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R Storb

Publications and source records attributed to R Storb.

At least 289 records · Page 16Linked to original sources

Summarizing data on survival, relapse, and chronic graft-versus-host disease after bone marrow transplantation: motivation for and description of new methods.

Kaplan-Meier curves are frequently used to summarize survival, relapse, and chronic graft-versus-host disease (GVHD) data in the bone marrow transplant setting. Some fundamental problems with the use of Kaplan-Meier curves for the summary of relapse and GVHD are described. Alternatively, the use of simple probability and conditional probability curves for summarizing relapse incidence and transplant-related mortality is illustrated with previously published data from a randomized clinical trial. Prevalence curves provide an appropriate alternative for the summary of a transient condition such as chronic GVHD. When combined with Kaplan-Meier curves for survival and/or relapse-free survival, these methods provide a more accurate and comprehensive summary of the various marrow transplant outcomes. These methods of display are also applicable to other settings where more than one type of treatment failure can occur and where follow-up time may be variable.

Bone Marrow Transplantation↗

Recombinant granulocyte-macrophage colony stimulating factor followed by immunosuppressive therapy for aplastic anaemia.

Seventeen patients with aplastic anaemia were treated with recombinant human granulocyte-macrophage colony stimulating factor (rhGM-CSF) for 14 d. Nonresponding patients were then treated with anti-human thymocyte globulin (ATG), methylprednisolone and oxymetholone. Side-effects of rhGM-CSF included fever, nausea and vomiting, diarrhoea, bone pain, headache and chills. Two patients had sustained trilineage haemopoietic recovery after receiving only rhGM-CSF. Of 11 patients who received immunosuppressive therapy, there was one complete response, two partial responses, one minimal response, and seven nonresponses. Actuarial survival at 2 years is 64%. Early administration of rhGM-CSF had no apparent effect on subsequent response to immunosuppressive therapy.

Adolescent↗

Inhibition of canine NK activity by anti-CD18 monoclonal antibody, UV irradiation and cyclosporine.

Previous studies from our laboratory have shown that large granular lymphocytes (LGL) mediate natural killer cell (NK) activity in dogs and that host LGL are associated with graft failure in a canine model of histoincompatible marrow transplantation. We now report studies on the effects of anti-CD18 monoclonal antibody (MAB) 60.3, ultraviolet (UV) irradiation and cyclosporine (CSP) on in vitro canine NK function. Treatment with the murine anti-CD18 MAB 60.3 produced marked diminution in lytic function (mean 79% inhibition). UV irradiation at doses greater than 1.6 millijoules/cm2 completely eliminated NK function; this effect was not due to defective effector/target conjugate formation. CSP also inhibited NK function, although in vitro lytic activity was not completely blocked (mean of 44% inhibition) at concentrations which correspond to those achieved in vivo (400 ng/mL). These observations form a basis for future investigations aimed at preventing graft failure in the canine model of histoincompatible marrow transplantation by blocking NK function in vivo.

Animals↗

Acute graft-versus-host disease and the risks for idiopathic pneumonia after marrow transplantation for severe aplastic anemia.

The risks for the development of idiopathic pneumonia after allogeneic BMT were assessed in a case-series review at a single marrow transplantation center. All allogeneic marrow recipients (n = 299) (age range 1-60 years) with severe aplastic anemia (SAA) transplanted from family member donors after conditioning with CY were evaluated. Post-grafting immunosuppression consisted of MTX alone in 205 patients (69%), CY alone in 16 (5%) and a combination of the two in 78 (26%). The incidence estimate for any pneumonia within the first 200 days after transplant was 18% (95% confidence interval = 14-24%). Of 48 cases of pneumonia, CMV infection was documented in 44%, 21% were idiopathic and the remainder were either due to other infections or were not evaluated. The effect of acute GVHD on the incidence of pneumonia was examined using multivariate Cox proportional hazards models which included covariates for potential confounding factors. Consistent with previous reports, acute GVHD was associated with an increased incidence of any pneumonia (relative risk (RR) = 3.5, 95% Cl = 1.9-6.9; p < 0.001). Specifically, acute GVHD also was associated with the largest risk of idiopathic pneumonia (RR = 5.0, 95% Cl = 1.1-22; p = 0.04). In conclusion, recognition of acute GVHD as a risk factor for idiopathic pneumonia suggests that mechanisms in addition to chemoradiation damage are responsible for non-infectious lung injury after BMT.

