Study of Posaconazole Prophylaxis in Patients Receiving Hematopoietic Stem Cell Allograft (Allo-HSC) at High Risk of Invasive Fungal Infection (IFI)

Inclusion Criteria: * Patient ≥ 18 years of age. There is no maximum age for inclusion * Allo-CSH transplant for hematologic malignancy or benign hemopathy of any type with one or more high risk IFI criteria: * alternative donor (haploidentical intra-family donor, mismatch file donor, placental blood) * sequential conditioning for disease not in remission at the time of transplantation * use of post-transplant cyclophosphamide (PTCY) for GVH prophylaxis * patient who has previously received a HSC allograft * Written informed consent prior to protocol initiation * ECOG \<=2 * Female of childbearing age with negative pregnancy test and on highly effective contraception during treatment and for 12 months after posaconazole discontinuation * Men of childbearing age with effective contraception during treatment and for 6 months after stopping posaconazole. * Hepatitis B, C and HIV serologies negative. * Social security affiliation Exclusion Criteria: * Patients with a history of IFI, whether active or resolved at the time of allografting * Patient with known intolerance to posaconazole * Patients with concomitant treatments FORBIDDING association with posaconazole: ergot alkaloids, CYP3A4 substrates (terfenadine, astemizole, cisapride, pimozide, halofantrine or quinidine), HMG-CoA reductase inhibitors (simvastatin, lovastatin and atorvastatin) or any other contraindicated treatment listed in VIDAL * patients with congenital or acquired QTc prolongation (QTc \>470ms) * Cardiac: systolic ejection fraction \< 50% by transthoracic ultrasound or isotopic method (isotopic gamma-angiography) * Respiratory: DLCOc \<40% of theoretical on EFR * Renal: creatinine clearance \< 50 ml/min (assessed using MDRD method) * Hepatic: transaminases greater than 5 times normal or bilirubin greater than 2 times normal * Pregnant or breast-feeding women, * Women or men of childbearing age without effective contraception * Serious, uncontrolled concomitant infections * Yellow fever vaccination within the last year * Patient protected by law (guardianship, curatorship, safeguard of justice) * Psychological, family, sociological or geographical conditions that may hinder compliance with the study protocol and follow-up schedule * Patient who does not speak or understand French * Participation in any other therapeutic study with an exclusion period still in effect at the time of inclusion or planned participation in another therapeutic study while taking posaconazole