FTY720 and everolimus in de novo renal transplant patients at risk for delayed graft function: results of an exploratory one-yr multicenter study.

This exploratory, multicenter, open-label study evaluated the efficacy and safety of FTY720, as a part of an immunosuppressive regimen, in combination with everolimus and steroids in de novo renal transplant recipients at increased risk of delayed graft function (DGF). Patients received FTY720 (5 mg) and everolimus (4 mg) 2-12 h pre-transplantation, followed by 2.5 mg/d FTY720 and concentration-controlled everolimus (4-8 ng/mL) post-transplant for 12 months. Induction therapy was prohibited. After enrollment of 56 of the planned 200 patients between 2000 and 2002, the recruitment was terminated. The primary endpoint, rate of graft loss, or death at three months was 15.4% and the biopsy-confirmed acute rejection was 42.3%. Death or graft loss at 12 months in the DGF and non-DGF arms was 36.0% and 25.9%, respectively. The mean estimated creatinine clearance at three months was 63 and 55 mL/min in the non-DGF and DGF groups, respectively, while at 12 months it was 56 mL/min in both the groups. Although there was no comparator arm, the results from this exploratory study (compared with data from other phases II and III trials) indicated no apparent benefits of FTY720-based regimens for prevention of acute rejection and preservation of renal function in renal transplant recipients at high risk of DGF.

A phase I/II randomized open-label multicenter trial of efalizumab, a humanized anti-CD11a, anti-LFA-1 in renal transplantation.

Leukocyte function associated antigen-1 (LFA-1) has a multifaceted role in the immune response, including adhesion and trafficking of leukocytes, stabilizing the immune synapse of the MHC-TCR complex and providing costimulation signals. Monoclonal antibodies to the CD11a chain of LFA-1 have been seen to result in effective immunosuppression in experimental models. Efalizumab, a humanized IgG1 anti-CD11a, is approved for use in psoriasis and may provide effective immunosuppression in organ transplantation. Thirty-eight patients undergoing their first living donor or deceased renal transplant were randomized to receive efalizumab 0.5 or 2 mg/kg weekly subcutaneously for 12 weeks. Patients were maintained on full dose cyclosporine, mycophenolate mofetil and steroids or half dose cyclosporine, sirolimus and prednisone. At 6 months following transplant patient survival was 97% and graft survival was 95%. Clinical biopsy-proven acute rejection in the first 6 months after transplantation was confirmed in 4 of 38 patients (11%). Three patients (8%) developed post transplant lymphoproliferative disease, all treated with the higher dose efalizumab and full dose cyclosporine. The two doses of efalizumab resulted in comparable saturation and modulation of CD11a. This phase II trial suggests that efalizumab may warrant further investigation in transplantation.

Exposure-efficacy relationships of a fingolimod-everolimus regimen in kidney transplant patients at risk for delayed graft function.

OBJECTIVE: We explored relationships between blood levels of fingolimod (FTY720) and everolimus versus treated biopsy-proven acute rejection (BPAR) in an open-label trial in de novo kidney transplant recipients. METHODS: Patients (n = 52) who fulfilled predefined criteria placing them at increased risk of delayed graft function received fingolimod 2.5 mg/d, everolimus 2 mg twice daily with trough blood levels (C0) adjusted to 4 to 8 ng/mL, and corticosteroids. Everolimus and fingolimod C0 were collected over 1 year; efficacy readout was at 3 months. RESULTS: Fingolimod C0 accumulated over the first 3 months with a time-averaged level (C0avg) of 5.7 +/- 3.5 ng/mL. At steady state in months 3 to 12, C0 was 7.0 +/- 4.4 ng/mL. Overall, 30 patients (58%) were free from BPAR to month 3. Patients were divided into four groups based on whether their fingolimod C0avg and everolimus C0avg were above or below the population medians. Freedom from BPAR was 53% and 57% for low fingolimod combined with low and high everolimus, whereas the percentages were improved to 83% and 85% for high fingolimod combined with low and high everolimus. CONCLUSIONS: This pilot study with an everolimus-fingolimod regimen demonstrated trends in freedom from rejection that were drug concentration-related and that underscored, in particular, a strong contribution to efficacy from fingolimod.

