Comparison of Oral Cyclophosphamide vs Doxorubicin in ≥65 Years Old Advanced or Metastatic Soft Tissue Sarcoma Patients

Inclusion criteria: 1. Patient must have signed a written informed consent form prior to any trial specific procedures. When the patient is physically unable to give their written consent, a trust person of their choice, independent from the investigator or the sponsor, can confirm in writing the patient's consent 2. Age ≥65 years (inclusions will be managed to ensure that at least 50% of the randomized patients are ≥75 years old) 3. Diagnosis of soft-tissue sarcoma histologically confirmed by Réseau de Référence en Pathologie des Sarcomes et des Viscères (RRePS) 4. Metastatic or locally advanced disease not amenable to surgery, radiation, or combined modality treatment with curative intent. Palliative radiation therapy is permitted only if direct on nontarget lesion 5. Documentation of disease progression within the last 6 months before randomization 6. Measurable disease, defined as at least 1 unidimensionally measurable lesion on a CT-scan as defined by response evaluation criteria in solid tumors version 1.1 (RECIST v1.1) 7. Life expectancy of at least 6 months 8. Eastern Cooperative Oncology Group (ECOG) performance status ≤2 9. G8 score \>14 10. Left ventricular ejection fraction (LVEF) value by echocardiogram or Multiple gated acquisition scanning (MUGA) ≥55% 11. Adequate bone marrow, renal, and hepatic function, as evidenced by the following within 7 days of study treatment initiation: 1. Absolute neutrophil count (ANC) ≥1,500/mm³ 2. Platelets ≥100,000/mm³ 3. Hemoglobin ≥9.0 g/dL 4. Serum creatinine ≤2 x upper limit of normal (ULN) 5. Glomerular filtration rate (GFR) ≥50 ml/min/1.73m² (calculated with MDRD) 6. Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) ≤2.5 x ULN (≤5.0 × ULN for patients with liver involvement of their cancer ) 7. Total bilirubin ≤1.5 X ULN 8. Alkaline phosphatase ≤2.5 x ULN (≤5 x ULN with liver involvement of their cancer) 9. serum albumin \>25 g/L 10. Prothrombin time (PT)/International normalized ratio (INR) ≤1.5 x ULN Patients who are therapeutically treated with an agent such as warfarin or heparin will be allowed to participate provided that no prior evidence of underlying abnormality in coagulation parameters exists. Close monitoring of at least weekly evaluations will be performed until PT/INR is stable based on a measurement that is pre-dose as defined by the local standard of care 12. Male patients must agree to use adequate contraception for the duration of trial participation and up to 6 months after completing treatment/therapy. Adequate contraception is defined as any medically recommended method (or combination of methods) as per standard of care 13. Patients must be affiliated to a Social Security System (or equivalent) 14. Patient is willing and able to comply with the protocol for the duration of the study including scheduled visits, treatment plan, laboratory tests and other study procedures including follow-up Exclusion Criteria: 1. Previous systemic treatment for advance or metastatic sarcoma 2. Previous neoadjuvant or adjuvant anthracycline treatment for localized sarcoma 3. Soft-tissue sarcoma with the following histological subtypes: dermatofibrosarcoma protuberans, desmoid tumor, alveolar or embryonal rhabdomyosarcoma, Desmoplastic small round cell tumor, Kaposi Sarcoma, Gastro-Intestinal stromal tumor, Peripheral neuroectodermal tumors 4. Primary bone sarcoma (including osteosarcoma, Ewing tumor, chondrosarcoma, and chordoma) 5. Symptomatic or known central nervous system (CNS) metastases 6. Known history of or concomitant malignancy likely to affect life expectancy in the judgment of the investigator and history of radiotherapy mediastinal in the last five years 7. Major surgical procedure, open biopsy, or significant traumatic injury within 28 days before Day 1 of treatment 8. Active cardio vascular disease including any of the following: Congestive heart failure (New York Heart Association (NYHA) ≥Class 2), unstable angina (angina symptoms at rest), new-onset angina (begun within the last 3 months), acute inflammatory cardiopathy, severe arrythmia, high risk of bleeding, cerebrovascular accident within the last 6 months 9. Uncontrolled grade \>2 hypertension. (Systolic blood pressure ≥160 mmHg or diastolic pressure ≥100 mmHg despite optimal medical management) 10. Ongoing infection ≥Grade 2 according to NCI Common Terminology Criteria for Adverse Events version 5.0 (CTCAE v5.0) 11. Known history of human immunodeficiency virus (HIV) infection 12. Known history of chronic hepatitis B or C 13. History of organ allograft 14. Pre-existing acute hemorrhagic cystitis, urinary tract obstruction, acute urinary tract infection 15. Concomitant disease or condition that could interfere with the conduct of the study, or that would, in the opinion of the investigator, pose an unacceptable risk to the subject in this study 16. Substance abuse, medical condition, that may interfere with the patient's participation in the study or evaluation of the study results 17. Known hypersensitivity to any of the study drugs, study drug classes, or excipients in the formulation 18. Inability to swallow oral medications, any malabsorption condition. 19. Persons deprived of their liberty or under protective custody or guardianship 20. Participation in another therapeutic trial within the 30 days prior to randomization and during the study 21. Patients having received live attenuated vaccine therapy used for prevention of diseases as influenza, chickenpox, zoster, measles, mumps, rubella, tuberculosis, rotavirus or yellow fever within 4 weeks of the first dose of study drug. These vaccinations are not permitted during the study up to 6 months after the last treatment 22. Patients unwilling or unable to comply with the medical follow-up required by the trial because of geographic, familial, social, or psychological reasons