Results from a large multinational clinical trial (guardian™3) using prophylactic treatment with turoctocog alfa in paediatric patients with severe haemophilia A: safety, efficacy and pharmacokinetics

Recombinant factor VIII (rFVIII) products provide a safe and efficacious replacement therapy for prophylaxis and treatment of bleeding episodes in patients with severe haemophilia A. This multinational, open-label, non-controlled trial investigated the safety, efficacy and pharmacokinetics (PK) of turoctocog alfa, a new rFVIII product, in a paediatric population. The primary objective was to evaluate safety. A total of 31 younger children (0-5 years) and 32 older children (6-11 years), with ≥ 50 exposure days to any factor VIII (FVIII) product and no history of inhibitors, received prophylaxis with turoctocog alfa (25-50 IU kg(-1) every second day or 25-60 IU kg(-1) three times weekly). PK assessments of turoctocog alfa and the patients' previous FVIII product were performed in 28 patients. Mean exposure to turoctocog alfa was 60 exposure days per patient. This corresponds to approximately 4.5 months in the trial. None of the patients developed inhibitors (≥ 0.6 BU) and no safety concerns were raised. A total of 120 bleeding episodes (95%) were controlled with 1-2 infusions of turoctocog alfa. Based on patient reports, the success rate (defined as 'excellent' or 'good' haemostatic response) for treatment of bleeding episodes was 92%. Overall, the median annualized bleeding rate was 3.0 (interquartile range: 8.5) bleeds patient(-1) year(-1) . PK parameters were comparable between the two age groups. In conclusion, the present large global clinical trial showed that turoctocog alfa was safe, effective in treatment of bleeding episodes and had a prophylactic effect in paediatric patients.

Results from a large multinational clinical trial (guardian™1) using prophylactic treatment with turoctocog alfa in adolescent and adult patients with severe haemophilia A: safety and efficacy

Recombinant factor VIII (rFVIII) products provide a safe and efficacious replacement therapy for prophylaxis and treatment of bleeding episodes in patients with severe haemophilia A. This multinational, open-label, non-controlled trial investigated the safety and efficacy of turoctocog alfa, a new rFVIII product. The primary objective was to evaluate safety. A total of 150 patients (24 adolescents and 126 adults) with severe haemophilia A (FVIII activity ≤ 1%), with at least 150 exposure days (EDs) to any FVIII product and no history of inhibitors were enrolled, and 146 patients (97%) completed the trial. All patients received prophylaxis with turoctocog alfa for approximately 6 months and had a mean of 85 EDs during the trial. None of the patients developed FVIII inhibitors, there were no indications of early FVIII inhibitor development and no safety concerns were identified. A total of 225 adverse events were reported in 100 (67%) patients, with the most common being events associated with dosing procedures, headaches, and nasopharyngitis. A total of 499 bleeding episodes were reported during the trial, the majority (89%) were controlled with 1-2 infusions of turoctocog alfa. Based on patient reports, the success rate (defined as 'excellent' or 'good' haemostatic response) for treatment of bleeding episodes was 81%. The overall median annualized bleeding rate was 3.7 (interquartile range: 8.7) bleeds/patient/year. In conclusion, turoctocog alfa provides a new, safe and effective alternative for prophylaxis and treatment of bleeding episodes in patients with haemophilia A.

Treatment of acquired haemophilia with recombinant activated FVII: a critical appraisal

