Long Term Efficacy of Rituximab in B-Cell Post Transplantation Lymphoproliferative Disorders (B-PTLD): Update of the Multicenter, Open Label, Phase II Trial (M39037 TRIAL).

Background:

B-PTLD is a rare but severe complication observed after organ transplantation. There is no consensus on treatment modalities in this setting but Rituximab monotherapy has been presented as an effective and well tolerated treatment. Long term efficacy is unknown.

Aim:

We recently published results of the first prospective study on PTLD treatment, using four weekly injection of Rituximab in progressive or non responding tumours after immunosuppression diminution (

Methods:

From may 2000 to December 2001, 43 PTLD after solid organ transplantation have been enrolled in M39037, a franco-belgian multicentric prospective trial. The primary end point was day 80 response rate and one year results were also presented. Participating centres were contacted in order to obtain update data on surviving patients at one year, especially for their tumour status (complete response (CR), partial response (PR) or progressive disease (PD)), date of last information, eventual death and cause of death.

Results:

At one year, on 43 included patients, 26 were still alive, 12 in CR or Cru, one in PR, 10 in PD and two with insufficient information. At this time, update data are available on eight patients, six were in CR or Cru at one year and two in PD. Five patients died by organ failure (n=1), graft rejection (n=1), sudden death (n=2) or heart biopsy complication (n=1); all but one were in CR at this time. Three patients are still alive and in CR. No relapse has been diagnosed and median survival is 1188 days (with a median follow up of 1689 days for surviving patients). Final analysis on all patients will be presented at the ASH meeting.

Conclusion:

Rituximab in monotherapy seems to have a durable efficacy on PTLD after solid organ transplantation with a follow up of more than 4,5 years. Complete results will be presented at the ASH Meeting.