Acute Disease↗

Splenectomy does not enhance engraftment of DLA-nonidentical marrow transplants.

Previous studies in mice and monkeys suggested that either splenic irradiation of splenectomy led to enhanced allogeneic marrow engraftment. These findings suggested that a population of radiation-resistant host cells involved in mediating marrow graft rejection are sequestered in the spleen. In this current study, the effect of splenectomy in dogs receiving 9.2 Gy total body irradiation (TBI) and unrelated dog leukocyte antigen (DLA)-nonidentical donor marrow grafts was studied. We found that splenectomy did not significantly change the incidence of graft failure as compared to that observed in previously and concurrently transplanted nonsplenectomized recipients.

Animals↗

Use of granulocyte-macrophage colony-stimulating factor and erythropoietin in combination after autologous marrow transplantation.

The toxicities and possible utility of the combination of recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) and recombinant human erythropoietin (rHuEPO) given after autologous BMT were evaluated in this pilot trial. Eighteen patients received the combination and were compared with six concurrent control and 65 historical control patients treated with rhGM-CSF alone. Patients treated with the combination tended to have more rapid recovery to an absolute neutrophil count of 500 x 10(6)/l (median = 12.5 vs 18 days for concurrent and 19 days for historical control patients). There was no apparent impact on red cell transfusion requirements, platelet recovery or duration of hospitalization. Patients treated in the current study with rhGM-CSF plus either rHuEPO or with placebo had a higher incidence of rash than seen in our historical experience using rhGM-CSF. This difference may reflect changes in the source of rhGM-CSF or in the infusion schedule. Erythropoietin can be combined safely with rhGM-CSF after autologous transplantation. Larger controlled trials will be necessary to detect possible therapeutic effects.

Adolescent↗

Consequences of cryopreserving first remission autologous marrow for use after relapse in patients with acute myeloid leukemia.

Ninety-eight patients with AML had marrow harvested and cryopreserved at a median of 6 months (range 1-36 months) after achieving first CR with the intent of performing an ABMT at the first sign of relapse. Thirty-three of the 98 patients have not relapsed and 32 survive at a median of 64 months (range 10-105 months) after marrow storage. Sixty-five of the 98 patients relapsed at a median of 7 months (range 1-53 months) after marrow storage. The survival at 2 and 4 years for the 65 patients who relapsed was 22% and 8% respectively. Sixteen of 24 patients treated initially with chemotherapy were ultimately transplanted and two are surviving 21 and 41 months following ABMT and allogeneic marrow transplant respectively. There were no survivors among the eight patients treated with chemotherapy who were not transplanted. Thirty-eight of the 65 patients who relapsed proceeded directly to ABMT without attempts at remission induction, and eight survive disease-free 15-114 months following ABMT. One of the first 17 patients treated with cyclophosphamide and total body irradiation survives without relapse. The probabilities of relapse-free survival, non-relapse mortality, and relapse for the 17 most recent patients prepared with busulfan-containing regimens were 41%, 39% and 32% respectively. Surviving patients had longer first remissions (p = 0.08) and lower peripheral blood blast counts at the time of transplant (p = 0.02) when compared with patients who died. These data suggest that ABMT in untreated first relapse is a reasonable approach for the treatment of patients with AML who relapse.

Adolescent↗

Specific growth inhibition of primitive hematopoietic progenitor cells mediated through monoclonal antibody binding to major histocompatibility class II molecules.

