This randomized, placebo-controlled phase IIb study (PHOEBUS trial) aims to evaluate the activity of fecal microbiotherapy MaaT033 to improve survival through the prevention of transplant-related complications in eligible alloHCT patients
Age ≥ 50 years old
Presence of a hematologic malignancy for which an alloHCT is indicated with a reduced toxicity or reduced intensity conditioning regimen
Patients with polynuclear neutrophils > 0.5 G/L
Patients having received wide spectrum antibiotics within the last 90 days prior to inclusion
Patients planned to receive a non-myeloablative conditioning regimen (2 Gray total body irradiation (TBI) +/- purine analog, fludarabine + cyclophosphamide or equivalent)
Patients planned to receive a conventional myeloablative conditioning regimen (e.g. high dose cyclophosphamide and high dose TBI (≥10Gy); high dose busulfan (12.8 mg/kg IV) + high dose cyclophosphamide)
Patients receiving a manipulated graft (in-vitro T-cell depletion)
Patients planned to receive a conditioning regimen with alemtuzumab