Phase I/II trial of PIXY321 to enhance engraftment following autologous bone marrow transplantation for lymphoid malignancy.

PURPOSE

A phase I/II study of PIXY321 following high-dose therapy (HDT) and autologous bone marrow transplantation (ABMT) was conducted to evaluate the safety and clinical potential of this agent.

PATIENTS AND METHODS

Fifty patients with Hodgkin's disease or non-Hodgkin's lymphoma (NHL) undergoing HDT and ABMT received PIXY321 post-ABMT in doses that ranged from 50 to 1,000 micrograms/m2/d either as intravenous (i.v.) or subcutaneous (SC) dosing until engraftment was reached.

RESULTS

If all doses are considered together, the median time to reach an absolute neutrophil count (ANC) > or = 500/microL was 18 days and the median time to platelet transfusion independence was 21 days. At the estimated optimum dose of 750 micrograms/m2/d by SC injection once daily, the median time to reach an ANC > or = 500/microL was 15 days and the median time to platelet transfusion independence was 16 days. Historical control patients who received granulocyte-macrophage colony-stimulating factor (GM-CSF) had a median time to an ANC > or = 500/microL of 19 days and a median time to platelet independence of 26 days.

CONCLUSION

The administration of PIXY321 post-ABMT was generally well tolerated and resulted in prompt engraftment in the majority of patients who underwent HDT and ABMT for lymphoid malignancies. The optimum dose and route of administration of PIXY321 suggested by this trial was 750 micrograms/m2/d by once-daily SC injection. Compared with historical control patients who received 2-hour i.v. GM-CSF, patients who received PIXY321 at 750 micrograms/m2/d by SC injection once daily had an improvement in the median days to neutrophil and platelet engraftment by 4 and 10 days, respectively.