The CLEAR study: a 5-day, 3-g loading dose of mycophenolate mofetil versus standard 2-g dosing in renal transplantation

BACKGROUND AND OBJECTIVES

Adequate early mycophenolic acid (MPA) exposure is associated with lower rates of acute rejection in renal transplantation. The aim of this randomized controlled trial was to determine if higher initial mycophenolate mofetil (MMF) doses increased the proportion of patients reaching therapeutic MPA levels (30 to 60 mg.h/L) by day 5.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

De novo renal transplant patients were randomized to receive intensified dosing of MMF (1.5 g twice daily on days 1 to 5, then 1.0 g twice daily) or standard dosing (1.0 g twice daily). All recipients received tacrolimus and prednisone. Full MPA areas under the curve (AUCs) were completed on days 3 and 5, whereas a limited sampling strategy was utilized at four subsequent time points.

RESULTS

At day 5, 47.5% of the MMF 3-g arm achieved the MPA therapeutic window versus 54.4% of the MMF 2-g arm. However, MPA AUC levels were significantly higher in the 3-g arm at day 3 and 5. This resulted in a trend for fewer treated acute rejections at 6 months. Significantly more acute rejections (treated, biopsy-proven including and excluding borderline) occurred in patients with MPA AUC levels<30 mg.h/L compared with those >or=30 mg.h/L at day 5. No significant differences were seen in common adverse events.

CONCLUSIONS

A limited intensified dose of MMF increased early MPA exposure and was well tolerated. Further studies are required to determine whether limited intensified MMF dosing can reduce acute rejection.

Two different schedules for integrating filgrastim as adjuvant therapy in the treatment of patients with advanced stage Hodgkin's lymphoma receiving MOPP/ABV hybrid chemotherapy

PURPOSE

Management of advanced-stage Hodgkin's disease with a MOPP/ABV hybrid regimen (mechlorethamine, vincristine, procarbazine, prednisone, Adriamycin, bleomycin and vinblastine) has yielded a high complete response rate (75-85%). However, myelosuppression can limit delivery of treatment. Filgrastim has been shown to reduce chemotherapy-related neutropenia and allow for on-time administration of planned doses of chemotherapeutic agents. The objective of this study was to find the best way to integrate filgrastim with the MOPP/ABV hybrid regimen.

METHODS

Enrolled in this study were 24 patients (aged 18-52 years) with newly diagnosed, histologically documented Hodgkin's disease. In schedule I, patients received filgrastim (5 microg/kg s.c. daily) beginning on day 9, 24 h after administration of ABV. In schedule II, patients received filgrastim concomitantly with procarbazine on days 2-7 (starting 24 h after day-1 MOPP administration and stopping 24 h before ABV administration) as well as after ABV beginning on day 9. Filgrastim after ABV administration was administered until two consecutive ANC readings of 10 x 10(9)/l were achieved.

RESULTS

All patients were able to complete all six cycles of therapy. There was a trend to fewer dose reductions in schedule II (0.76%) as compared to schedule I (4.2%) with a P-value of 0.077 (chi-squared test). Specifically, 11.6% of MOPP courses and 5.5% of ABV courses were dose-reduced in schedule I versus 1.7% and 1.4%, respectively, in schedule II.

CONCLUSION

In conclusion, filgrastim was effective in supporting the delivery of the MOPP/ABV chemotherapy. Concomitant administration of filgrastim with procarbazine (days 2-7) appears to be safe and allows the maximum dose intensity of this therapy.

Coronary sinus sampling of cytokines after heart transplantation: evidence for macrophage activation and interleukin-4 production within the graft

OBJECTIVES

This study was undertaken to evaluate the organ-specific release of cytokines after heart transplantation and to assess any correlation with transplant rejection. This cytokine profile should document the relative activation of mononuclear cell subsets within the graft.

BACKGROUND

Up to 60% of mononuclear cells infiltrating the cardiac allograft during rejection are macrophages, but their role is undetermined. The T lymphocytes are activated, but the activity of specific T cell subsets is not known. We sought to assess for the first time in humans the in vivo activation of mononuclear cell subsets by measuring coronary sinus cytokine levels after heart transplantation.

METHODS

Paired superior vena cava and coronary sinus serum samples were assayed for interleukin (IL)-2, IL-4 and IL-6, soluble IL-2 receptors, tumor necrosis factor-alpha and neopterin in 10 patients at the time of 40 routine endomyocardial biopsy procedures. All cytokine measurements were made by using enzyme-linked immunosorbent assay; neopterin was measured by using radioimmunoassay.

RESULTS

Interleukin-2 levels were not detectable (< 0.8 U/ml) in either the superior vena cava or the coronary sinus in the presence or absence of rejection. Interleukin-2 receptor levels were uniformly elevated to 1,283 U/ml in the superior vena cava and to 1,232 U/ml in the coronary sinus, with no correlation with rejection severity. Interleukin-4 levels were consistently higher in coronary sinus serum than in peripheral blood (229 vs. 61 pg/ml, p < 0.0005), but there was no relation with rejection. Interleukin-6 levels were higher in the coronary sinus than in the superior vena cava (200 vs. 120 pg/ml, p < 0.05). Tumor necrosis factor-alpha showed consistently elevated levels in coronary sinus serum (68 vs. 17 pg/ml, p < 0.0005), with no relation with rejection. Neopterin, which is produced only by activated macrophages, was also consistently elevated in the coronary sinus (2.5 vs. 2.2 nmol, p = 0.08).

CONCLUSIONS

The cardiac allograft is a major source of cytokines after heart transplantation. The cytokine profile allows the activity of subsets of the mononuclear cell infiltrate to be investigated. Elevated coronary sinus activity of the macrophage-specific metabolite neopterin suggests macrophage activation within the allograft. This possibility is supported by elevated coronary sinus levels of tumor necrosis factor-alpha and IL-6. The T lymphocytes are activated, as evidenced by high soluble IL-2 receptor levels, but IL-2 production was suppressed by conventional immunosuppressive therapy. Coronary sinus IL-4 levels represent T helper-2 cell activation within the graft despite immunosuppression. We could find no temporal relation between the coronary sinus or superior vena cava cytokine concentration or profile and severity of rejection on concurrent biopsy studies.