A prospective randomized toxicity study to compare reduced-intensity and myeloablative conditioning in patients with myeloid leukaemia undergoing allogeneic haematopoietic stem cell transplantation.

BACKGROUND: To our knowledge, no randomized toxicity studies have been conducted to compare myeloablative conditioning (MAC) and reduced-intensity conditioning (RIC) in allogeneic haematopoietic stem cell transplantation (HSCT). METHODS: Adult patients ≤60 years of age with myeloid leukaemia were randomly assigned (1 : 1) to treatment with RIC (n = 18) or MAC (n = 19) in this Phase II single-centre toxicity study. RESULTS: There was a maximum median mucositis grade of 1 in the RIC group compared with 4 in the MAC group (P < 0.001). Haemorrhagic cystitis occurred in eight of the patients in the MAC group and none in the RIC group (P < 0.01). Results of renal and hepatic tests did not differ significantly between the two groups. RIC-treated patients had faster platelet engraftment (P < 0.01) and required fewer erythrocyte and platelet transfusions (P < 0.001) and less total parenteral nutrition (TPN) than those treated with MAC (P < 0.01). Cytomegalovirus (CMV) infection was more common in the MAC group (14/19) than in the RIC group (6/18) (P = 0.02). Donor chimerism was similar in the two groups with regard to CD19 and CD33, but was delayed for CD3 in the RIC group. Five-year transplant-related mortality (TRM) was approximately 11% in both groups, and rates of relapse and survival were not significantly different. Patients in the MAC group with intermediate cytogenetic acute myeloid leukaemia had a 3-year survival of 73%, compared with 90% among those in the RIC group. CONCLUSION: Reduced-intensity conditioning had several advantages compared with MAC, including less mucositis, less haemorrhagic cystitis, faster platelet engraftment, the need for fewer transfusions and less TPN, and fewer CMV infections. Both regimens were tolerated and TRM was low.

Evaluation of intervention strategy based on CMV-specific immune responses after allogeneic SCT.

Late occurring CMV disease is an important problem after allogeneic SCT and has been associated with poor CMV-specific immunity. We conducted a prospective study of 58 patients studied at 3-6 months after allo-SCT, to base the antiviral therapy on monitoring of CMV-specific immunity. Reactivation of CMV was measured by quantitative PCR, and intracellular IFN-gamma production was analysed by FACS and enzyme-linked immunospot. Antiviral therapy was deferred in patients with documented CMV-specific immunity without symptoms of CMV disease or severe GVHD. Nineteen episodes of CMV reactivation were assessable. The strategy was correctly applied in 16/19 episodes. Therapy was deferred in 5/19 (none of these patients developed CMV disease) and was given according to the strategy in 11/19 episodes. Two patients received antiviral therapy despite having T cell-specific immunity. There was a tendency that patients with late CMV reactivation had weak CD8 T cell immunity at 3 months (P=0.06). The donors' serostatus influenced the strength of both CD4 and CD8 immunity at 3 months after SCT (P<0.01). There was no effect as regards the type of conditioning, donor type, stem cell source or acute GVHD. Monitoring the immunity of SCT patients may allow more targeted use of antiviral therapy.

Risk factors for fatal infectious complications developing late after allogeneic stem cell transplantation.

Infectious complications remain a major problem contributing to significant mortality after hematopoietic allogeneic stem cell transplantation (HSCT). Few studies have previously analyzed mortality due to late infections. Forty-four patients dying from an infectious complication were identified from a cohort of 688 consecutive patients surviving more than 6 months without relapse. A control group of 162 patients was selected using the year of HSCT as the matching criterion. Out of 44 patients, 30 (68%) died from pneumonia, 7/44 (16%) from sepsis, 5/44 (11%) from central nervous system infection and 2/44 (4.5%) from disseminated varicella. The cumulative incidences of different types of infection were 1.6% for viral, 1.5% for bacterial and 1.3% for fungal infections and 0.15% for Pneumocystis jirovecii pneumonia. The majority (66%) of the lethal infections occurred within 18 months after HSCT. Acute GVHD (relative risk (RR): 7.19, P<0.0001), chronic GVHD (RR: 6.49, P<0.001), CMV infection (RR: 4.69, P=0.001), mismatched or unrelated donor (RR: 3.86, P=0.004) and TBI (RR: 2.65, P=0.047) were independent risk factors of dying from a late infection. In conclusion, infections occurring later than 6 months after HSCT are important contributors to late non-relapse mortality after HSCT. CMV infection or acute GVHD markedly increase the risk.

