Open pharmacokinetic study with 5 parallel groups and two treatment phases (bemiparin 3,500 IU multiple dose and bemiparin 115 IU/kg single dose). The bemiparin pharmacokinetic profile will be assessed by measuring its effects on the coagulation cascade. Plasma anti-Xa activity (measured using chromogenic amidolytic assay) in IU per milliliter will be the primary endpoint to assess the pharmacokinetic profile of bemiparin.

Inclusion Criteria:

Non-elderly healthy volunteers (Group I):

• Male or female subjects aged between 18 and 65 years
• body weight, clinical history, physical examination, vital signs (systolic and diastolic blood pressure, heart beat rate and body temperature), ECG and laboratory tests (hemogram and biochemistry) within normal range
• without evidence of significant organic or psychiatric illness
• who have accepted to participate in the study and have signed the written informed consent.

Patients with renal insufficiency (Groups II, III and IV):

• Male or female subjects aged between 18 and 65 years, who will be assigned to one of the following groups according to renal function:

  • Group II: mild renal insufficiency (creatinine clearance > 50 to 80 ml/min);
  • Group III: Moderate renal insufficiency (creatinine clearance: 30 to 50 ml/min);
  • Group IV: Severe renal insufficiency (creatinine clearance < 30 ml/min). The degree of renal insufficiency will be calculated on the basis of determination of creatinine clearance measuring total urinary output over a 24-h period and serum creatinine levels. Urine samples will be collected no more than 2 weeks before the first experimental period.

• Patients with renal insufficiency must have a stable renal function during the 3 months before their inclusion in the study.

• They must have a body weight between 45 and 110 Kg.

• They have to accept to participate in the study and have signed the written informed consent.

Elderly healthy volunteers (Group V):

• Male or female subjects aged > 65 years old who fulfill with the remaining inclusion criteria specified for non-elderly healthy volunteers.

Exclusion Criteria:

Non-elderly healthy volunteers (Group I):

• Previous history of alcoholism or drugs consumption
• Important consumer of exciting drinks
• Hypersensitivity, allergy, idiosyncrasy to medicines
• Taking another medication four weeks before the initiation of the trial including medication without prescription and medicinal plants
• Positive serology of hepatitis B, C or HIV virus
• History or clinic evidence of concomitant disease
• Familiar history of coagulation's disorders
• surgery within the previous 6 months
• Women who are pregnant or who are not using effective contra conceptive methods
• Ethanol, cannabis, cocaine, amphetamine, benzodiazepin or opiate in urine
• Current platelet count < 100.000/mm3 or serum K > 5,5 mEq/L
• Any contraindication to bemiparin administration in order to authorized summary product characteristics
• Healthy volunteers who are not participating in another clinical trial or have not done so in the past 2 months
• To give blood in the four weeks before beginning of the trial

Patients with renal insufficiency or elderly healthy volunteers (Groups II, III, IV, V):

• Previous history of alcoholism or drugs consumption
• Important consumer of exciting drinks
• Hypersensitivity, allergy, idiosyncrasy to medicines
• Treatment with enzymatic inhibitors or inductors medicines
• Administration with ASA of dosis > 125 mg/day and/or NDAIs with half-life > 20 hours or with high antiagregant effect during the previous ten days to the inclusion
• Chronic hepatopatology
• bilirubin levels > 1,5 mg/dl and/or increment of AST/ALT levels twice higher than maximum limit of normality
• prothrombin time 20% higher than maximun limit of normality and haemoglobine < 8gr/dl or albumim levels <3gr/dl
• Previous history of acute infarction of myocardium, cardiac ischemic or arrhythmia
• Acute illness in the previous week to the participation
• Familiar history of coagulation's disorders
• surgery within the previous 6 months
• Women who are pregnant or who are not using effective contra conceptive methods
• Ethanol, cannabis, cocaine, amphetamine, benzodiazepin or opiate in urine
• Current platelet count < 75.000/mm3 or serum K > 6 mEq/L
• Any contraindication to bemiparin administration in order to authorized summary product characteristics
• Healthy volunteers who are not participating in another clinical trial or have not done so in the past 2 months
• To give blood in the four weeks before beginning of the trial
• Subjects in haemodialysis or peritoneal dialysis