Acquired haemophilia is a rare bleeding disorder usually caused by the spontaneous formation of inhibitory antibodies to coagulation FVIII. The disease occurs most commonly in the elderly, and although acquired haemophilia may be associated with a variety of underlying conditions, up to 50% of reported cases are idiopathic. Treatment options have traditionally involved human FVIII or FIX replacement therapy (if the inhibitor titre allows), porcine FVIII or the use of activated pro-thrombin complex concentrates. Recombinant activated coagulation FVII (rFVIIa) was available on an emergency and compassionate use basis from 1988 to 1999 at sites in Europe and North America. It has been registered in Europe for use in treating acquired haemophilia since 1996 and has recently been licensed for this indication in the United States. By directly activating FX on the surface of activated platelets at the site of injury (thereby bypassing FVIII and FIX), rFVIIa can circumvent the actions of inhibitory antibodies present in acquired haemophilia patients. This paper provides an overview of experiences with rFVIIa for the treatment of acquired haemophilia from the NovoSeven compassionate and emergency use programmes (1989-1999), the Hemophilia and Thrombosis Research Society Registry, and independent published reports from January 1999 to September 2005. rFVIIa has been reported to provide safe and effective haemostasis as a first line therapy in patients of all ages for a variety of surgical and non-surgical bleeding situations.

Human recombinant DNA-derived antihaemophilic factor (factor VIII) in the treatment of haemophilia A: conclusions of a 5-year study of home therapy. The KOGENATE Study Group

Fifty-eight previously treated haemophilic subjects were treated exclusively with the recombinant FVIII (rFVIII-KOGENATE) produced by Bayer Corporation (Berkeley, CA) in an international multicentre prospective study of more than 5 years duration. Fifty-four of the 58 had severe haemophilia (< 2% FVIII) and four had moderate haemophilia (2-5% FVIII); 23/58 (40%) were seropositive for HIV, while 35/58 (60%) were HIV seronegative. Patients were monitored for safety and efficacy over a median period of 4.7 years (range 0.9-5.9 years) and received 17 922 infusions totalling 25.7 million units of rFVIII. Of 7107 bleeding episodes reported in home diaries, 5831 (82%) required only one treatment with rVIII. Twenty-five invasive surgical procedures in 17 patients, including eight joint replacements, were successfully accomplished and 13 serious bleeding episodes in eight patients were successfully treated. FVIII recovery performed on 885 occasions using 39 different lots of rFVIII showed mean incremental recovery of 2.48% IU-1 kg-1 (+/- 0.64). Adverse events were associated with 42 infusions (0.2%); none caused discontinuation of therapy. Immunological parameters remained stable in HIV-seronegative subjects treated with rFVIII; a small decrease in CD4 counts was noted in HIV-seropositive individuals (mean - 37.2 cells mm-3 yr-1). No de novo formation of inhibitors to FVIII was noted; and no clinical allergic reactions occurred to murine or hamster proteins. These conclusions from the longest monitored safety study ever performed for a haemophilia treatment product (with more than 5 years of observation) confirm previous interim study reports that rFVIII is well tolerated over the long-term, has biological activity comparable to that of plasma-derived FVIII, and is safe and efficacious for the treatment of haemophilia A.

Breast health at midlife: guidelines for screening and patient evaluation

Breast cancer is the leading cause of death of American women aged 40 to 55. The fear that midlife women have of developing breast cancer must be considered as physicians discuss breast health with their patients. Identification of risk factors is important, although 70% of women diagnosed with breast cancer have no known risk factors. Screening mammograms can detect early lesions, but controversy exists over whether they reduce mortality in women younger than ago 50. The American Cancer Society and the National Cancer Institute recently changed their screening mammography recommendations for women aged 40 to 49. A breast self-exam can be performed using the circular or wedge techniques. If a mass is found, physicians can help alleviate a patient's anxiety by providing a diagnosis as quickly as possible.

Long term evaluation of septic arthritis in hemophilic patients

Before 1983, septic arthritis was rare in patients with hemophilia. With the advent of human immunodeficiency virus infection in the hemophilia population, many centers noted an increasing incidence of patients with septic arthritis. Fifteen septic joints in 10 patients with severe hemophilia were documented. Eight patients were human immunodeficiency virus positive, 1 was human immunodeficiency virus negative, and 1 was not tested. The diagnosis was delayed in 5 patients because the symptoms are similar to an acute hemarthrosis. An elevated temperature was common. The white blood cell count was elevated in only 1/3 of the infections, being modified by human immunodeficiency virus infection. Associated risk factors included infected angioaccess catheters (2), pneumonia (2), and generalized sepsis (1). All but 1 joint responded to appropriate antibiotics and either repeated aspiration or arthrotomy. However, 6 patients died of acquired immunodeficiency syndrome from 2 to 109 months after infection. Three patients are alive 29, 86, and 96 months, respectively, after infection.