Fludarabine-based disease-specific conditioning or conventional myeloablative conditioning in hematopoietic stem cell transplantation for treatment of non-malignant diseases.

Fludarabine-based conditioning (FBC) was given to 24 patients and conventional myeloablative conditioning (MC) to 33 patients, most children, before hematopoietic stem cell transplantation (HSCT) for non-malignant diseases. The donors were human leukocyte antigen (HLA)-A, -B, -DRbeta1-identical related (33%) or unrelated (67%). In the FBC group, two grafts failed versus three in the MC group; all were successfully regrafted. Fever was more common in the MC patients (P=0.003). Bacteremia occurred in 25% of the FBC group and 50% in the MC group (P=0.1). In the FBC group, platelet engraftment was faster and transfusions were fewer (P<0.05). Mucositis and renal function were similar in the two groups. The MC group had higher maximum bilirubin (P=0.03) and less often normal spirometry (P=0.04) after HSCT. A 7-year-old girl in the MC group had permanent alopecia. No patients had severe acute graft-versus-host disease (GVHD). Chronic GVHD was rare. Complete donor CD3+ chimerism was more common in the MC group (P=0.01), but CD33+ engraftment was better with FBS (P=0.03). Treatment-related mortality was 4 and 15%, and 5-year survival was 89 and 85% in the FBC and MC groups. Although survival was similar, FBC is a promising alternative to MC in non-malignant disorders.

Impact on the cytomegalovirus (CMV) viral load by CMV-specific T-cell immunity in recipients of allogeneic stem cell transplantation.

Patients experience cytomegalovirus (CMV) reactivation after stem cell transplantation (SCT) and need repeated courses of pre-emptive therapy. Analysis of CMV-specific immunity might help to assess the need for antiviral therapy. Forty-eight patients were studied during the first 3 months after SCT. Peripheral blood lymphocytes were stimulated by CMV antigen, and interferon (INF)-gamma production by CD3+ and CD4+ T cells was analysed. Results were correlated to transplant factors and CMV disease. Patients with INF-gamma production by CD3+ cells at 4 weeks after SCT had lower peak viral loads than patients with no such production (P=0.03). There was a similar tendency as regards CD4+ cells (P=0.09). Patients who underwent reduced-intensity conditioning (RIC) more frequently had CD3+ (48%) and CD4+ immunity (56%) 4 weeks after SCT compared with patients who received myeloablative conditioning (CD3+ 25%; CD4+ 35%). There was no effect of stem cell source, donor type or acute graft-versus-host disease. Three of 48 patients developed CMV disease and none of them had detectable INF-gamma production. CMV-specific T-cell response is associated with a lower rate of CMV replication. RIC results in improved T-cell reconstitution. Recovery of CMV-specific immunity might be delayed in patients with CMV disease. These observations suggest that detection of CMV-specific T-cells is useful in assessing the immunity against CMV.

Leukemia lineage-specific chimerism analysis is a sensitive predictor of relapse in patients with acute myeloid leukemia and myelodysplastic syndrome after allogeneic stem cell transplantation.

One of the major complications after allogeneic stem cell transplantation (SCT) in patients with malignant disease is a high frequency of relapse. We have prospectively analyzed the clinical impact of recipient-derived chimeric cells in 30 patients with acute myeloid leukemia and myelodysplastic syndrome after SCT. In order to improve sensitivity and specificity, all samples were cell-separated by using immunomagnetic beads according to the patient's leukemia phenotype, expressed at diagnosis or relapse before SCT. Twelve out of 30 patients experienced a clinical relapse after SCT. Median follow-up time for patients alive and without relapse (n = 15) was 30 (16-47) months. Mixed chimerism in peripheral blood (PB) and bone marrow (BM) > or =1 month post SCT, in the leukemia-affected cell lineage, was detected in 14/30 patients. Ten of these 14 patients relapsed as compared to 2/16 with donor chimerism (DC) (P <0.01). All eight patients with MC in peripheral blood > or =1 month after SCT relapsed vs 4/22 DC patients (P < 0.001). MC was detected a median of 66 (23-332) days before hematological relapse. No correlation was found between T cell MC and relapse. In this study, chimerism analysis showed a higher sensitivity and specificity vs morphological examination. In conclusion, this study may provide a rational basis for treatment with adoptive immunotherapy at an earlier time after SCT than at present, in patients with AML and MDS, in order to treat recurrences of malignant disease.

