| E.1 Medical condition or disease under investigation | 
| E.1.1 | Medical condition(s) being investigated |  | 
| E.1.1.1 | Medical condition in easily understood language |  | 
| E.1.1.2 | Therapeutic area | Diseases [C] - Cardiovascular Diseases [C14] | 
| MedDRA Classification | 
| E.1.2 Medical condition or disease under investigation | 
| 
| E.1.2 | Version | 20.0 |  
| E.1.2 | Level | PT |  
| E.1.2 | Classification code | 10075049 |  
| E.1.2 | Term | Peripheral venous disease |  
| E.1.2 | System Organ Class | 10047065 - Vascular disorders |  | 
| E.1.3 | Condition being studied is a rare disease | No | 
| E.2 Objective of the trial | 
| E.2.1 | Main objective of the trial | 
| To measure the extent of the effect of oral Sulodexide compared with placebo in reducing the intensity of leg symptoms associated with chronic venous disease. |  | 
| E.2.2 | Secondary objectives of the trial | 
| The secondary efficacy endpoints of the study will include: • A measure of patient-related outcome using the Visual Analogical Scale (VAS) for the overall health state, to be recorded at Baseline and at the Final Visit;
 • A measure of quality of life, using the questionnaire CIVIQ-14, to be recorded at Baseline and at the Final Visit.
 The Safety endpoints will include:
 • Recording of all adverse events according to the standard procedures;
 • Recording of vital signs (systolic and diastolic blood pressure and heart rate seated at rest) at Baseline, Intermediate Visit and Final Visit.
 
 |  | 
| E.2.3 | Trial contains a sub-study | No | 
| E.3 | Principal inclusion criteria | 
| 1. Male and female patients of age ≥ 18 years; 2. Able and willing to issue a signed informed consent after appropriate information and to provide a written authorization for disclosure of protected health information;
 3. With chronic venous disease;
 4. Classified by the attending physician in CEAP clinical classes 2 to 4;
 5.With symptomatic disease (where "symptomatic" disease in this study means: at least 2 symptoms among those composing the primary outcome measure and for a total of at least 6 score points);
 6.Female participants must be:
 •of non-childbearing potential, i.e.: post-menopausal (at least 2 years without spontaneous menses) or surgically sterile (bilateral tubal occlusion or hysterectomy) or ablation of both ovaries;
 or
 •of childbearing potential with a negative pregnancy test result at Visit 1 AND agreeing to use a highly effective method of contraception (i.e. with failure rate of less than 1% per year).
 
 |  | 
| E.4 | Principal exclusion criteria | 
| 1. Patients considered, by the attending physician, unable to comply with the study procedures; 2. Women who are pregnant or during puerperium (first 6 weeks after birth) or breastfeeding at the time of examination for inclusion in the study;
 3. Sexually active women, unless willing to apply an effective method of contraception during the study;
 4. Patients with a BMI ≥ 35 at screening;
 5. Patients with active cancer or cancer in remission from less than 5 years;
 6. Patients with lymphoedema;
 7. Patients with chronic heart failure with swelling requiring diuretic treatment;
 8. Patients under any type of anticoagulant treatment;
 9. Patients receiving double anti-platelet therapy;
 10. Patients under treatment with drugs that may produce oedema (e.g., calcium antagonists);
 11. Patients under treatment with systemic and/or topical phlebotropic/vasotonic drugs or substances in the last 30 days prior to randomisation;
 12. Patients using compression stockings or bandages;
 13. Patients having had invasive treatment of the superficial or deep venous compartment of the lower legs (e.g., surgery, sclerotherapy, minimal invasive treatment for varicose veins);
 14. Patients participating in other clinical trials during the last 30 days prior to screening;
 15. Patients with known hypersensitivity or intolerance to study medications or their formulation excipients.
 
 |  | 
| E.5 End points | 
| E.5.1 | Primary end point(s) | 
| The primary study endpoint is the change from baseline in leg symptoms intensity at the end of treatment. The primary measure is therefore the symptom intensity scoring, which will record – separately in the right and left leg - the intensity of the most common among the symptoms listed in the SYM Vein Consensus statement:  pain/aching, heaviness, feeling of swelling, cramps, itching and fatigue.
 Each symptom in both legs will be scored with a 7-step scale: 0=absent; 1=barely perceptible, 2=mild, 3=moderate, 4=important, 5=severe, 6=unbearable. The total composite score, which may range 0 to 72, will be calculated and will represent the primary measure of the primary study endpoint.
 
