–a	4.716* [99] (1.38–16.17)	–a	3.021* [103] (1.81–5.04)	–a	1.263 [115] (0.50–3.19)	–a	5.536 [62, 72] (0.89–34.36)	92.6b
Patients with hypoglycemic event	0.849 [92] (0.39–1.86)	–a	1.184 [99] (0.35–3.97)	–a	1.523 [103] (0.90–2.58)	–a	3.438* [34, 115] (1.00–11.78)	0.0	3.848 [62, 72] (0.78–19.00)	0.0

Endpoint	Alogliptin 25 mg QD + metformin + SU		Linagliptin 5 mg QD + metformin + SU		Saxagliptin 5 mg QD + metformin + SU		Sitagliptin 100 mg/day + metformin + SU		Vildagliptin 50 mg BID + metformin + SU
	Odds ratio (95% CI)	I 2 (%)	Odds ratio (95% CI)	I 2 (%)	Odds ratio (95% CI)	I 2 (%)	Odds ratio (95% CI)	I 2 (%)	Odds ratio (95% CI)	I 2 (%)
Patients achieving HbA1c <7	–	–	–	–	–	–	–	–	–	–
Patients with hypoglycemic event	–	–	1.689* [100] (1.16–2.47)	–a	–	–	8.699* [115] (1.07–70.76)	–a	2.791 [124] (0.73–10.72)	–a

Endpoint	Alogliptin 25 mg QD + pioglitazone		Linagliptin 5 mg QD + pioglitazone		Saxagliptin 5 mg QD + pioglitazone		Sitagliptin 100 mg/day + pioglitazone		Vildagliptin 50 mg BID + pioglitazone
	Odds ratio (95% CI)	I 2 (%)	Odds ratio (95% CI)	I 2 (%)	Odds ratio (95% CI)	I 2 (%)	Odds ratio (95% CI)	I 2 (%)	Odds ratio (95% CI)	I 2 (%)
Patients achieving HbA1c <7	2.874* [77, 91] (1.67–4.95)	54.6b	1.71* [96] (1.09–2.69)	–a	–	–	3.95* [57] (2.71–5.76)	–a	2.82* [71, 76] (1.96–4.07)	0.0
Patients with hypoglycemic event	7.32 [91] (0.38–143.28)	–a	3.561 [96] (0.18–69.47)	–a	–	–	1.494 [57] (0.25–9.02)	–a	0.778 [71, 76] (0.09–6.91)	24.0

Endpoint	Alogliptin 25 mg QD + insulin		Linagliptin 5 mg QD + insulin		Saxagliptin 5 mg QD + insulin		Sitagliptin 100 mg/day + insulin		Vildagliptin 50 mg BID + insulin
	Odds ratio (95% CI)	I 2 (%)	Odds ratio (95% CI)	I 2 (%)	Odds ratio (95% CI)	I 2 (%)	Odds ratio (95% CI)	I 2 (%)	Odds ratio (95% CI)	I 2 (%)
Patients achieving HbA1c <7	–	–	–	–	–	–	–	–	–	–
Patients with hypoglycemic event	–	–	–	–	–	–	0.934 [40, 61] (0.23–3.80)	78.7b	1.639 [70] (0.97–2.76)	–a

BID twice daily, CI confidence interval, HbA _1c glycosylated hemoglobin, QD once daily, SU sulfonylurea

* Statistically significant versus comparator

^aOnly one study eligible

^b I ² may represent moderate heterogeneity