In a multicenter pilot study, 19 patients with severe acute graft-versus-host disease (aGVHD) refractory to conventional therapy and serotherapy with a monoclonal anti-interleukin-2 receptor antibody were treated by in vivo infusion of a monoclonal anti-tumor necrosis factor alpha (TNF alpha) antibody (B-C7). Ten patients were grafted from a genotypically identical sibling, five from an HLA-mismatched family member, and four from an HLA-matched unrelated donor. Before B-C7 treatment, 15 patients had grade IV and four had grade III GVHD. In all cases, patients received cyclosporine/methotrexate as aGVHD prophylaxis. Patients were administered increasing doses of antibody (from 0.1 to 0.4 mg/kg). The antibody was infused in bolus daily for 4 days and then every other day twice (6 doses). No side effects were observed during treatment regardless of the dose level used. Changes in peripheral blood cell counts occurred in 8 of the 19 patients and appeared to be unrelated to B-C7. No truly complete response was observed; eight patients achieved a very good partial response (42.6%) and six a partial response (31.5%). The treatment was ineffective in five patients (26.4%). When present, the response occurred early (less than 3 days). In the 14 responding patients, gut lesions responded best (100%), followed by skin (85%) and liver (35.7%) lesions. In 9 of 11 evaluable patients (81%), GVHD recurred when treatment was discontinued in a median delay of 3 days (range, 2 to 120 days). All except one died from aGVHD. Two patients did not experience GVHD recurrence and are still alive 13 and 18 months post-bone marrow transplantation. This pilot study shows that a monoclonal anti-TNF alpha antibody may be of benefit to some patients with severe refractory aGVHD, but is ineffective to prevent GVHD recurrence in the majority of cases.

Until recently, cryoprecipitate has been the treatment of choice in patients with severe von Willebrand disease (vWD) because it can transiently correct low plasma levels of factor VIII coagulant activity (FVIII:C) and shorten or normalize the prolonged bleeding time (BT), the two laboratory hallmarks of the disease. However, cryoprecipitate may still transmit blood-borne viruses, whereas the development of virucidal methods have rendered plasma concentrates containing FVIII:C and von Willebrand factor (vWF) safer. To establish their potential usefulness in the treatment of vWD, we compared the effect of four virus-inactivated concentrates on FVII:C and vWF plasma levels and the BT (template method) in 10 patients with severe vWD using a crossover randomized design. The concentrates were an intermediate-purity, pasteurized FVIII-vWF concentrate; an intermediate-purity, dry-heated FVIII-vWF concentrate; a solvent/detergent-treated vWF concentrate, containing little FVIII; and a high-purity solvent/detergent-treated FVIII-vWF concentrate. All concentrates were equally effective in attaining normal and sustained levels of FVIII:C postinfusion, although peak levels were more delayed after the vWF concentrate. The effect of concentrates on the BT, however, was less uniform and satisfactory. The pasteurized FVIII-vWF concentrate transiently corrected, completely or partially, the BT in 8 of 10 patients, the dry-heated and solvent/detergent FVIII/vWF concentrates in five, whereas in no patient did the vWF concentrate correct the BT according to the criteria used in this study. These effects on the BT were not related to the plasma levels of ristocetin cofactor activity-attained postinfusion (100 U/dL or more in the majority of patients) or to the multimeric structure of vWF in concentrates (defective in larger multimers in all cases). In conclusion, even though virus-inactivated concentrates can be used to increase FVIII:C levels in patients with severe vWD, none of the concentrates studied by us consistently normalizes the BT in a sustained fashion.

Hepatic veno-occlusive disease (VOD) is a major regimen-related toxicity after bone marrow transplantation (BMT). Endothelial injury, leading to deposition of coagulation factors within the terminal hepatic venules, is believed to be the key event in the pathogenesis of VOD. To evaluate the benefit and the safety of a VOD prophylaxis with anticoagulants, we conducted a prospective randomized trial of continuous infusion of low-dose heparin among 161 patients under-going either allogeneic (n = 79) or autologous BMT (n = 81). Patients were randomized to receive (n = 81) or not receive (n = 80) prophylactic heparin 100 U/kg/d by continuous infusion from day -8 until day +30 post-BMT. Heparin was found to be highly effective in preventing VOD, which occurred in 11 of 80 patients (13.7%) in the control group versus 2 of 81 (2.5%) in the heparin group (P less than .01). Furthermore, none of the 39 patients in the heparin group developed VOD after allogeneic BMT, versus 7 of 38 (18.4%) in the control group (P less than .01). This prophylactic effect was achieved without added risk of bleeding. Indeed, the low-dose heparin we used did not prolong the partial thromboplastin time and did not increase the red blood cell and platelet requirements. It is therefore recommended that heparin prophylaxis be part of early mortality prevention programs after BMT.