Ex vivo T lymphocyte expansion for retroviral transduction: influence of serum-free media on variations in cell expansion rates and lymphocyte subset distribution.

OBJECTIVE: In the setting of allogeneic stem cell transplantation, suicide gene-manipulated donor T cells that can be selectively inactivated in vivo would potentially allow optimal control of the GVL (graft-vs-leukemia)/GVHD (graft-vs-host disease) balance. Retroviral T-cell transduction requires ex vivo cell expansion, which is often achieved by IL-2 and anti-CD3 stimulation. Traditionally, culture media for cell expansion are supplemented with fetal bovine serum (FBS) or human serum. While these sera promote cell growth and viability, they contain uncharacterized elements that may yield inconsistent results from batch to batch. Cell expansion in serum-free media would therefore be preferable. MATERIALS AND METHODS: We compared T-cell expansion rates in three commercially available serum-free culture media (X-VIVO 15, AIM-V, and Cellgro SCGM), with or without the addition of human serum (HS, 5%). We also aimed to evaluate how the in vitro expansion affected the composition of the various T-cell subsets. Buffy-coats from four healthy donors were expanded for 21 days. The media were compared to standard RPMI 1640 medium, supplemented with HS (5%) or FBS (10%). For retroviral transductions, the LN vector carrying the neomycin- resistance gene was used in four additional donors. RESULTS: In our hands, X-VIVO 15 gave the highest rate of serum-free expansion (a median of 79-fold expansion, range 20-117). For serum-free expansion, activation with OKT3 for 21 days gave slightly higher expansion rates than a 5-day course (however, without statistical significance). When serum was added, this discrepancy was not seen. Cytokine analysis (IFN-gamma, IL-10, and IL-4) showed a distinct type1 cytokine pattern with elevated IFN-gamma levels during the whole period of culture. Flow cytometric analyses showed substantial inter-media, but also some inter-donor, variability in T-cell subset compositions. Transduction of cells with the LN vector and G418 selection resulted in a 14-fold increase (range 3-18) for serum-free X-VIVO 15 based cultures. Cell phenotypes remained unchanged by the transduction procedure as compared to nontransduced cells. CONCLUSION: Among the tested serum-free media, X-VIVO 15 has shown to best support the in vitro expansion of T cells, resulting in equal percentages of CD4(+) and CD8(+) cells. These cells can easily be transduced and selected. There seem to be no significant benefits, regarding absolute cell numbers or T-cell subset compositions, with OKT3-stimulation for more than five days. The addition of low levels of HS increases the consistencies in the cell expansion rates for all media.

Does high-dose intravenous immune globulin treatment after bone marrow transplantation increase mortality in veno-occlusive disease of the liver?

Forty-five recipients of bone marrow from HLA-identical siblings were given intravenous immune globulin (IVIG) 0.5 g/kg once a week during the first 3 months after transplantation. Fifty-three consecutive previously transplanted HLA-identical siblings were included as controls. Only patients who were cytomegalovirus (CMV) seropositive or had a CMV-seropositive donor were included. There were no major differences in patient characteristics between the two groups. However, more patients in the IVIG group received individualized graft-versus-host disease (GVHD) prophylaxis with less cyclosporine (P < 0.01), more controls received liposomal amphotericin B (P = 0.01), and more patients in the IVIG group received low-dose heparin as prophylaxis against veno-occlusive disease of the liver (P < 0.001). Median follow-up was 21 months in the IVIG group and 47 months in the control group. There were no differences between the groups with regard to time to engraftment, hospitalization time, or days with fever. No differences between the IVIG group and control group were detected in the incidence of acute GVHD grade II-IV (17% vs. 23%) or chronic GVHD (30% vs. 42%). The incidence of bacterial septicemias (53% vs. 63%) and invasive fungal infections (9% vs. 6%) was unaffected by IVIG treatment. The incidence of symptomatic CMV infection was the same in the two groups (14% vs. 16%). One control patient died of CMV interstitial pneumonitis, and 1 patient from each group died from viral interstitial pneumonitis of other origin. The incidence of veno-occlusive disease (VOD) was 16% in the IVIG group versus 6% in the controls (P = NS). Fatal VOD occurred in 11% of the IVIG group compared with none of the controls (P = 0.02). Other transplant-related complications did not differ between the two groups. Two-year survival was 62% in the IVIG group and 60% in the controls (P = NS). No significant beneficial effect was seen with IVIG, which may increase mortality in VOD. The use of high dose IVIG as prophylaxis in marrow transplant recipients is questioned.