The evolving experience using everolimus in clinical transplantation.

Everolimus is a derivative of sirolimus, a macrocyclic lactone, originally isolated from Streptomyces hygroscopicus. Both everolimus and sirolimus have a similar mechanism of action, exerting potent inhibition of growth factor-induced proliferation of lymphocytes, as well as other hematopoietic and nonhematopoietic cells of mesenchymal origin. Each agent complexes with the FK506 binding protein 12 to inhibit cyclin dependent kinase(s), collectively termed the target of rapamycin (TOR), causing G1-S phase cell cycle arrest. Safety and efficacy have been documented in large-scale, blinded, randomized, international clinical renal and cardiac transplant trials. Everolimus is more hydrophilic, exhibits a shorter elimination half-life (approximately 30 hours), and demonstrates greater relative bioavailability compared to sirolimus. However, similar to the calcineurin inhibitors and sirolimus, everolimus is biotransformed by the cytochrome P450, 3A4 isozyme. Also similar to sirolimus, clinical experiences identified biologically relevant side effects including hyperlipidemia and exacerbation of cyclosporine (CsA)-associated nephrotoxicity. However, also similar to sirolimus, accumulating evidence suggests that the hyperlipidemia can be controlled and the CsA-associated renal effects appear reduced with a low incidence of acute rejection when everolimus is administered in combination with reduced CsA doses. The experience using everolimus in cardiac transplantation has also provided potentially important insights into the consequences of antiproliferative effects on vascular smooth muscle cells and fibroblasts where reduction in intimal expansion was identified by intravascular coronary ultrasound examination among those patients receiving everolimus. Therefore, available results suggest that the introduction of everolimus as the newest TOR inhibitor should enhance therapeutic options for immunosuppression after organ transplantation.

Sirolimus-based immunosuppression with reduce dose cyclosporine or tacrolimus after renal transplantation.

Sirolimus (SRL), a fermentation product of Streptomyces hygroscopicus, complexes with the FKBP12 to inhibit cyclin dependent kinase(s), collectively termed the target of rapamycin (TOR), causing G(1)-S phase cell cycle arrest. Safety and efficacy have been documented in clinical renal transplantation, but concerns were raised due to important biologically relevant side effects. Hyperlipidemia was identified, beginning with early clinical experiences, and the unexpected findings that SRL may exacerbate CsA associated nephrotoxicity was observed during the pivotal phase III studies. This report details results of our experience using SRL (target trough concentration, 10-15 ng/mL) with low dose CsA (target trough concentration, 50-100 ng/mL), seeking to determine whether this approach might provide effective immunosuppression while reducing associated nephrotoxicity. Among 121 renal transplant recipients, 62 received the SRL based regimen and 59 received MMF with all patients receiving CsA and prednisone. Similar to earlier clinical experiences, hematopoeitic abnormalities and hyperlipidemia were observed among patients who received SRL, and those abnormalities were readily controlled. However, unlike observations from the phase III SRL studies, renal function was not adversely affected. These findings support the growing body of evidence indicating that SRL based immunosuppression in combination low dose calcineurin inhibitors and corticosteroids is safe, efficacious, and without associated renal toxicity.

Aspergillus vertebral osteomyelitis after simultaneous kidney-pancreas transplantation.

Aspergillus osteomyelitis is a rare complication of invasive aspergillosis after organ transplantation. This is the report of a 46-year-old man who underwent a simultaneous pancreas and kidney transplantation, complicated by an Aspergillus osteomyelitis and diskitis of the lumbar spine. Prompt diagnosis with needle biopsy, followed by antifungal therapy using caspofungin, a new antifungal agent recommended for the treatment of refractory aspergillosis, in combination with amphotericin B and an early surgical intervention led to clinical resolution of the infection. Reported cases of spinal aspergillosis after transplantation are reviewed in terms of clinical presentation, risk factors, therapeutic options, and outcome.