Patients with sickle cell anemia were treated with daily doses of hydroxyurea, to assess pharmacokinetics, toxicity, and increase in fetal hemoglobin (Hb) production in response to the drug. Plasma hydroxyurea clearances were not a useful guide to maximum tolerated doses of the drug. The mean daily single oral dose that could be maintained for at least 16 weeks was 21 mg/kg (range, 10 to 35 mg/kg). Among 32 patients, last HbF levels were 1.9% to 26.3% (mean, 14.9%) with increases in HbF over initial values of 1.4% to 20.2% (mean, 11.2%). The most significant predictors of last HbF were last plasma hydroxyurea level, initial white blood count and initial HbF concentration. Last HbF was not related to beta globin haplotype or alpha globin gene number. No serious toxicity was encountered. Clinically significant bone marrow depression was avoided, and chromosome abnormalities after 2 years of treatment were no greater than those observed before treatment. The period of observation has been too short to evaluate the risk of carcinogenesis. Patient's red cells developed striking macrocytosis. Median red cell Hb concentrations did not change. Hb concentrations increased, on average 1.2 g/dL, but serum erythropoietin levels increased. Patients' body weights increased, and some returned to work or school, but no conclusions regarding therapeutic efficacy could be drawn from this uncontrolled open-label study.

The use of cyclosporine-A/methotrexate (CyA/MTX) for graft-versus-host disease (GVHD) prophylaxis is safe and effective for patients undergoing allogeneic bone marrow transplantation after preparation with cyclophosphamide and total body irradiation. We report 87 patients prepared for allogeneic transplant with busulfan 4 mg/kg/d orally for 4 days, followed by cyclophosphamide 60 mg/kg/d intravenously for 2 days (Bu4Cy2). A marked increase in hepatotoxicity was observed in 20 patients administered CyA/MTX, compared with 67 historical control patients who received CyA/methylprednisolone (CyA/MP) for GVHD prophylaxis with all other treatment and support variables remaining constant. The incidence of hyperbilirubinemia (bilirubin greater than or equal to 2 mg/dL) increased from 48% to 80% (P = .02), and the mean maximal bilirubin increased from 4.67 +/- 7.27 to 8.72 +/- 8.73 mg/dL (P = .04), when CyA/MTX was used in place of CyA/MP for GVHD prophylaxis. In addition, the incidence of veno-occlusive disease (VOD) increased from 18% to 70% (P = .0001), and death caused by VOD increased from 4.5% to 25% (P = .02). Survival was not significantly different for the two groups because of a higher non-VOD death rate in patients receiving CyA/MP for GVHD prophylaxis (P = .77). We suggest caution when using Bu4Cy2 in combination with CyA/MTX for GVHD prophylaxis.

There is substantial evidence that the volume of medical procedures in a hospital has an inverse relationship with mortality. We analyzed data for 1313 recipients of HLA-identical sibling bone marrow transplants for early leukemia (acute leukemia in first remission or chronic myelogenous leukemia in first chronic phase) to determine whether transplant outcome differed in small and large centers. Transplants were performed in 86 bone marrow transplant centers active between the years 1983 and 1988, which participated in the International Bone Marrow Transplant Registry. Twenty-one (24%) centers performed five or fewer allogeneic transplants per year during the study period; five (6%) performed more than 40 per year. After adjustment for differences in patient and disease characteristics, the relative risks of treatment-related mortality (1.53, P less than .01) and treatment failure (1.38, P less than .04) were higher among patients who received transplants at centers doing five or fewer transplants per year than among those at larger centers. Among patients receiving transplants in centers performing more than five transplants a year, there was no statistically significant correlation between number of transplants and outcome.