Spurious fibrinogen levels secondary to pyroglobulinemia in Waldenström's macroglobulinemia

We report two cases of pyroglobulinemia detected in the course of routine determination of fibrinogen levels measured by the heat-precipitation method and that led to the diagnosis of Waldenström's macroglobulinemia. The incidence of pyroglobulinemia is briefly discussed, and the potential significance of this laboratory artifact is emphasized.

Internalization of human immunodeficiency virus type I and other retroviruses by megakaryocytes and platelets

Direct infection of megakaryocytes and platelets by human immunodeficiency virus type I (HIV-I) or other retroviruses has not been demonstrated. To determine whether this could occur, murine bone marrow was co-cultivated with the amphotropic retrovirus-producing cell line PA317-N2, and freshly isolated normal human bone marrow and platelets were co-cultivated with HIV-infected H9 cells. In each case, ultrastructural analyses showed viruses within megakaryocytes and platelets. In murine specimens, the uptake of retrovirus was avid at all stages of differentiation. In human specimens, viral uptake was less frequent. These results suggest that direct infection of megakaryocytes could play a role in the pathophysiology of HIV-associated disease. In addition, these observations suggest that cells of the megakaryocyte lineage could serve as target cells in gene transfer experiments using retroviral-based vectors.

Growth- and tumor-promoting effects of deregulated BCL2 in human B-lymphoblastoid cells

Human follicular B-cell lymphomas possess a t(14;18) that translocates a putative protooncogene, BCL2, into the immunoglobulin heavy chain locus. The normal BCL2 gene is quiescent in resting B cells, expressed in proliferating, but down-regulated in differentiated B cells. Inappropriately high levels of BCL2-immunoglobulin chimeric RNA are present in t(14;18) lymphomas for their mature B-cell stage. We examined the biologic effects of BCL2 deregulation in human B cells by introducing BCL2 into human B-lymphoblastoid cell lines (LCLs) with retroviral gene transfer. Although deregulated BCL2 expression as a single agent was not sufficient to confer tumorigenicity to LCLs, it consistently produced a 3- to 4-fold increment in LCL clonogenicity in soft agar. In addition, BCL2 deregulation complements the transforming effects of the MYC oncogene in LCLs. BCL2 augmented the clonogenicity of LCLs bearing exogenous MYC and increased the frequency and shortened the latency of tumor induction in immunodeficient mice. These results demonstrate a role for BCL2 as a protooncogene that affects B-cell growth and enhances B-cell neoplasia.

Monoclonal antibodies to the human CSF-1 receptor (c-fms proto-oncogene product) detect epitopes on normal mononuclear phagocytes and on human myeloid leukemic blast cells

