Phase I-II trial of pentoxifylline for the prevention of transplant-related toxicities following bone marrow transplantation.

Disease relapse and transplant related toxicities have limited the application of bone marrow transplantation (BMT) in the treatment for hematologic malignancies. Because elevated levels of tumor necrosis factor alpha (TNF-alpha) have been correlated with the development of transplant related complications, we conducted a phase I-II trial of pentoxifylline (PTX), a xanthine derivative capable of down-regulating TNF-alpha production, in patients with hematologic malignancies undergoing BMT. Thirty consecutive adult patients (median age, 34) were entered and received either an allogeneic (n = 26) or autologous (n = 4) BMT. Patients were enrolled at increasing dose levels (1,200, 1,600, and 2,000 mg/d) from day -10 through day +100 posttransplant. PTX was well tolerated with no significant adverse side effects noted at any of the dose levels administered. The actuarial day 100 survival for these 30 patients was 90% (95% confidence interval 79% to 100%). When compared with a good risk control group, PTX recipients experienced less mucositis (3.7 +/- 1.1 v 18.7 +/- 1.1 days, P = .004), less hepatic venocclusive disease (10% v 65%, P = .001), a lower incidence of renal insufficiency (3% v 65%, P = .0003), required less days of total parenteral nutrition (TPN) (24.0 +/- 1.3 v 35.0 +/- 2.4, P = .001) and were discharged from the hospital earlier than controls (day 26.0 +/- 1.8 v 37.0 +/- 3.8, P = .01). In addition the incidence of graft-versus-host disease (GVHD) greater than or equal to grade II was also reduced among the PTX recipients (35% v 68%, P = .03). PTX at doses in excess of 1,200 mg/d further reduced the severity of mucositis, and TPN requirements resulting in earlier hospital discharge than patients receiving 1,200 mg/d of PTX. In this study oral administration of PTX in doses up to 2,000 mg/d was well tolerated and associated with a reduction in morbidity and mortality in patients undergoing BMT. Prospective randomized trials are currently in progress to test these preliminary observations.