In a phase I study, the sequentially administered combination of recombinant human interleukin-3 (rhIL-3) and rhGM-CSF was compared with treatment with rhIL-3 alone in 15 patients with advanced tumors but normal hematopoiesis. Patients were initially treated with rhIL-3 for 15 days. After a treatment-free interval, the patients received a second 5-day cycle of rhIL-3 at an identical dosage, immediately followed by a 10-day course of rhGM-CSF, to assess the toxicity and biologic effects of this sequential rhIL-3/rhGM-CSF combination. rhIL-3 doses tested were 125, and 250 micrograms/m2, whereas rhGM-CSF was administered at a daily dosage of 250 micrograms/m2. Both cytokines were administered by subcutaneous (SC) bolus injection. rhIL-3/rhGM-CSF treatment was more effective than rhIL-3 but equally effective to each other in increasing peripheral leukocyte counts, especially neutrophilic and eosinophilic granulocyte counts. In contrast, both modes of cytokine therapy raised the platelet counts to the same degree. rhIL-3/GM-CSF treatment was more effective than rhIL-3 in increasing the number of circulating hematopoietic progenitor cells BFU-E and CFU-GM. High-dose rhIL-3, but not low-dose rhIL-3, was as effective as the rhIL-3/rhGM-CSF combinations in increasing the number of circulating CFU-GEMM. The increase in absolute neutrophil counts correlated with the increase in the number of circulating CFU-GM. Side effects, mainly fever, headache, flushing, and sweating, were generally mild, but in two patients the occurrence of chills, rigor, and dyspnea after initiation of GM-CSF treatment necessitated dose reduction and discontinuation, respectively. These results indicate that sequential treatment with rhIL-3 and rhGM-CSF is as effective as single-factor treatment with rhIL-3 in stimulating platelet counts, whereas the effect of combination therapy on neutrophil counts and circulating progenitor cells is superior.

From October 1987 to December 1990, 101 patients with acute myeloid leukemia (AML) were randomized to be transplanted in first complete remission (CR1). Preparative regimen including Cytoxan (120 mg/kg) with total body irradiation (CYTBI) (N = 50) or busulfan (16 mg/kg) (BUSCY) (N = 51) was followed by allogeneic bone marrow transplantation (BMT) from an HLA-identical sibling. Mean time between diagnosis and BMT was 119 days. The outcome for CYTBI at 2 years is better for probability of disease-free survival (DFS) (72% v 47%) (P less than .01), survival (75% v 51%) (P less than .02), relapse (14% v 34%) (P less than .04), and transplant mortality (8% v 27%) (P less than .06). In multivariable analysis, higher relapse and decreased survival and DFS were associated with BUSCY regimen, while chronic graft-versus-host disease also influenced independently the probability of relapse. This demonstrates the present limitation of busulfan use in this setting, possibly due to probable individual variations in biodisponibility. Furthermore, besides the anti-leukemic effect of preparative regimens, this trial points out the progress accomplished in BMT management (transplant mortality = 8% in CYTBI) over the last 20 years as well as the effectiveness of transplant in early first CR after CYTBI (DFS = 72% at 2 years).

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.

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.

DAB486IL-2 is a recombinant fusion toxin in which the native receptor binding domain of diphtheria toxin has been replaced with human interleukin-2 (IL-2). It selectively binds and intoxicates only cells that bear the high-affinity receptor for IL-2. In the first clinical trial of a genetically engineered ligand fusion-toxin, we have treated 18 patients with chemotherapy-resistant IL-2 receptor expressing hematologic malignancies with escalating doses of DAB486IL-2. The maximal tolerated dose of a daily intravenous bolus of DAB486IL-2 was 0.1 mg/kg per day for 10 doses, established by asymptomatic, reversible elevations of hepatic transaminases without changes in other tests of liver function. Other mild reversible side effects noted were rash, nausea, elevated creatinine, chest tightness, and fever. Pharmacokinetic analysis showed a monophasic clearance of 5.8 +/- 0.7 minutes with peak levels of 3,549 +/- 1,041 mg/mL at the 0.1 mg/kg dose. Approximately 50% of patients developed an antibody response to diphtheria toxin or DAB486IL-2. The presence of such antibodies did not preclude patients from experiencing an antitumor response as four of the six patients with antitumor effect had detectable antibody titers. Although this was a phase I trial designed to define the safety of DAB486IL-2, remissions were observed in three patients lasting from 5 to over 18 months. The ability to achieve significant tumor reductions in this group of heavily treated patients is encouraging and suggests additional trials are warranted in hematologic malignancies.