The first monoclonal antibodies (MoAbs) to epitopes in the extracellular domain of the human c-fms proto-oncogene product (receptor for the macrophage colony stimulating factor, CSF-1) were used with flow cytometric techniques to study receptor expression on normal human peripheral blood monocytes, bone marrow cells, and leukemic blasts. On normal cells CSF-1 receptors were restricted in their expression to cells of the mononuclear phagocyte lineage. CSF-1 receptors were detected on leukemic blasts from 15 (30%) of 50 children with acute myeloid leukemia, compared with four (15%) of 26 adults. By contrast, detectable CSF-1 receptors were uniformly absent on blasts from 19 children with acute lymphoblastic leukemia. CSF-1 receptors on normal monocytes and myeloid leukemia cells could be induced to downmodulate by incubation with either human recombinant CSF-1 or phorbol esters, confirming that the receptors had functional ligand-binding sites and responded to transmodulation by inducers of protein kinase C. The numbers of receptors per cell and the percentage of positive cases were highest for leukemic blasts with cytochemical and morphological features of monocytes. However, CSF-1 receptors were also detected on a subset of leukemic blast cells with features of granulocytic differentiation (FAB subtypes M1 through M3). Southern blotting analyses of DNA from 47 cases of acute myeloid leukemia demonstrated no rearrangements within the 32 kb of genomic sequences that contain CSF-1 receptor coding exons or in the 50 kb upstream of the first coding exon. Analysis of the upstream region of the c-fms locus revealed that sequences representing the terminal 112 untranslated nucleotides of c-fms mRNA map 26 kb 5' to the first coding exon, suggesting that at least one c-fms promoter is separated from the receptor coding sequences by a very long intron. Whereas expression of the CSF-1 receptor in myeloid leukemic blasts is not restricted to cells with monocytic characteristics, the apparently aberrant pattern of receptor synthesis in a subset of cases with granulocytic features appears not to be due to chromosomal rearrangements within 50 kb upstream of sequences encoding the receptor.

Transformation and plasmacytoid differentiation of EBV-infected human B lymphoblasts by ras oncogenes

The biological effects of ras oncogene activation in B cells were studied by using amphotropic retroviral vectors to introduce H- or N-ras oncogenes into human B lymphoblasts immortalized by Epstein-Barr virus. Expression of both H- and N-ras oncogenes led to malignant transformation of these cells, as shown by clonogenicity in semisolid media and tumorigenicity in immunodeficient mice. In addition, terminal differentiation into plasma cells was detectable as specific changes in morphology, immunoglobulin secretion, and cell surface antigen expression. This combined effect, promoting growth and differentiation in human lymphoblasts, represents a novel biological action of ras oncogenes and has implications for the pathogenesis of terminally differentiated B-lymphoid malignancies such as multiple myeloma.

Diversity in inhibitory effects of IFN-gamma and IFN-alpha A on the induced DNA synthesis of a hairy cell leukemia B lymphocyte clone reflects the nature of the activating ligand

A hairy cell leukemia population was used as a clonal model for studying the direct immunomodulatory effects of recombinant interferon-alpha A (rIFN-alpha A) and rIFN-gamma on human B-cell proliferation. The leukemic cell population KON was notably quiescent when incubated in medium alone but was induced to significant in vitro DNA synthesis when cultured with any of four activators of human B cells: anti-IgM antibody, Staphylococcus aureus cells (SAC), phorbol myristate acetate (PMA), or B-cell growth factor (BCGF). While both rIFN-gamma and rIFN-alpha A exhibited suppressive effects on these responses, their inhibitory patterns were distinct and reciprocal. Thus, rIFN-gamma exclusively suppressed anti-IgM-and SAC-induced leukemic DNA synthesis, and rIFN-alpha A significantly suppressed only PMA- and BCGF-induced DNA synthesis. The effects of the rIFN preparations were ablated in the presence of IFN type-specific monoclonal antibodies. Kinetic analyses and pulsing studies revealed that inhibition was most notable when cells were exposed concomitantly to IFN and the activating ligand. That the diverse effects of IFN-gamma and IFN-alpha A are manifested on a single B-cell clone was confirmed by Southern blot analysis of restriction enzyme-digested KON cell DNA with a JH-specific probe. These studies suggest that the therapeutic potential of the two types of IFN may be influenced by the nature of the extracellular ligands in the leukemic mileau that promote leukemic clonal expansion.

