Background: The optimal fasting glucose target to achieve an HbA1c <7.0% in patients with T2D remains controversial.

Methods: This open-label RCT conducted in China (ClinicalTrials.gov, NCT02545842), randomly assigned (1:3:3) adults (aged 18-65 years) with uncontrolled T2D (HbA1c >7% to ≤10.5%) on 1-3 OADs to 1 of 3 self-monitored fasting blood glucose (FBG) target groups: ≤5.6 mmol/L (Group 1), ≤6.1 mmol/L (Group 2), or ≤7.0 mmol/L (Group 3). The lowest of 3 consecutive FBG values was used for insulin glargine 100 U/ml titration decisions. Primary endpoint was the proportion of patients achieving an HbA1c <7.0% at 24 weeks.

Results: Of 947 patients randomized (Group 1, n=136; Group 2, n=405; Group 3, n=406), 914 were analyzed (mean age 53.9 years; 56.2% male; mean HbA1c 8.59%), and 885 (93.4%) completed the study. At 24 weeks, 44.4%, 46.1%, and 37.7% of patients achieved an HbA1c <7.0% in Group 1, 2, and 3, respectively (p=0.017; Group 2 vs. Group 3). Significantly more patients in Group 2 than in Group 3 (45.0% vs. 36.5%; p=0.014) achieved an HbA1c <7% without hypoglycemia (BG ≤3.0 mmol/L). Confirmed hypoglycemia (BG ≤3.9 mmol/L) was significantly more frequent in Group 1 vs. Group 3 (38.9 vs. 23.3%, p<0.001) but not in Group 2 vs. Group 3 (27.5% vs. 23.3%; p=0.177). Based on the lowest of 3 consecutive FBG values, the proportions of patients achieving an FBG within their target range at 24 weeks were 70.1%, 67.6% and 79.0% in Groups 1, 2 and 3, respectively. However, based on laboratory fasting plasma glucose (FPG) measurements, these proportions were 31.9%, 39.5% and 47.7%. After re-dividing by actual FPG level at 24 weeks, significantly more patients with an FPG ≤5.6 mmol/L (68.7%, p<0.001) and 5.6< FPG ≤6.1mmol/L (58.2%, p=0.013) achieved an HbA1c <7.0% than those with 6.1< FPG ≤7.0 mmol/L (43.6%).

Conclusions: The optimal FBG target for the majority of patients with T2D appears to be ≤6.1 mmol/L. However, for patients at lower risk of hypoglycemia, an FBG target of ≤5.6 mmol/L may be appropriate.

Disclosure

W. Yang: Speaker's Bureau; Self; AstraZeneca, Bayer AG, Boehringer Ingelheim Pharmaceuticals, Inc., Eli Lilly and Company, Merck & Co., Inc., Merck Sharp & Dohme Corp., Novo Nordisk Inc., Sanofi, Servier. J. Ma: None. G. Yuan: None. L. Li: None. M. Zhang: None. Y. Lu: None. X. Ye: Speaker's Bureau; Self; AstraZeneca, Merck Sharp & Dohme Corp., Novo Nordisk Inc. W. Song: None. M. Liu: None. J. Wu: None. R. Chen: None. N. Cui: Employee; Self; Sanofi. Y. Li: Employee; Self; Sanofi. X. Zhang: None. J. Yang: None.

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