In a previous study using a canine model, we reported that a certain anti-class II monoclonal antibody (MoAb H81.9), which recognizes an epitope formed by the alpha and beta subunits of HLA-DR, prevented long-term engraftment of autologous marrow cells if administered intravenously during the first 4 days after 9.2 Gy of total body irradiation. Another MoAb (B1F6), reactive with only the beta subunit of HLA-DR and -DP, had no adverse effect on engraftment, although both MoAbs detect antigens on hematopoietic long-term repopulating cells as determined from complement-mediated lysis experiments. In the present study, continuous exposure of unfractionated human marrow to MoAb H81.9 specifically inhibited the growth of primitive progenitor cells that require multiple hematopoietic growth factors for proliferation (high proliferative potential colony forming cells [HPP-CFC] and burst-forming units-erythroid [BFU-e]), but had no effect on more mature, single factor responsive (CFU-GM), progenitor cells. In contrast, MoAb B1F6 did not impair primitive progenitor cell growth cultured as unfractionated marrow. However, when cell dose-response experiments were performed using CD34-positive cells plated at low cell densities, the marked inhibitory effects of MoAb H81.9 on HPP-CFC and BFU-e colony formation were not seen. These findings suggest that MoAb H81.9 may not inhibit primitive hematopoietic cells directly, but rather indirectly through the action of potent mediators derived from other HLA-DR-positive marrow cells.

Antibodies, Monoclonal↗

Acute graft-versus-host disease: analysis of risk factors after allogeneic marrow transplantation and prophylaxis with cyclosporine and methotrexate.

Previous studies of risk factors for acute graft-versus-host disease (GVHD) involved patients receiving predominantly single-agent prophylaxis. Therefore, a retrospective analysis was performed on 446 patients, from a single institution, who received transplants of marrow from HLA-identical siblings and the combination of cyclosporine (CSP) and methotrexate (MTX) to determine risk factors for acute GVHD associated with this more effective form of GVHD prophylaxis. The incidences of Grades II-IV and Grades III-IV (severe) acute GVHD were 35% and 16%, respectively. Increased clinical grades of acute GVHD in patients without advanced malignant disease were associated with a decreased survival. In a multivariate Cox regression analysis, risk factors associated with the onset of Grades II-IV acute GVHD were sex mismatch and donor parity (P = .001), increased dose of total body irradiation (TBI) (P = .001), and reduction to less than 80% of the scheduled dose of MTX (P = .02) or CSP (P = .02). The multivariate analysis indicated a relative risk of 1.37 for acute GVHD in a group defined as having advanced malignant disease at transplant; however, this difference failed to reach conventional levels of statistical significance (P = .07). Reduction of MTX and CSP occurred in up to 36% and 44% of patients, respectively, primarily because of renal or hepatic dysfunction. The periods of increased risk for the onset of acute GVHD were up to 1 week after a reduction of MTX and 2 weeks after a reduction in CSP. When only patients who developed Grades II-IV acute GVHD were considered, the more severe acute GVHD of Grades III-IV was associated with increased patient age of 40 years or greater (P = .05) and dose reductions of CSP (P = .008). Serologic status of patient and donor for cytomegalovirus (CMV), HLA antigens in the A and B loci, and isolation in a laminar air flow room during marrow transplantation, all previously identified as risk factors for acute GVHD, were not confirmed as risk factors in this study population. The toxicity of MTX and CSP and the development of acute GVHD from inadequate immunosuppression because of dose reduction warrants further trials with potentially less toxic immunosuppressive agents. Risk factors for acute GVHD should be considered in clinical management and in the design of clinical trials.

Adult↗

Specific marrow ablation before marrow transplantation using an aminophosphonic acid conjugate 166Ho-EDTMP.