Multicenter evaluation of a polyurethaneurea vascular access graft as compared with the expanded polytetrafluoroethylene vascular access graft in hemodialysis applications.

OBJECTIVES: The purpose of this study was to compare in a randomized, prospective, and controlled study, the performance of a multilayered, self-sealing polyurethane vascular access graft (PVAG) and expanded polytetrafluoroethylene (ePTFE) vascular access grafts in hemodialysis applications. Performance measures included graft survival, complications, time to early cannulation, and hemostasis times after cannulation. STUDY DESIGN: A total of 142 patients were randomized equally to receive one of the two grafts after meeting all eligibility requirements. All patients were followed up prospectively to 12 months or to the end of secondary patency. Specifically, this study documented the performance of the PVAG and ePTFE grafts by determining the patencies and complications for both grafts. RESULTS: Patient characteristics between the two groups were similar with respect to risk factors and demographic characteristics (P >.05). Life-table patencies from the date of first dialysis were primary patency: PVAG 55% versus ePTFE 47% (6 months) and PVAG 44% versus ePTFE 36% (12 months) and secondary patency: PVAG 87% versus ePTFE 90% (6 months) and PVAG 78% versus ePTFE 80% (12 months). None of these differences were significant (P >.05). Both primary and secondary patencies were also not significantly different when the date of implantation was the starting point. Adverse events and complications were similar for the two groups, except the PVAG group had a higher incidence of technical complications manifested by graft kinking when compared with the control cohort (P <.05). Additionally, there was no significant difference in complication rates between these two groups with regard to infection and bleeding. When the time to hemostasis after cannulation was compared at 5minutes or less, there were more PVAG cannulation sites that achieved hemostasis compared with ePTFE sites, and this difference was significant (P <.0001). When time to first dialysis access was compared between the two grafts, 53.9% of all PVAG grafts were cannulated before 9 days versus none with the ePTFE grafts (P <.001). However, long-term graft survival was not significantly different when PVAG patients were stratified into early (< 9 days) and the late access (9 >/= days) groups (P =.29). CONCLUSIONS: The PVAG graft allows for early access without compromising long-term performance. Both PVAG and standard ePTFE grafts have similar long-term outcomes, despite early access with the PVAG vascular access grafts.

Human T cells infiltrate and injure pig coronary artery grafts with activated but not quiescent endothelium in immunodeficient mouse hosts.

BACKGROUND: We have previously demonstrated that human artery grafts transplanted to immunodeficient mice are infiltrated and injured by unsensitized allogeneic human T cells. We extended our investigations to human anti-porcine xenoresponses in this model. METHODS: Pig coronary artery segments were interposed into the infrarenal aorta of severe combined immunodeficiency/beige mice. After 7 days, certain recipients were reconstituted with human leukocytes and/or treated with proinflammatory cytokines. The grafts were harvested after 1-70 days and examined by histology, immunohistochemistry, and morphometry. RESULTS: Pig artery grafts from untreated mice had no evidence of injury, leukocytic infiltrate, or endothelial cell activation up to 70 days postoperatively, despite deposition of murine complement. Host reconstitution with human peripheral blood mononuclear cells resulted in a discrete population of circulating T cells that did not infiltrate or injure the grafts up to 28 days after adoptive transfer. Administration of porcine interferon-gamma for up to 28 days sustained the expression of graft vascular cell adhesion molecule-1 and major histocompatibility complex antigens, but did not initiate recruitment of human leukocytes. In contrast, treatment with human tumor necrosis factor for 7 days induced the de novo expression of porcine E-selectin by graft endothelial cells and elicited human T cell infiltration and human peripheral blood mononuclear cell-dependent vascular injury. CONCLUSIONS: The human peripheral blood mononuclear cell-severe combined immunodeficiency/beige mouse model identifies a significant difference between human T cell allogeneic and xenogeneic responses in vivo. Xenografts with quiescent endothelium are not infiltrated or injured by T cells under the same conditions in which allografts are rejected. Activation of pig coronary artery endothelial cells by human tumor necrosis factor, but not porcine interferon-gamma, elicits cellular xenoresponses.