We report the results of a randomized multicenter study comparing the efficacy of antithymocyte globulin (ATG) with that of cyclosporin A (CsA) as first-line therapy for severe aplastic anemia (SAA). Patients were randomized to receive ATG and prednisone (PDN) or CsA; hematologic response and toxicity were compared. At 3-month evaluation, patients who had no or minimal response received the alternative therapy to assess the value of a sequential immunosuppressive therapy for treatment of severe aplastic anemia. One hundred nineteen patients were randomized; 25 were excluded, of whom 3 were misdiagnosed and 22 did not follow the cross-over protocol. Ninety-four patients were analyzed; 46 received CsA, and 48 received ATG-PDN. The actuarial survival was 66.7%, with a median follow-up time of 19 months. There was no significant difference in survival between the groups with, at 3 months, an actuarial survival of 88% in the CsA group and 75% in the ATG group (NS); at 12 months, it was 70% in the CsA group and 64% in the ATG group (NS). The percentage of complete and partial response was 11.6% and 16%, respectively, at 3 months, and 31.6% and 30%, respectively, at 12 months (NS). The main prognostic factor was the absolute neutrophil count (ANC) at entry: Patients with ANC less than 0.2 x 10(9)/L had a significantly lower survival as compared with patients with more than 0.2 x 10(9)/L ANC (P = .0001). At 12 months, 62 evaluable patients were alive, with a complete or partial response in 36 patients. Patients who had responded to the first treatment had a better recovery of bone marrow failure than those who had sequential immunosuppression. The main complication was infection, which was more often observed and more often lethal during ATG and PDN therapy. In this study, initial treatment of SAA with either CsA or ATG-PDN followed by cross-over therapy for nonresponders produced comparable response and survival rates.

Extracorporeal immunoadsorption of plasma to remove IgG and circulating immune complexes (CIC) was evaluated as a therapy for adults with treatment-resistant immune thrombocytopenic purpura (ITP). Seventy-two patients with initial platelet counts less than 50,000/microL who had failed at least two other therapies were studied. They received an average of six treatments of 0.25 to 2.0 L plasma per procedure over a 2- to 3-week period using columns of staphylococcal protein A-silica (PROSORBA immunoadsorption treatment columns; IMRE Corp, Seattle, WA). The treatments caused an acute increase in the platelet count to greater than 100,000/microL in 18 patients and to 50,000 to 100,000/microL in 15 patients. The median time to response was 2 weeks. Responses were transient (less than 1 month duration) in seven of those patients (10%), but no additional relapses were reported over a follow-up period of up to 26 months (mean of 8 months). Clinical responses were associated with significant decreases in specific serum platelet autoantibodies (including anti-glycoprotein IIb/IIIa), platelet-associated Ig, and CIC. Thirty percent of treatments were associated with transient mild to moderate side effects usually presenting as a hypersensitivity-type reaction. Continued administration of failed therapies for ITP, which always included low-dose corticosteroids (less than or equal to 30 mg/d), had no demonstrable influence on the effectiveness of immunoadsorption treatment but did depress the incidence and severity of side effects. The degree of effectiveness of protein A immunoadsorption therapy in patients with treatment-resistant ITP is promising and further controlled studies in this patient population are warranted.