Human leukemic B cell activation: functional consequence of membrane IgM interaction with anti-IgM ligand is an alterable cell characteristic

A functional study of several human malignant B cell populations has indicated that occasional leukemic clones are extraordinarily sensitive to signal transduction through membrane IgM. One isolated hairy cell leukemia (HCL) with low background DNA synthesis was stimulated to significant levels of DNA synthesis when cultured with high (100 micrograms/mL) concentrations of soluble anti-IgM ligands. In contrast to the activation of normal peripheral blood polyclonal B cells, this DNA synthesis was completely independent of accessory T cell factors. Although the HCL clone could also be induced to enter S phase by incubation in media supplemented with only activated T cell supernatant, culture of the clone with activated T cell supernatant plus anti-IgM Ab resulted in DNA synthesis that was significantly less than that induced by either activator alone. Factor(s) in T cell supernatant appear to modulate the leukemic clone so that the binding of ligand to membrane IgM is perceived as an inhibitory rather than a stimulatory signal for DNA synthesis. In terms of Ig Fc independence and low ligand dose requirements, anti-IgM-mediated inhibitory signal transduction in the T cell supernatant-activated HCL clone was found to mimic anti-IgM mediated suppression of the spontaneous DNA synthesis of an alternative HCL clone. The functional results suggest that the type of signal transduced anti-Ig ligands may reflect differences in the activation state of receptive leukemic B cells.

Trisomy 22--a new abnormality found in acute leukemia characterized by eosinophilia and monocytoid blasts expressing immature differentiation antigens

Bone marrow cells from three patients with acute myeloid leukemia, with marrow eosinophilia and monocytoid blasts, showed a new nonrandom chromosomal abnormality, trisomy 22. In two patients the classification of leukemia was M4 and in the third patient M2 (FAB classification). Pretreatment bone marrows in these patients revealed 31%, 30%, and 4% eosinophils, respectively. Blast cells isolated from peripheral blood were Ia-positive and expressed immature monocyte lineage antigens (U26, U28, U48) in 26%-92% of cells. All three patients had a population of bone marrow cells characterized by an extra chromosome #22. One patient also had inversion of chromosome #16. Trisomy 22, bone marrow eosinophilia, and monocytoid blasts displaying early monocyte differentiation antigens may represent a new subgroup of patients with acute myeloid leukemia.

Acute nonlymphocytic leukemia following gastric adenocarcinoma treated by surgery alone. Evidence for etiologic heterogeneity of "secondary" leukemias

The case of a 36-year-old Hispanic man who developed acute nonlymphocytic leukemia 18 months following gastric adenocarcinoma treated by surgery alone is presented. Cytogenetic analysis of the leukemic cells revealed numerical and structural chromosomal rearrangements including chromosomes 5 and 7 and immunologic characterization of the blasts revealed terminal deoxynucleotidyltransferase positivity with monocytoid features. This report suggests that not all cases of acute nonlymphocytic leukemia following chemotherapy and/or radiotherapy, which characteristically display similar cytogenetic and immunologic features, should be exclusively ascribed to the leukemogenic properties of anticancer treatment.

Definition of a possible genetic basis for susceptibility to acute myelogenous leukemia associated with the presence of a polymorphic Ia epitope

The polymorphic Ia epitope recognized by monoclonal antibody 109d6 is detectable on the leukemic cells of a significantly increased number of individuals with acute myelogenous leukemia, compared with its frequency in normal healthy control individuals. In control individuals, the presence of the 109d6 epitope is closely correlated with but not identical to the DRw53 allo-specificity. However, the frequency of particular conventional Ia allodeterminants, including DRw53, is not significantly elevated in the leukemia group. Considerable evidence supports the conclusion that the high frequency of the 109d6 epitope reflects an inherited basis for susceptibility to the development of acute myelogenous leukemia and not a differentiation event occurring in the leukemic lineage. The 109d6 determinant is expressed by leukemic myeloblasts as well as by homologous normal B cells and monocytes obtained from the same individuals during remission of the leukemia. Furthermore, in healthy family members the 109d6 epitope is encoded by Ia haplotypes that are shared with the patient. Of special interest, certain of these haplotypes have combinations of the 109d6 epitope and Ia specificities not commonly seen in normal individuals; here, also, healthy family members share these haplotypes.