RAD in de novo renal transplantation: comparison of three doses on the incidence and severity of acute rejection.

BACKGROUND: The effects of three doses of RAD (40-O-[2-hydroxyethyl]-rapamycin), a novel macrolide with potent immunosuppressive and antiproliferative properties, on the incidence and severity of acute rejection episodes as well as its tolerability were evaluated in a dose-ranging study in de novo renal transplant recipients. METHODS: In this double-blind, parallel group, multicenter study, recipients were randomized to receive 1 mg, 2 mg, or 4 mg/day of RAD in combination with Neoral (cyclosporine, USP MODIFIED) and corticosteroids. The incidence and severity of biopsy-proven acute rejection episodes, graft survival, patient survival, infection rates, laboratory measurements, and adverse events were compared across groups after 6 months of therapy. RESULTS: Among the 103 recipients, patients receiving 1, 2, or 4 mg/day experienced a 32.4%, 14.7%, or 25.7% incidence of biopsy-proven acute rejection episodes within the first 6 months posttransplantation, respectively. Even though the study was not powered to demonstrate efficacy, the incidence of moderate and severe acute rejection episodes was found to be significantly lower among patients in the 2 mg and 4 mg/day groups than in the 1 mg/day group (P=0.002 and P=0.006, respectively). Overall graft and patient survival rates were excellent. RAD was generally well tolerated. Although blood lipid levels increased in all groups, changes were manageable with lipid-lowering agents and did not warrant discontinuation of study medication. The incidence of viral and fungal infections was low; however, it was higher among recipients treated with 4 mg/day. CONCLUSIONS: In combination with Neoral and corticosteroids, RAD doses of 2 mg and 4 mg/day resulted in lower rates of acute rejection episodes and efficacy failure than the 1 mg/day dose and were significantly more effective in reducing the severity of rejection. Large-scale, controlled, follow-up studies are currently in progress to confirm these initial findings.

Temporal changes of cytokines and nitric oxide products in urine from renal transplant patients.

BACKGROUND: Acute rejection and urinary tract infection (UTI) both increase nitric oxide synthase (NOS) activity in urine from renal transplant patients. Also, with rejection, a regulatory interplay between nitric oxide (NO) and cytokines has been suggested. Thus, measurement of the temporal changes of NOS products and cytokines in urine will provide a strategy for the diagnosis of acute rejection and for its differentiation from UTI. METHODS: Soluble interleukins (ILs) and NOS-related products, cyclic GMP (cGMP), nitrate, and nitrite were measured in 192 urine samples consecutively collected from 13 patients within the first three months of transplantation. Sixty-seven additional urine specimens were collected randomly from 24 patients for follow-up analysis of the nitrate test. RESULTS: Among patients who experienced rejection, the percentage (%) binding of IL-2 increased within the first five days (P = 0.0004) after transplantation and one to five days prior to the clinical diagnosis (dx) of rejection (P = 0.02). Tumor necrosis factor-alpha, IL-6, and IL-8 increased at the time of rejection dx (P < or = 0.01). With UTI, IL-2 (P = 0.01) decreased one to five days prior to dx, and IL-10 (P = 0.003) increased one to five days after dx. Although cGMP and nitrate are dependent variables, cGMP increased (P < or =0.0009) with both rejection and UTI, and nitrate increased (P = 0.0001) with rejection and decreased (P = 0.0001) with UTI. Prior to formal dx (1 to 5 days), urine nitrate clearly differentiated rejection (3004 to 7451 micromol/L) from UTI (90 to 885 micromol/L) and controls (1059 to 3235 micromol/L). The additional 67 urines demonstrated that the sensitivity of the nitrate test for rejection and UTI was 100%. CONCLUSIONS: In renal transplant patients, specific temporal changes in urine cytokine levels do occur with acute rejection and UTI, but urine nitrate levels are the most precise at differentiating rejection from UTI.

