This experimental study is planned to investigate the impact of hypoglycaemia on platelet activation parameters (PAP) during a hyperinsulinaemic hypoglycaemic clamp study. The hypothesis that hypoglycaemia in patients with Diabetes Mellitus, Type 2 (T2DM) leads to increased platelet activation will be tested.

Increased platelet activation is significantly involved in the pathophysiology of micro- and macrovascular diabetic complications. Previously performed studies suggested platelet activation in both, hyper- and hypoglycaemic states, leading to a potentially increased risk for thromboembolic complications. Hypoglycaemia, in particular severe hypoglycaemic episodes, has been associated with increased cardiovascular or overall mortality in previous studies. Potential mechanisms include arrhythmias or increased risk for thromboembolism, based on platelet activation and/or hypercoagulability.

The aim of this experimental study is to investigate the impact of hypoglycaemia on platelet activation parameters (PAP) during a hyperinsulinaemic hypoglycaemic clamp study. We hypothesize that Hypoglycaemia in patients with T2DM leads to increased platelet activation.

The primary objective is to investigate platelet activation during different levels of hypoglycaemia induced by a stepwise hyperinsulinaemic, hypoglycemic clamp experiment in patients with T2DM.

Active study duration will be 5 days for each study participant. 14 subjects with T2DM without history of cardiovascular events or manifest atherosclerosis will be enrolled. During this monocentric, single arm, open, mechanistic trial platelet activation and recovery at one week after the clamp experiment, changes of pro-atherothrombotic markers during the hypoglycaemic clamp as well as counter regulatory hormone response during the clamp will be investigated.

Inclusion Criteria:

• Male or female aged 18-64 years (both inclusive) at the time of signing informed consent
• Subjects diagnosed with type 2 diabetes (diagnosed regarding world health organization [WHO] criteria) and on stable treatment for a period of 90 days prior to screening with metformin as monotherapy or diet only. Stable is defined as unchanged dose
• Body mass index (BMI) between 20.0 and 35.0 kg/m2 (both inclusive)
• HbA1c between 43 and 64 mmol/mol (6.0% - 8.0%) (both inclusive)
• No use of platelet inhibiting therapy (e.g. aspirin, clopidogrel, ticagrelor, prasugrel)

Exclusion Criteria:

• All other forms of diabetes (type 1 diabetes, gestational diabetes) than type 2 diabetes mellitus
• Treatment with any glucose lowering agent(s) other than metformin in a period of 60 days before screening. An exception is short-term treatment (≤ 7 days in total) with insulin due to intercurrent illness
• Impaired hypoglycaemic awareness determined at the discretion of the investigator
• Medical history of arrhythmia as atrial fibrillation, atrial flutter, atrioventricular dissociation disorders or ventricular arrhythmias
• Previously known cardiovascular disease and / or past cardiovascular events, or past episodes of a congestive heart failure syndrome (NYHA II - NYHA IV)
• Severe hypoglycaemic event requiring third party help in the last 6 months
• Known allergy to human insulin or dextrose solution
• Clinically significant abnormal haematology, biochemistry, lipids, hormones, coagulation or urinalysis
• Uncontrolled hypertension defined as resting blood pressure at screening (after resting for 5 min, measured in sitting position) outside the range of 90-160 mmHg for systolic or 50-100 mmHg for diastolic
• Chronic liver failure with severe liver dysfunction as assessed by the investigator
• Alanine Aminotransferase (ALT) or Aspartate Aminotransferase (AST) levels > 3x upper Limit of normal (ULN)
• estimated Glomerular Filtration Rate (eGFR) <45 ml/min/1,73 m2
• Any musculoskeletal disorders holding back from stay in bed in a lying position during the time of the clamp experiments
• Treatment with beta-blockers, antiarrhythmic agents or neuroleptic drugs
• Active smoker or intake of illicit substances
• Regular intake of nonsteroidal anti-inflammatory drugs (NSAIDs)
• Any mental disorders or psychiatric conditions which may interfere with understanding or conduction of study related procedures
• Females of child bearing potential without adequate contraceptive methods (i.e. sterilisation, intrauterine device, vasectomised partner; or medical history of hysterectomy)

Each participant was assessed for Adverse Events from successful Screening until Visit 5 Minimum timeframe for AE assessment: 18 days Maximum timeframe for AE assessment: 42 days

14 subjects could be considered a small patient Group. Given the delayed activation of platelet and coagulation markers in our study, we still can not answer the question, at which glycaemic threshold this activation occurs.