The CD33 antigen, identified by murine monoclonal antibody anti-MY9, is expressed by clonogenic leukemic cells from almost all patients with acute myeloid leukemia; it is also expressed by normal myeloid progenitor cells. Twelve consecutive patients with de novo acute myeloid leukemia received myeloablative therapy followed by infusion of autologous marrow previously treated in vitro with anti-MY9 and complement. Anti-MY9 and complement treatment eliminated virtually all committed myeloid progenitors (colony-forming unit granulocyte-macrophage) from the autografts. Nevertheless, in the absence of early relapse of leukemia, all patients showed durable trilineage engraftment. The median interval post bone marrow transplantation (BMT) required to achieve an absolute neutrophil count greater than 500/microL was 43 days (range, 16 to 75), to achieve a platelet count greater than 20,000/microL without transfusion was 92 days (range, 35 to 679), and to achieve red blood cell transfusion independence was 105 days (range, 37 to 670). At the time of BM harvest, 10 patients were in second remission, one patient was in first remission, and one patient was in third remission. Eight patients relapsed 3 to 18 months after BMT. Four patients transplanted in second remission remain disease-free 34+, 37+, 52+, and 57+ months after BMT. There was no treatment-related mortality. Early engraftment was significantly delayed in patients receiving CD33-purged autografts compared with concurrently treated patients receiving CD9/CD10-purged autografts for acute lymphoblastic leukemia or patients receiving CD6-purged allografts from HLA-compatible sibling donors. In contrast, both groups of autograft patients required a significantly longer time to achieve neutrophil counts greater than 500/microL and greater than 1,000/microL than did patients receiving normal allogeneic marrow. CD33(+)-committed myeloid progenitor cells thus appear to play an important role in the early phase of hematopoietic reconstitution after BMT. However, our results also show that human marrow depleted of CD33+ cells can sustain durable engraftment after myeloablative therapy, and provide further evidence that the CD33 antigen is absent from the human pluripotent hematopoietic stem cell.

The Eastern Cooperative Oncology Group (ECOG) conducted a randomized trial in patients less than or equal to 65 years old (median, 44 years) to determine whether increasing the intensity of postremission therapy in acute myeloid leukemia (AML) would improve the outcome. After uniform induction therapy, patients in complete remission (CR) who were less than 41 years old and who had a histocompatible sibling underwent allogeneic bone marrow transplantation (alloBMT) (54 patients). The remainder of patients in CR were randomized to receive either 2 years of continuous outpatient maintenance therapy with cytarabine and 6-thioguanine (83 patients) or a single course of inpatient consolidation therapy consisting of 6 days of high-dose cytarabine plus 3 days of amsacrine (87 patients). The median duration of follow-up is now 4 years, and patients are included in the analyses of outcome regardless of whether they relapsed before starting the intended treatment. Four-year event-free survival (EFS) was 27% +/- 10% for consolidation therapy versus 16% +/- 8% for maintenance therapy (P = .068) and 28% +/- 11% versus 15% +/- 9% (P = .047) in patients less than 60 years old. The outcome for patients receiving alloBMT was compared with the subset of patients less than 41 years old who received consolidation therapy (N = 29) or maintenance therapy (N = 21). Four-year EFS was 42% +/- 13% for alloBMT, 30% +/- 17% for consolidation therapy, and 14% +/- 15% for maintenance therapy. AlloBMT had a significantly better EFS (P = .013) than maintenance therapy, but was not different from consolidation therapy. In patients less than 41 years old, 4-year survival after alloBMT (42% +/- 14%) did not differ from consolidation therapy (43% +/- 18%), but both were significantly better than maintenance therapy (19% +/- 17%), P = .047 and .043, respectively. The mortality rate for maintenance therapy was 0%, consolidation therapy, 21%; and alloBMT, 36%. Consolidation therapy caused an especially high mortality rate in the patients greater than or equal to 60 years old (8 of 14 or 57%). The toxicity of combined high-dose cytarabine and amsacrine is unacceptable, especially in older patients, and alternative approaches to consolidation therapy such as high-dose cytarabine alone need to be tested. In AML, a single course of consolidation therapy or alloBMT after initial CR produces better results than lengthy maintenance therapy. Although EFS and survival of alloBMT and consolidation therapy do not differ significantly, a larger number of patients need to be studied before concluding that they are equivalent.