Human TNF can induce nonspecific inflammatory and human immune-mediated microvascular injury of pig skin xenografts in immunodeficient mouse hosts.

TNF activates endothelial cells to express cell surface molecules that are necessary to recruit a local infiltrate of leukocytes. Because the actions of this proinflammatory cytokine are not species restricted, we investigated whether human TNF can up-regulate porcine endothelial adhesion molecules to elicit human T cell infiltration and damage of pig skin xenografts in a chimeric immunodeficient mouse model. We have previously demonstrated the vigorous rejection of human skin allografts and the absence of injury to porcine skin xenografts in human PBMC-SCID/beige mice. Intradermal administration of human TNF at high doses (600 or 2000 ng) caused nonspecific inflammatory damage of pig skin grafts, whereas low concentrations of TNF (60 or 200 ng) resulted in human PBMC-dependent injury of porcine endothelial cells. There was a strong correlation among pig skin xenograft damage, human T cell infiltration, and the TNF-induced up-regulation of swine MHC class I and class II molecules, VCAM-1, and, in particular, the de novo expression of porcine E-selectin. The microvascular damage and leukocytic infiltration elicited by TNF were enhanced by porcine IFN-gamma, suggesting that xenografts may be less prone to cytokine-mediated injury due to the species-restricted effects of recipient IFN-gamma. Our results indicate that maintenance of a quiescent endothelium, which does not express E-selectin or other activation-dependent adhesion molecules, is important in preventing human anti-porcine T cell xenoresponses in vivo and that TNF signaling molecules and TNF-responsive gene products are appropriate therapeutic targets to protect against human T cell-mediated rejection of pig xenografts.

Reduced incidence of Epstein-Barr virus-associated posttransplant lymphoproliferative disorder using preemptive antiviral therapy.

BACKGROUND: Posttransplant lymphoproliferative disorder (PTLD) has been observed with increasing frequency consequent to the availability of more effective and potent immunosuppression. Prior work suggested that a peripheral blood monitoring strategy detecting peripheral B lymphoproliferation was effective in the early diagnosis of PTLD among 7 of 179 (3.9%) consecutive transplant recipients. Each of those seven patients received at least one course of antithymocyte globulin, Minnesota antilymphocyte globulin, or OKT3 before developing PTLD. METHODS: To determine whether antiviral prophylaxis might reduce the incidence of PTLD, a subsequent group of 198 consecutive recipients received either ganciclovir or acyclovir during antilymphocyte antibody administration. When the donor or recipient were cytomegalovirus-seropositive, ganciclovir was given; acyclovir was used when both were cytomegalovirus-seronegative. Baseline and protocol posttransplant cell surface profiles were obtained using immunofluorescence and flow cytometry to detect T cells, lymphocyte activation markers, and the CD19 B cell antigen. RESULTS: Demographic factors, including the incidence of recipients more than 50 years of age, non-Caucasians, previous transplantation, and diabetes mellitus, were similar in both groups. Additionally, the number of patients receiving antilymphocyte preparations was similar. However, only one patient (0.5%) from the latter group who received preemptive antiviral therapy developed PTLD. Although elevations in CD19+ B cells preceded clinical PTLD among each of the seven earlier patients, evidence of peripheral B cell proliferation was not demonstrated for the sole patient from the latter group, which suggests a possible effect of antiviral therapy. CONCLUSIONS: Prophylactic antiviral therapy may reduce the sensitivity of peripheral monitoring for B lymphoproliferation, but the dramatic reduction in PTLD incidence strongly supports its use among transplant recipients at risk.