Long-term follow-up of a randomized trial comparing T cell depletion with a combination of methotrexate and cyclosporine in adult leukemic marrow transplant recipients.

Forty-eight adult leukemic recipients of HLA-identical sibling marrow were randomized to T cell depletion using anti-CD8 and anti-CD6 antibodies plus complement (n = 28) or prophylaxis with methotrexate (MTX) and cyclosporine (CsA) (n = 25). Patient characteristics were comparable in the two groups. The median observation time was 5 1/2 years. Transfusions, infections, and acute GVHD did not differ between the groups. Chronic GVHD occurred in 52% of patients receiving T cell-depleted marrow and 23% of those receiving MTX + CsA (P = 0.06). Overall probability of relapse was similar in both groups and actuarial leukemia-free survivals at 5 years were 39% and 35% in the two groups, respectively. Among patients with chronic myeloid leukemia (CML), leukemia-free survival at 5 years was 25% in patients receiving T cell-depleted marrow compared with 51% in those given MTX + CsA (P = 0.09). In patients with acute leukemia the probability of relapse was 24% in the group receiving T cell-depleted marrow compared with 73% in those treated with MTX + CsA (P = 0.06). Leukemia-free survival was 55% and 21% in the two groups, respectively (NS). CML patients tended to have a poorer prognosis and those with acute-leukemia better outcome with T cell depletion than with combined MTX + CsA. It is concluded that T cell depletion is unsuitable for patients with CML, but may be considered in patients with acute leukemia.

Results of different strategies for reducing cytomegalovirus-associated mortality in allogeneic stem cell transplant recipients.

BACKGROUND: Several preventive strategies against cytomegalovirus (CMV) disease have been developed during the last decade. These have frequently been used in combination, and it has been difficult to identify each strategy's contribution. METHODS: Risk factors for CMV disease, death in CMV disease and transplant-related mortality were analyzed in 584 patients, who underwent a total of 594 allogeneic bone marrow transplants. RESULTS: The overall probability of CMV disease was 8.9%. No seronegative patient who had a seronegative marrow donor developed CMV disease. The corresponding probabilities for seronegative patients with seropositive donors, seropositive patients with seronegative donors, and seropositive patients with seropositive donors were 5.4%, 13.7%, and 11.7%, respectively. In multivariate Cox models, the use of preemptive antiviral therapy and being CMV-seronegative reduced the risk for CMV disease, CMV-associated death, and transplant-related mortality (TRM). Patients who received unrelated or mismatched family donor transplants had increased risks for CMV disease, CMV-associated death, and TRM. Older age was a significant risk factor for CMV disease and TRM. A total of 258 patients who were monitored by polymerase chain reaction for CMV DNA were analyzed separately to assess whether addition of another CMV preventive strategy could give benefit. Patients who received mismatched or unrelated donor transplants had increased risk for CMV disease, death in CMV disease, and TRM. High-dose acyclovir prophylaxis or addition of intravenous immune globulin had no influence. CONCLUSIONS: Preemptive therapy based on polymerase chain reaction for CMV DNA was associated with reduced risks for CMV disease, CMV-associated death, and TRM, whereas other prophylactic modalities did not give additional benefit.

Low incidence of acute graft-versus-host disease, using unrelated HLA-A-, HLA-B-, and HLA-DR-compatible donors and conditioning, including anti-T-cell antibodies.

