On January 22, 2025, Medexus announced that the FDA had approved GRAFAPEX, an alkylating agent, in combination with fludarabine as a preparative regimen for allogeneic hematopoietic stem cell transplantation (alloHSCT) in adults and pediatric patients aged one year and older with acute myeloid leukemia (AML) or myelodysplastic syndrome (MDS).
GRAFAPEX has received Orphan Drug Designation under the Orphan Drug Act, which grants it up to seven-and-a-half years of regulatory exclusivity for this indication. Medexus holds exclusive commercial rights to GRAFAPEX in the U.S. through a license agreement with medac GmbH, finalized in February 2021.
The efficacy of the newly FDA-approved regimen was assessed in the randomized, active-controlled phase 3 MC-FludT.14/L trial, titled “Treosulfan or busulfan plus fludarabine as conditioning treatment before allogeneic haemopoietic stem cell transplantation for older patients with acute myeloid leukaemia or myelodysplastic syndrome (MC-FludT.14/L): a randomised, non-inferiority”.
A phase 3 open-label, randomized, non-inferiority trial was conducted in 31 transplantation centers across France, Germany, Hungary, Italy, and Poland. The study included patients aged 18-70 with acute myeloid leukemia (AML) or myelodysplastic syndrome (MDS) who were eligible for allogeneic hematopoietic stem cell transplantation (HSCT) but considered at increased risk for standard myeloablative regimens due to age (≥50) or comorbidities. Patients were randomly assigned to receive either 10 g/m² intravenous treosulfan daily for 3 days or 0.8 mg/kg busulfan for 2 days, both with fludarabine.
The primary outcome was event-free survival 2 years after HSCT, with a non-inferiority margin set at a hazard ratio (HR) of 1.3. Efficacy was assessed in all patients who received treatment and completed transplantation, while safety was evaluated in all patients who received the treatment. The trial aimed to compare treosulfan’s efficacy to busulfan as a preparative regimen for HSCT.
Authors: Dietrich Wilhelm Beelen et al.
Ken d’Entremont, Medexus’s Chief Executive Officer, added:
“We are pleased to report this positive development, which marks a strategically important step forward for our business and, importantly, will now benefit eligible patients across the United States. Not only will GRAFAPEX™ make a substantial contribution to alloHSCT in the United States, but it also solidifies Medexus’s leadership position in this therapeutic field.”
About GRAFAPEX