166Holmium ethylenediaminetetramethylene phosphonic acid (166Ho-EDTMP) is a short-lived beta-emitting radionuclide complexed to an aminophosphonate ligand that we have investigated in a canine model as a potential agent for specific marrow ablation before marrow transplantation. After intravenous injections, 166Ho-EDTMP distributed principally to bone and after 24 hours the concentrations of 166Ho-EDTMP in bone were more than 200-fold higher than in any other organ. Increasing dosages of 166Ho-EDTMP led to increasingly prolonged and severe myelosuppression, but myeloablation was not achieved. Histologic examination of recovering animals suggested that the spleen may have acted as a reservoir for circulatory hematopoietic precursors. Four splenectomized animals administered 20 to 30 mCi/kg 166Ho-EDTMP without marrow transplantation died with marrow aplasia, while four splenectomized animals administered similar dosages of 166Ho-EDTMP followed by autologous transplantation recovered. The dose-limiting toxicity of 166Ho-EDTMP appeared to be marrow stromal damage resulting in myelofibrosis, which was reversible. These results suggest that 166Ho-EDTMP can be used to specifically ablate marrow function before marrow transplantation.

Animals↗

Immunosuppressive therapy of aplastic anemia: results of a prospective, randomized trial of antithymocyte globulin (ATG), methylprednisolone, and oxymetholone to ATG, very high-dose methylprednisolone, and oxymetholone.

Sixty-eight patients with moderate (n = 15) or severe (n = 53) aplastic anemia were entered into a prospective, randomized, two-arm treatment study comparing antihuman thymocyte globulin (ATG), lower-dose methylprednisolone (LDM) and oxymetholone to ATG, higher-dose methylprednisolone (HDM), and oxymetholone. There were no differences between the two groups when comparing age, sex, etiology of aplasia, disease duration, severity of aplasia, or pretherapy granulocyte counts. Side effects of LDM and HDM were similar. Of the 64 patients evaluable for response to therapy, 12 of 33 (36%) who received LDM had complete, partial, or minimal responses compared with 15 of 31 patients (48%) who received HDM (P = .33). Actuarial survival at 4 years is 43% for patients in the LDM group and 47% for patients in the HDM group (P = .99). Causes of death included hemorrhage, infection, evolution to acute leukemia, and complications of subsequent bone marrow transplantation. Long-term complications included paroxysmal nocturnal hemoglobinuria (n = 3), evolution to myelodysplasia or acute leukemia (n = 6), and recurrent aplasia (n = 6). We were unable to show a significant difference in toxicity, response rate, or survival for patients treated with ATG, oxymetholone, and LDM compared with patients who received ATG, oxymetholone, and HDM.

Adult↗

Phase II trial of recombinant human granulocyte-macrophage colony-stimulating factor in patients undergoing allogeneic bone marrow transplantation from unrelated donors.

The safety and possible efficacy of recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) were evaluated in 40 consecutive patients who received transplants from unrelated donors. rhGM-CSF was administered by 2-hour daily intravenous infusion from day 0 to day 20 or day 27 after the marrow infusion. These patients were compared with 78 historical patients who received transplants from unrelated donors who did not receive rhGM-CSF. The rhGM-CSF-treated patients were older (P = .037) and were treated less frequently in laminar air flow rooms (P = .005) than were control patients. However, the rhGM-CSF-treated group had a higher proportion of "good risk" patients with chronic myelogenous leukemia in chronic phase (P = .006) than did the comparison group (P = .017), rendering comparisons of transplant-related complications not meaningful. rhGM-CSF was well tolerated and did not adversely increase the incidence of graft rejection or increase the incidence and severity of acute graft-versus-host disease. The median day the absolute neutrophil count reached 500/mm3 in patients who received rhGM-CSF was day 21, which was not different from that of historical patients. Nevertheless, the numbers of febrile days and septicemic episodes within the first 28 days in patients who received rhGM-CSF were less than in historical patients. The probability of nonrelapse mortality at 1 year in patients who received rhGM-CSF was 22%. In view of the retrospective nature of the control group, we cannot conclusively determine whether rhGM-CSF administration was beneficial. A prospective, randomized controlled study of rhGM-CSF is required to confirm these suggestive data.

Adult↗