BACKGROUND: Using unrelated bone marrow, there is an increased risk of graft-versus-host disease (GVHD). METHODS: HLA-A-, HLA-B-, and HLA-DR-compatible unrelated bone marrow was given to 132 patients. The diagnoses included chronic myeloid leukemia (n=43), acute lymphoblastic leukemia (n=29), acute myeloid leukemia (n=27), myelodysplastic syndrome (n=4), lymphoma (n=3), myeloma (n=1), myelofibrosis (n=1), severe aplastic anemia (n=12), and metabolic disorders (n=12). The median age was 25 years (range 1-55 years). HLA class I was typed serologically, and class II was typed by polymerase chain reaction using sequence-specific primer pairs. Immunosuppression consisted of antithymocyte globulin or OKT3 for 5 days before transplantation and methotrexate combined with cyclosporine. RESULTS: Engraftment was seen in 127 of 132 patients (96%). Bacteremia occurred in 47%, cytomegalovirus (CMV) infection in 49%, and CMV disease in 8%. The cumulative incidences of acute GVHD > or = grade II and of chronic GVHD were 23% and 50%, respectively. The 5-year transplant-related mortality rate was 39%. The overall 5-year patient survival rate was 49%; in patients with metabolic disorders and severe aplastic anemia, it was 61% and 48%, respectively. The disease-free survival rate was 47% in patients with hematological malignancies in first remission or first chronic phase and 38% in patients with more advanced disease (P=0.04). Acute GVHD was associated with early engraftment of white blood count (P=0.02). Poor outcome in multivariate analysis was associated with acute myeloid leukemia (P=0.01) and CMV disease (P=0.04). CONCLUSION: Using HLA-A-, HLA-B-, and HLA-DR-compatible unrelated bone marrow and immunosuppression with antithymocyte globulin, methotrexate, and cyclosporine, the probability of GVHD was low and survival was favorable.

A new method for in vitro expansion of cytotoxic human CD3-CD56+ natural killer cells.

Adoptive transfer of immunocompetent cells may induce anti-tumor effects in vivo. However, a significant obstacle to the development of successful cellular immunotherapy has been the availability of appropriate cytotoxic cells. Among the immunologic effector cells that are considered mediators of anti-tumor effects, those with the highest per-cell cytotoxic capacity express a natural killer (NK) cell phenotype, i.e., CD56(+)CD3(-). However, such cells are normally present only in low numbers in peripheral blood mononuclear cells (PBMCs), lymphokine activated killer (LAK), and cytokine induced killer (CIK) cell preparations. To optimize the expansion of human NK cells, PBMCs were cultured in different serum free medium supplemented with monoclonal anti-CD3 antibodies and interleukin (IL)-2 at varying concentrations. By using Cellgro stem cell growth medium supplemented with 5% human serum and IL-2 (500 U/ml) cells expanded 193-fold (median, range 21-277) after 21 days, and contained 55% (median, range 7-92) CD3(-)CD56(+) cells. The remaining cells were CD3(+) T cells, 22% (median, range 2-68) of which co-expressed CD56. The expanded cell population lysed 26 to 45% of K562 targets in a 1:1 effector to target ratio, signifying substantial cytotoxic efficacy. The described method is a simple and efficient way of expanding and enriching human NK cells. We have termed these high-yield CD3(-)CD56(+) cells cytokine-induced natural killer (CINK) cells.

Treatment of moderate to severe acute graft-versus-host disease: a retrospective analysis.

Seventy-one patients with moderate to severe acute GVHD after BMT were analysed retrospectively. At the start of therapy 96% of the patients had rashes, 45% liver abnormalities and 54% gut dysfunctions. Forty-four patients (62%) had been treated for grade I GVHD with systemic corticosteroids. First therapy for moderate to severe acute GVHD was with corticosteroids (n = 59), psoralen with ultraviolet light (PUVA) (n = 14), cyclosporin (CsA) (n = 10), antithymocyte globulin (ATG) (n = 7), methotrexate (MTX) (n = 2), monoclonal antibodies (n = 1) or thalidomide (n = 1). In 18 of these patients two or more agents were combined. Resolution of skin disease and evaluable liver and gut disease were seen in 48%, 44% and 47% of cases, respectively. Overall complete resolution was seen in 37%. Thirty-two patients received a second treatment, resulting in complete resolution in 31%. Patients with a complete response had an actuarial transplant-related mortality of 37% compared with 82% or worse for patients with other outcomes (p < or = 0.003). Combined treatment was superior to ATG, but not better than corticosteroids. In multivariate analysis a low total sum severity score was the only factor associated with complete response (p = 0.02). AML diagnosis (p = 0.01) and GVHD of the liver (p = 0.02) were independent risk factors for treatment failure.