Pig but not human interferon-gamma initiates human cell-mediated rejection of pig tissue in vivo.

Split-thickness pig skin was transplanted on severe combined immunodeficient mice so that pig dermal microvessels spontaneously inosculated with mouse microvessels and functioned to perfuse the grafts. Pig endothelial cells in the healed grafts constitutively expressed class I and class II major histocompatibility complex molecules. Major histocompatibility complex molecule expression could be further increased by intradermal injection of pig interferon-gamma (IFN-gamma) but not human IFN-gamma or tumor necrosis factor. Grafts injected with pig IFN-gamma also developed a sparse infiltrate of mouse neutrophils and eosinophils without evidence of injury. Introduction of human peripheral blood mononuclear cells into the animals by intraperitoneal inoculation resulted in sparse perivascular mononuclear cell infiltrates in the grafts confined to the pig dermis. Injection of pig skin grafts on mice that received human peripheral blood mononuclear cells with pig IFN-gamma (but not human IFN-gamma or heat-inactivated pig IFN-gamma) induced human CD4(+) and CD8(+) T cells and macrophages to more extensively infiltrate the pig skin grafts and injure pig dermal microvessels. These findings suggest that human T cell-mediated rejection of xenotransplanted pig organs may be prevented if cellular sources of pig interferon (e.g., passenger lymphocytes) are eliminated from the graft.

Pharmacokinetic and phase I trial of intraperitoneal carboplatin and cyclosporine in refractory ovarian cancer patients.

PURPOSE: The feasibility and pharmacokinetics of cyclosporine (CsA) delivered intraperitoneally (IP) have not been previously explored. We performed a pharmacokinetic study of IP CsA followed by a phase I dose-escalation trial of the combination of IP CsA and carboplatin in refractory ovarian cancer patients. PATIENTS AND METHODS: A pilot study was performed of three patients who received 1, 10, and 20 mg/kg IP CsA alone. Subsequently, a phase I trial of 35 patients was performed between April 1990 and April 1993. Whole-blood and IP fluid CsA concentrations were measured at serial time points. The highest dose delivered IP was 34.6 mg CsA/kg in combination with carboplatin (250 mg/m2 or 300 mg/m2, depending on creatinine clearance), which was not dose-escalated. The area under the concentration-time curve (AUC) for CsA and half-life (T1/2) were calculated. Objective and serologic responses were noted, and toxicity was graded using the National Cancer Institute common toxicity criteria. RESULTS: The feasibility of delivering IP CsA alone was established. We observed a 1,000:1 ratio between IP fluid and blood concentrations at 20 mg CsA/kg. Pharmacokinetic analysis confirmed that at 20 mg CsA/kg, there was an IP fluid-to-blood AUC ratio of 600:1 in favor of peritoneal exposure. At the highest dose delivered, 34.6 mg CsA/kg, the mean IP CsA levels of 1,110 micrograms/ mL were tolerated moderately well and the IP fluid-to-blood ratio of 1,000:1 was maintained. Blood and IP CsA concentrations were analyzed in the presence and absence of IP carboplatin. At 20 mg CsA/kg, there was no difference in either mean blood CsA levels (0.9 microgram/ mL) or mean IP CsA concentrations (1,000 micrograms/mL) obtained in the absence or presence of carboplatin. The most common toxicity in the phase I study was anemia, seen in 66% of patients. Common toxicities at the maximum CsA dose delivered (34.6 mg/kg) were anemia, leukopenia, thrombocytopenia, and hypertension. In this trial, three objective responses (two complete and one partial) were observed for a duration of 3 to 11 months. Control of platinum-resistant ascites was an important feature, noted in five of eight patients. CONCLUSION: We have established the feasibility of delivering IP CsA up to doses of 34.6 mg/kg in conjunction with carboplatin, and the sustaining of IP fluid to blood ratios of 1,000:1. The IP administration of CsA resulted in a favorable ratio of exposure for the peritoneal cavity compared with systemic exposure, indicating a therapeutic advantage of this approach with a significant decrease in systemic toxicity. We recommend that 34.6 mg/ kg of IP CsA be tested as a phase II dose in combination with carboplatin in refractory ovarian cancer patients. This report provides the groundwork for future studies using IP CsA, both as a chemomodulator of platinum and of multidrug resistance.

