Table 1.

Characteristics and primary findings of the SWITCH 1 and SWITCH 2 trials

	SWITCH 1a (NCT02034513)	SWITCH 2b (NCT02030600)
Design	Multicentre (84 sites in US and 6 in Poland), randomised, double-blinded, two-period (32 weeks each) crossover	Multicentre (152 sites in US), randomised, double-blinded, two-period (32 weeks each) crossover
Participants	Type 1 diabetes mellitus; n = 501 adults	Type 2 diabetes mellitus; n = 721 adults
Eligibility	≥1 hypoglycaemia risk factors and previously treated with either a basal–bolus regimen or continuous subcutaneous insulin infusion for ≥ 26 weeks	≥1 hypoglycaemia risk factors and previously treated with basal insulin with or without oral antidiabetic drugs for ≥ 26 weeks. Participants treated with bolus/premixed insulin or sulfonylurea/meglitinide within 26 weeks of the first trial visit were excluded
Treatment	Basal–bolus therapy Degludec or glargine U100 once daily, administered either in the morning or in the evening as determined by randomisation. Insulin aspart was the mealtime insulin	Basal-only therapy IDeg or glargine U100 once daily, administered either in the morning or in the evening as determined by randomisation. Pre-trial OAD(s) were continued
Duration	2 × 32 weeks (titration: weeks 1–16 and 32–48; maintenance: weeks 17–32 and 49–64)	2 × 32 weeks (titration: weeks 1–16 and 32–48; maintenance: weeks 17–32 and 49–64)
Efficacy findings	Non-inferiority of degludec vs. glargine U100 with respect to HbA1c was confirmed for the titration period and the maintenance period (6.9 vs. 6.8% [52 mmol/mol vs. 51 mmol/mol] and 7.0 vs. 7.0% [52 mmol/mol vs. 53 mmol/mol], for weeks 32 and 64, respectively)	Non-inferiority of IDeg vs. glargine U100 with respect to HbA1c was confirmed for the titration period and the maintenance period (7.1 vs. 7.0% [54 mmol/mol vs. 53 mmol/mol] and 7.1 vs. 7.1% [54 mmol/mol vs. 54 mmol/mol], for weeks 32 and 64, respectively)
Safety findings	The cumulative rates of severe hypoglycaemia for the three different hypoglycaemia endpointsc were significantly lower, by 6–36%, depending on the endpoint and time period, for degludec vs. glargine U100 during both the maintenance period and the full treatment period	The cumulative rate of severe hypoglycaemia was numerically lower, by 23–51%, for degludec vs. glargine U100, and these differences were statistically significant for all but one of the endpoints

Secondary confirmatory endpoints: number of severe or BG-confirmed symptomatic nocturnal (00:01–05:59) hypoglycaemic episodes and proportion of participants with severe hypoglycaemia during the maintenance period

Glargine U100, insulin glargine 100 units/mL

^aLane et al. [2]

^bWysham et al. [3]

^cPrimary endpoint: number of severe (requiring third-party aid, externally adjudicated) or blood glucose (BG)-confirmed (< 56 mg/dL) symptomatic hypoglycaemic episodes during the maintenance period