 |  | 
| E.5.1.1 | Timepoint(s) of evaluation of this end point |  | 
| E.5.2 | Secondary end point(s) | 
| The secondary efficacy endpoints of the study will include: • A measure of patient-related outcome using the Visual Analogical Scale (VAS) for the overall health state, to be recorded at Baseline and at the Final Visit;
 • A measure of quality of life, using the questionnaire CIVIQ-14, to be recorded at Baseline and at the Final Visit.
 The Safety endpoints will include:
 • Recording of all adverse events according to the standard procedures;
 • Recording of vital signs (systolic and diastolic blood pressure and heart rate seated at rest) at Baseline, Intermediate Visit and Final Visit.
 
 |  | 
| E.5.2.1 | Timepoint(s) of evaluation of this end point | 
| Secondary efficacy endpoints will be evaluated 60 days from baseline Secondary efficacy endpoints will be evaluated throughout the study
 |  | 
| E.6 and E.7 Scope of the trial | 
| E.6 | Scope of the trial | 
| E.6.1 | Diagnosis | No | 
| E.6.2 | Prophylaxis | No | 
| E.6.3 | Therapy | No | 
| E.6.4 | Safety | Yes | 
| E.6.5 | Efficacy | Yes | 
| E.6.6 | Pharmacokinetic | No | 
| E.6.7 | Pharmacodynamic | No | 
| E.6.8 | Bioequivalence | No | 
| E.6.9 | Dose response | No | 
| E.6.10 | Pharmacogenetic | No | 
| E.6.11 | Pharmacogenomic | No | 
| E.6.12 | Pharmacoeconomic | No | 
| E.6.13 | Others | No | 
| E.7 | Trial type and phase | 
| E.7.1 | Human pharmacology (Phase I) | No | 
| E.7.1.1 | First administration to humans | No | 
| E.7.1.2 | Bioequivalence study | No | 
| E.7.1.3 | Other | No | 
| E.7.1.3.1 | Other trial type description |  | 
| E.7.2 | Therapeutic exploratory (Phase II) | No | 
| E.7.3 | Therapeutic confirmatory (Phase III) | No | 
| E.7.4 | Therapeutic use (Phase IV) | Yes | 
| E.8 Design of the trial | 
| E.8.1 | Controlled | Yes | 
| E.8.1.1 | Randomised | Yes | 
| E.8.1.2 | Open | No | 
| E.8.1.3 | Single blind | No | 
| E.8.1.4 | Double blind | Yes | 
| E.8.1.5 | Parallel group | Yes | 
| E.8.1.6 | Cross over | No | 
| E.8.1.7 | Other | No | 
| E.8.2 | Comparator of controlled trial | 
| E.8.2.1 | Other medicinal product(s) | No | 
| E.8.2.2 | Placebo | Yes | 
| E.8.2.3 | Other | No | 
| E.8.2.4 | Number of treatment arms in the trial | 2 | 
| E.8.3 | The trial involves single site in the Member State concerned | No | 
| E.8.4 | The trial involves multiple sites in the Member State concerned | Yes | 
| E.8.4.1 | Number of sites anticipated in Member State concerned | 8 | 
| E.8.5 | The trial involves multiple Member States | Yes | 
| E.8.5.1 | Number of sites anticipated in the EEA | 24 | 
| E.8.6 Trial involving sites outside the EEA | 
| E.8.6.1 | Trial being conducted both within and outside the EEA | Yes | 
| E.8.6.2 | Trial being conducted completely outside of the EEA | No | 
| E.8.6.3 | If E.8.6.1 or E.8.6.2 are Yes, specify the regions in which trial sites are planned | 
| Russian Federation |  
| Czechia |  
| Italy |  
| Poland |  
| Portugal |  
| Slovakia |  | 
| E.8.7 | Trial has a data monitoring committee | No | 
| E.8.8 | Definition of the end of the trial and justification where it is not the last
                        visit of the last subject undergoing the trial | 
| Last visit of the last subject |  | 
| E.8.9 Initial estimate of the duration of the trial | 
| E.8.9.1 | In the Member State concerned years | 1 | 
| E.8.9.1 | In the Member State concerned months | 8 | 
| E.8.9.1 | In the Member State concerned days |  | 
| E.8.9.2 | In all countries concerned by the trial years | 1 | 
| E.8.9.2 | In all countries concerned by the trial months | 8 |