Must living renal donors be hospitalized overnight prior to surgery?

To determine whether preoperative intravenous hydration was an important determinant of perioperative safety for the kidney donor or of early allograft function, 21 consecutive living donor transplants were assessed retrospectively. Donors hospitalized overnight received 1008 +/- 169 mL of intravenous fluid during the 8 h prior to operation, compared to no preoperative hydration among a cohort of 15 patients. No differences between intraoperative blood pressures, fluid administration, urine output, or time in the operating room were identified between groups. Postoperative allograft function was not compromised by the lack of hydration. We conclude that living kidney donors can safely undergo elective nephrectomy without prior intravenous hydration.

Phase I trial of intravenous carboplatin and cyclosporin A in refractory gynecologic cancer patients.

Our objective was to determine the maximum tolerated dose of cyclosporin A (CsA) delivered as a loading dose (LD) and continuous i.v. infusion (CI) in combination with carboplatin in patients with refractory gynecologic cancers. Twenty-nine heavily pretreated patients (25 ovarian epithelial, 2 cervical, and 2 endometrial carcinomas) received 113 cycles of CsA and carboplatin from September 1989 to September 1991. Twenty-four of these 29 carcinomas were strictly defined to be platinum resistant. CsA was administered as a LD escalated from 6 to 10 mg/kg followed by a 24-h CI from 2.5 to 14.5 mg/kg/day. Carboplatin was targeted to an area under the time versus concentration curve (AUC) of 6 mg/ml x min and was not dose escalated. Whole-blood CsA concentrations (fluorescence polarization immunoassay) at the maximum tolerated dose (10 mg/kg LD, 14.5 mg/kg/day CI) ranged from 2.4 to 3.0 microgram/ml over 12 h. Estimated median carboplatin AUC, based on calculated carboplatin clearance, was 7.9 mg/ml x min. The dose-limiting toxicity of the combination of CsA and carboplatin was grade 4 thrombocytopenia. Grade 3 or 4 thrombocytopenia occurred in 35% of the patients, which could be explained by the effects of carboplatin (AUC of 6 mg/ml x min) alone. Overall, neutropenia occurred in 24% of the patients and anemia in 17% of the patients. Grade 3 or 4 nausea or vomiting was noted in 10 and 14% of the patients, respectively. Grade 3 hypertension during CsA administration occurred in 14% of the patients. No grade 3 or 4 nephrotoxicity was seen in this trial. Three objective responses were noted: one complete response (11 months) and one partial response (5 months), both in potentially platinum-sensitive patients with platinum-free intervals of only 9 months each. One platinum-resistant patient had a partial response for 21 months. Five additional patients experienced >75% reduction of CA-125 or a return to a normal CA-125 titer. We concluded that whole-blood CsA concentrations of >3.0 microgram/ml (as seen when CsA is used as a modulator of multidrug resistance) were not achievable in this combination with carboplatin in this population of heavily pretreated gynecologic cancer patients. However, because CsA is used in this trial as a chemosensitizer in platinum-sensitive tumors and as a chemomodulator of platinum resistance, we targeted a CsA concentration of >1.0 microgram/ml, which was achieved. The CsA dose recommended for a Phase II trial of this combination is 10 mg/kg LD and 11.6 mg/kg/day CI, which results in blood CsA concentrations ranging from 1.2 to 1.3 microgram/ml over 12 h. Responses in this population of refractory gynecologic cancer patients are unusual, and these encouraging results form the basis for a Phase II trial of this combination.