Advantage of using Glucophage® SR (a Metofrmin) in non-overweight patients with type-1 Diabetes to improve their glucose control

INTERVENTION: 1. Screening Visit: At the 'screening visit' patients will attend in fasting state (due to C‐peptide levels collection on this visit) and be asked to sign a consent form and data will be collected on age, sex, height, weight, body mass index (BMI), duration of diabetes, total daily insulin dose and incidence of hypoglycemia. Blood samples will be taken for fasting blood glucose, fasting C‐peptide levels, HbA1c, urea and electrolytes (U&E) and liver function tests (LFTs). A complete physical examination and fundoscopy will be done. If available, record of any recent Diabetic retinopathy screening or laser eye treatment will be sought from patient's hospital notes. Patients will be given education on how to do home glucose monitoring (HGM), will be given a HGM booklet and a glucometer. Patients will be advised to do HGM (pre‐breakfast, pre‐lunch, pre‐evening meal and pre‐bed) three days prior to every visit. In addition, patients will be asked check the blood glucose whenever they feel the symptoms of hypoglycemia (defined as capillary blood glucose < 4.0mmol/L with or without symptoms) and record it with date and time. 2. Run‐in period: Patients will receive education about study and an assessment of patient's ability to comply with the protocol will be made. 3. Randomisation: Patients will attend in a non‐fasting state and data will be collected on weight, body mass index (BMI), total daily insulin dose and incidence of hypoglycemia. Blood samples will be taken for HbA1c, U&E and LFTs. Records of hypoglycemia during 'run‐in period' and HGM 3 days prior to randomization visit will be checked. Insulin dosages will be adjusted as required. Patients will be randomized (double blind) to receive: 3.1. Glucophage® SR 5..mg once daily for 1 week, then twice daily for 6 months 3.2. Placebo 4. Intervention period: Patients will attend at week‐1 (day‐7), week‐2 (day‐14) and week‐3 (day‐21). At each of these three visits the record of HGM will be reviewed and insulin CONDITION: Type 1 diabetes ; Nutritional, Metabolic, Endocrine ; Insulin dependent diabetes mellitus PRIMARY OUTCOME: Improvement in glycaemic control as a result of addition of Glucophage® SR compared with placebo. Assessed by measurement of HbA1c at screening, baseline and 1, 2, 3, 4, 5 and 6 months. SECONDARY OUTCOME: 1. Improvement in number of episodes of hypoglycemia in Glucophage® SR arm of study; 2. Reduction in insulin dose in Glucophage® SR arm of the study; All outcomes assessed at screening, baseline and 1, 2, 3, 4, 5 and 6 months. INCLUSION CRITERIA: 1. Male or female, Aged > 18 years In addition, patients should fulfil all the following criteria at the randomisation visit: 2. Type‐1 Diabetic patients with C‐peptide negative result at screening visit (defined as C‐peptide concentration < 0.18nmol/L at a time when blood glucose level is > 5.0mmol/L) 3. Suboptimal glycaemic control (HbA1c 7.5% to 8.5% at screening visit) with or without history of mild hypoglycemia (defined as hypoglycemia not affecting cognitive function and not requiring third party intervention for reversal) 4. History of previous attempts to improve glycaemic control resulting in hypoglycemic episodes (history from hospital medical notes or directly from patients) 5. History of Diabetes for > 1 year 6. BMI 21 to 27 7. Willing and able to comply with the study protocol