Low-dose cyclosporine of short duration increases the risk of mild and moderate GVHD and reduces the risk of relapse in HLA-identical sibling marrow transplant recipients with leukaemia.

Low-dose cyclosporine (CsA), starting at 1 mg/kg/day i.v. with early discontinuation, and four doses of methotrexate (MTX), was given to 82 consecutive leukaemic patients receiving HLA-identical sibling marrow transplants. Retrospective controls (n = 40) received CsA, starting at 5-7.5 mg/kg/day i.v., given for 1 year, and MTX. In the low-dose group, the risk of acute GVHD grades I-II was 78% as compared to 57% among the controls (P < 0.01). The risk of acute GVHD grades III-IV was 2% and 5%, respectively (NS). Chronic GVHD occurred in 60% in the low-dose group and 24% in the controls (P < 0. 001). Extensive chronic GVHD did not differ between the groups (3% vs6%). In multivariate analyses, low-dose CsA was the only factor associated with acute GVHD grades I-IV (P = 0.02). Significant risk factors for chronic GVHD included low-dose CsA (P = 0.002) and CML (P = 0.03). Transplant-related mortality at 3 years post-BMT was 22% and 19%, in the low-dose group and controls, respectively (NS). The probability of relapse was 26% in the low-dose group and 53% in the controls (P = 0.06). In multivariate analysis, high-dose CsA was the strongest risk factor for relapse (P = 0.03). The 3-year relapse-free survival was 58% in the low-dose group and 43% in the controls (P = 0.1).

Is it safe to treat allogeneic stem cell transplant recipients at home during the pancytopenic phase? A pilot trial.

After myeloablative treatment and allogeneic stem cell transplantation (ASCT), patients are kept isolated in the hospital to prevent infections during neutropenia. To date, 22 patients have been given the choice of being treated at home. Eleven could not be treated at home, and they served as controls. Most had haematological malignancies. The donors were 12 HLA-compatible unrelated, nine HLA-identical siblings and one twin. In the home care group, three developed bacteraemia, compared to nine in the controls (P < 0.01). Patients in the home care group had fewer days of total parenteral nutrition (median 3 vs 24, P < 0.001), required fewer erythrocyte transfusions (median 4 vs 8, P = 0.01), fewer days on i.v. antibiotics (median 6 vs 13 days), and on analgesics (median 0 vs 15) than the controls (P < 0.05). Days with fever, time to engraftment, days with G-CSF and acute GVHD were the same in the two groups. Seven of 11 patients treated at home were readmitted to the ward for a median of 3 (0-7) days, due to fever or lack of a caregiver at home. Days to discharge to the out-patient clinic were faster in the group treated at home (median 20 vs 35 days, P < 0.01). Patients who were treated at home enjoyed being active and taking a walk when they felt like it. This preliminary report suggests that home care after ASCT is not only safe, but superior to isolation in the hospital.

The effect of metronidazole on busulfan pharmacokinetics in patients undergoing hematopoietic stem cell transplantation.

Busulfan (Bu) is an important component of some myeloablative regimens prior to stem cell transplantation (SCT). Over the last few years it has been shown that other drugs administered concomitantly can influence Bu pharmacokinetics. In the present study, we compared Bu concentrations (trough levels) in three groups of patients. Group A (n=5) received metronidazole as graft-versus-host disease prophylaxis during Bu treatment. Group B (n=9) received Bu only for 2 days followed by 2 days of Bu and metronidazole. Group C (n=10) was a control group that received Bu without metronidazole. The mean Bu levels for Group A receiving metronidazole during conditioning was significantly (P<0.001) higher (948+/-280 ng/ml), compared to those observed in the control group (507+/-75 ng/ml). In Group B, the administration of metronidazole resulted in a significant (P<0.001) increase in Bu levels (807+/-90 ng/ml) during the last 2 days, compared to 452+/-68 ng/ml during the first 2 days. In Group A, one patient died with multiorgan failure, three experienced veno-occlusive disease (VOD) and one developed hemorrhagic cystitis. Elevated liver transaminases (AST, ALT) and bilirubin were detected in all Group A patients. In Group B, six patients had elevated liver function tests but no VOD was observed. We conclude that metronidazole should not be administered simultaneously with Bu to avoid the high plasma levels of Bu, which may lead to severe toxicity and/or treatment related mortality.