In a prospective randomized study, five European transplant centers compared recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF; mammalian glycosylated) with placebo. rhGM-CSF was administered in a dose of 8 micrograms glycoprotein (5.5 micrograms protein)/kg/d, as a continuous intravenous (IV) infusion for 14 days, starting 3 hours after bone marrow infusion. Fifty-seven patients entered and completed the study. Median age of the recipients was 34 years (range, 17 to 51 y). All donors were HLA-identical, MLC-nonreactive siblings. Marrow grafts were depleted of T lymphocytes either by counterflow centrifugation (n = 42) or by immunological methods (n = 15). Twenty-nine patients received rhGM-CSF and 28 patients placebo. The leukocyte count and the absolute neutrophil count were significantly higher in the rhGM-CSF-treated group from day +9 to day +14 after bone marrow transplantation (BMT). This was also true for the monocyte count from day +12 to day +21. Early neutrophil (greater than 0.1 and greater than 0.3 x 10(9)/L) and early leukocyte (greater than 0.3 and greater than 0.5 x 10(9)/L) recovery was significantly faster for the patients given GM-CSF. The incidences of graft-versus-host disease (GVHD) and transplant-related mortality were not different in both groups. However, the number of bronchopneumonias was significantly lower in the rhGM-CSF-treated group (P = .03). Long-term follow-up showed a trend to better overall disease-free survival at 2 years and a trend to a lower relapse risk in patients treated with rhGM-CSF. This study shows that rhGM-CSF significantly increases neutrophil and monocyte counts during periods of 6 to 10 days in the second and third week after BMT. This shortened period until myeloid cell recovery after transplantation resulted in a decreased number of pneumonias, without an increase in incidence of GVHD or relapse.

A trial was initiated to determine the feasibility and efficacy of a three-phase treatment including: (1) induction chemotherapy (IC); (2) high-dose melphalan with total body irradiation supported by unpurged autologous bone marrow transplantation (ABMT); and (3) interferon (IFN) alpha maintenance treatment, in previously untreated aggressive myeloma. Thirty-five consecutive patients, ages under 65 years, were enrolled. Initial induction therapy was randomized between the VAD regimen (vincristine, doxorubicin, dexamethasone) or the VMCP regimen (vincristine, melphalan, cyclophosphamide, prednisone) that were found to give similar results as IC. Thirty-one of 35 (89%) patients, with good performance status and normal renal function after IC, received ABMT. IFN alpha was started soon after ABMT and was well tolerated. Fifteen of 35 (43%) patients achieved complete response (CR) and 14 of 35 (40%) achieved partial response (PR). Low pretreatment beta 2 microglobulin was the only predictive factor for accomplishing CR. The duration of response was significantly affected by the magnitude of response. The 33-month, post-ABMT probability of progression-free survival was 85% for patients in CR versus 24% for patients in PR. The 42-month, post-diagnosis probability of survival was 81%. This overall strategy may represent an advance in the management of multiple myeloma. Furthermore, the high rate and long duration of CR that we observed in patients with low beta 2 microglobulin suggest that such patients may preferentially benefit from this strategy.

Replacement therapy for hemophilia B (factor IX deficiency) using prothrombin complex concentrate (PCC) has been associated with serious complications of thromboembolic events and transmission of viral infections. Monoclonal antibody-purified factor IX (Mononine) provides a highly purified factor IX concentrate, while eliminating other vitamin K-dependent factors (II, VII, and X). Mononine was evaluated for in vivo recovery, half-life, and for its safety and efficacy in 10 patients with hemophilia B. The in vivo recovery of factor IX with Mononine was a 0.67 +/- 0.14 U/dL (mean +/- SD) increase per 1U/kg of infused factor IX, and the biologic half-life (t1/2), determined using the terminal phase of elimination, was 22.6 +/- 8.1 hours. Comparison of in vivo recovery of other vitamin K-dependent factors following a single infusion of either Mononine or PCC showed that, whereas Mononine infusion caused no changes in other vitamin K-dependent factors or in prothrombin activation fragment (F1+2), PCC infusion was associated with significant increases of factors II (2.7 U/dL per 1 U/dL of IX increase) and X (2.2 U/dL for 1 U/dL for 1 U/dL of IX). Patients who used Mononine as their sole therapeutic material during the 12-month period showed an excellent response in hemostasis for their bleeding episodes. Their experience with long-term use of Mononine was at least equivalent to their previous experience with PCC in the frequency and amount of factor usage. No patients developed antibody against mouse IgG or an increase in IX inhibitor during the 12-month period. These results indicate that monoclonal antibody-purified factor IX concentrate provides hemostatically effective factor IX replacement while avoiding extraneous thrombogenic substances.