Objectives: To compare characteristics of patients with type 2 diabetes mellitus (T2DM) who did/did not achieve short-term (3-12 months) and/or long-term (24-36 months) glycemic control (HbA1c < 7%) following treatment with metformin (MET) monotherapy and determine factors associated with glycemic control. Methods: This was a retrospective study using administrative claims from a national health plan. Patients with T2DM on MET monotherapy for ≥1 year, HbA1c ≥7% and initiating a new glucose lowering medication between January 2010-December 2014 were eligible for this study with date of the first prescription set as index date. Patients were required to have ≥1 HbA1c between 24-36 months post-index; a subset of patients with HbA1c values between 3-12 months was identified. Descriptive analyses were used to compare patients by achievement of glycemic control. Multivariable analyses were used to evaluate factors associated with glycemic control. Results: A total of 7,416 patients were eligible of which 6,561 had data for short-term assessment. Mean A1c (%) during pre-index was 8.2+/-1.3 which decreased to 7.3+/- 1.1 in the short-term and 7.5+/-1.3 in long term, with 39.8% achieving long-term glycemic control. Among patients achieving glycemic control in the short-term (44.4%), 58.2% maintained glycemic control in long-term. For every 1.0% higher HbA1c at baseline, odds of attaining glycemic control decreased by 16% in the short-term and 12% in the long-term. Treatments associated with greater odds ratio (OR) (95% CI) of achieving HbA1c <7% in long-term were SGLT2 inhibitors [OR= 2.45 (1.93-3.12)], GLP-1 RA [OR= 1.95 (1.60-2.36)] and Thiazolidinediones [OR= 1.73 (1.52-1.96)]. Conclusion: Although the majority of patients intensifying treatment after MET monotherapy did not achieve optimal glycemic goals in the long term, understanding how to facilitate treatments that encourage better glycemic control can aid in treatment selection. Disclosure S.K. Bajpai: Employee; Self; Eli Lilly and Company. R. Nair: Stock/Shareholder; Self; Abbott Laboratories, AbbVie Inc., GlaxoSmithKline plc. T. Changamire: Employee; Self; Humana. R. Sheer: None. Q. Wang: None. H. Patel: Employee; Self; Eli Lilly and Company. Stock/Shareholder; Self; Eli Lilly and Company.