Definition of AML susceptibility and classification using monoclonal antibodies

Of 112 patients with acute leukemia 13 exhibited terminal deoxyribonucleotidyl transferase activity (TdT) with a cell phenotype characterized by the presence of early or mature monocyte differentiation antigens detected by monoclonal antibodies and elevated serum lysozyme. These cells were either unclassifiable by cytochemical analysis or fell into the M2 or M5 categories by the French-American-British classification. These leukemias appear to form a distinct nosologic entity representing a malignant transformation among early cells in the monocyte lineage. Among 60 patients with acute myelogenous leukemia 87% expressed the polymorphic Ia antigen detected by monoclonal antibody 109d6 compared to an incidence of 40.5% in the control population, relative risk 9.2. Evidence was obtained that this antigen was present in healthy family members and remission B-cells and monocytes of patients, and that its presence was associated with a genetically defined susceptibility state for the development of acute myelogenous leukemia.

TdT-positive acute leukemia with monocytoid characteristics: clinical, cytochemical, cytogenetic, and immunologic findings

Thirteen patients with acute leukemias that were difficult to classify by the use of cytochemical staining and terminal deoxyribonucleotidyl transferase (TdT) activity are reported. The phenotype of the leukemic cells was characterized by the presence of mature or early monocyte lineage antigens and intense Ia antigen expression detected by monoclonal antibodies, terminal deoxytransferase activity, and cytochemical features, including both Sudan black B and periodic acid-Schiff activity. The mean age of this group of patients was 60 years. Five patients had leukemia occurring after chemotherapy or radiotherapy of a prior malignant disease, and two patients had a refractory anemia prior to development of acute leukemia. These patients had a low response rate to chemotherapy. This series of leukemia appears to form a distinct nosologic entity, representing a leukemic transformation among early cells of the monocyte lineage, resulting in a predominant neoplastic cell that is less mature than either the French-American-British M4 acute myelomonocytic leukemia or M5 acute monoblastic leukemia. The presence of terminal deoxytransferase activity was interpreted as indicating the primitive state of the cells in the differentiation sequence, rather than as implying any significance with respect to lineage.

Evidence for the separate molecular expression of four distinct polymorphic Ia epitopes on cells of DR4 homozygous individuals

The monoclonal antibodies 109d6 and IVD12 reacted with separate polymorphic Ia epitopes in immunofluorescent studies. Using a panel of lymphoblastoid B cell lines, antibody 109d6 reacted with all HLA-DR4 or DR7 positive lines in a pattern resembling the MT3 specificity recognized by human alloantisera. The antibody IVD12 reacted with all HLA-DR4 and two of three DR5 positive B cell lines suggesting that it recognized a specificity similar to MB3. The intensity of fluorescence was greater on DR5(+) cell lines than on DR4(+) cell lines relative to the amount of a nonpolymorphic Ia determinant. Among 45 unrelated control individuals reactivity with antibody 109d6 was correlated most closely with (r = 0.724) but not identical in occurrence to the MT3 specificity. Cocapping experiments demonstrated that the 109d6 epitope and the IVD12 epitope were present on independently redistributed cell surface molecules of DR4 homozygous lymphoblastoid cell lines. Furthermore, the DR4 alloantigens detected by an absorbed polyclonal human alloserum were similarly identified on molecules that were independent from those bearing either the 109d6 epitope or the IVD12 epitope. Taken together, these data indicate the existence of at least four distinct, serologically defined Ia molecular species.

The dental hygienist--a member of the team?

The importance and role of computed tomography (CT) are discussed on the basis of 36 cases of vertebral osteomyelitis. The bone images themselves, the detection of lumbar disk hypodensity, and the exploration of soft paraspinal regions in the search for an abscess are factors that contribute to the superiority of this method in difficult cases. In cases where the diagnosis is already known, CT offers an excellent method to assess the extent of the lesions. Its accuracy, coupled with its rapidity and noninvasive nature, affects the role of conventional tomography, a method that is incomplete and involves higher radiation doses. CT offers an excellent method for follow-up after treatment of vertebral osteomyelitis.