Methotrexate combined with cyclosporin A decreases graft-versus-host disease, but increases leukemic relapse compared to monotherapy.

Forty patients with leukemia receiving HLA-identical sibling marrow and treated with four doses of methotrexate (MTX) in combination with cyclosporin A (CSA) for prevention of graft-versus-host disease (GVHD) were compared with retrospective controls consisting of 57 patients treated with MTX alone and 30 patients treated with CSA alone. Follow-up time ranged from 2.6 to 6.7 years after bone marrow transplantation. Patients in the MTX + CSA group were older and received a smaller marrow cell dose, but were otherwise comparable regarding disease status, donor/recipient sex match and seropositivity for cytomegalovirus (CMV) and other herpes viruses. Engraftment was slowest in the MTX + CSA group and fastest in the CSA group (p = 0.005 vs MTX and p less than 0.001 vs CSA). The incidence of moderate to severe acute GVHD (grade II-IV) was 8% among patients on MTX + CSA and 26% and 47% in the MTX (p = 0.028) and CSA (p = 0.0001) groups respectively. The corresponding figures for chronic GVHD were 25, 42 and 40% (n.s.). The incidence of CMV interstitial pneumonia was 0% in patients treated with MTX + CSA compared to 23% in the MTX treated patients (p = 0.01) and 11% in the CSA treated patients (p = 0.05). The actuarial 3-year survival in the three groups was similar, 56% for the MTX + CSA patients and 53% for both the MTX and CSA patients (n.s.).(ABSTRACT TRUNCATED AT 250 WORDS)

Long-term immunity to poliovirus after vaccination of allogeneic stem cell transplant recipients.

Revaccination with poliovirus after allogeneic stem cell transplant (SCT) is usually effective, but the longevity of this immunity is unknown. Therefore, poliovirus immunity was studied in 134 patients having survived at least 5 years after vaccination. The median follow-up from vaccination was 8 years (1-19 years). In all, 21 (15.6%) patients had become seronegative to at least one of the poliovirus serotypes during follow-up. The estimated probabilities of remaining immune to poliovirus at 5 and 10 years after vaccination were 94 and 94% for subtype 1, 98 and 94% for subtype 2, and 93 and 90% for subtype 3, respectively. In multivariate analysis, the only risk factor for loss of immunity was younger patient age (P < 0.01), and there was a strong trend for patients with chronic GVHD to lose immunity more rapidly (P = 0.07). A total of 14 patients received a booster dose of an inactivated poliovirus vaccine and all responded. We conclude that poliovirus immunity is retained long term after revaccination in most patients after allogeneic SCT.

Foscarnet for pre-emptive therapy of CMV infection detected by a leukocyte-based nested PCR in allogeneic bone marrow transplant patients.

Fifteen allogeneic BMT patients in a phase II study were given foscarnet 60 mg/kg twice daily for 14 days as pre-emptive therapy against CMV disease. CMV infection was diagnosed by a leukocyte-based nested PCR. All 15 patients were evaluable for toxicity. One patient did not fulfill the inclusion criteria of two consecutively positive CMV PCR tests and therefore was not evaluable for efficacy. Thus, 14 of 15 patients were evaluable for development of CMV disease. None of the patients developed CMV disease and all 14 assessable patients had a negative CMV isolation at the end of therapy. None of the 15 patients had to discontinue therapy due to toxicity. Six patients reported mild gastrointestinal disturbances, three patients headaches, and three patients mild urethritis or hemorrhagic cystitis. Serum-electrolyte disturbances were common including abnormal magnesium, potassium and calcium levels. Two patients developed mild serum-creatinine increases requiring adjustment of the foscarnet dosage according to protocol. We conclude that a dosage of foscarnet of 60 mg/kg given twice daily seems to be safe and effective in preventing CMV disease in allogeneic BMT recipients. A study comparing foscarnet and ganciclovir is indicated.