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1.
J Thromb Haemost ; 16(10): 1984-1993, 2018 10.
Article in English | MEDLINE | ID: mdl-30151972

ABSTRACT

Essentials Marzeptacog alfa (activated) [MarzAA] is a novel variant of activated human factor VII. A phase 1 dose escalation trial of MarzAA was conducted in subjects with severe hemophilia. MarzAA was safe and tolerated at intravenous doses up to 30 µg kg-1 Data observed support further trials for hemophilia patients with inhibitors to factors VIII/IX. SUMMARY: Background Marzeptacog alfa (activated) (MarzAA), a new recombinant activated human factor VII (rFVIIa) variant with four amino acid substitutions, was developed to provide increased procoagulant activity and a longer duration of action in people with hemophilia. Objectives To investigate the safety, tolerability, immunogenicity, pharmacokinetics (PK) and pharmacodynamics (PD) of single ascending intravenous bolus doses of MarzAA in non-bleeding patients with congenital hemophilia A or B with or without inhibitors. Methods This international, phase 1, open-label study (NCT01439971) enrolled males aged 18-64 years with severe hemophilia A or B, with or without FVIII or FIX inhibitors. Subjects were assigned to single-dose MarzAA cohorts (0.5, 4.5, 9, 18 or 30 µg kg-1 ). Blood sampling was performed predose and postdose, and subjects were monitored for 60 days postdose. Safety endpoints included adverse events, vital sign changes, electrocardiograms, laboratory abnormalities, and immunogenicity; secondary endpoints included evaluation of PK and PD. Results Overall, in 25 patients, MarzAA was well tolerated at all dose levels tested, and was not associated with dose-limiting toxicity. No treatment-emergent severe or serious adverse events occurred. MarzAA showed linear dose-response PK across the 4.5-30 µg kg-1 dose range, with a terminal half-life of ⁓ 3.5 h. Dose-dependent shortening of the activated partial thromboplastin time and prothrombin time, and evidence of an increase in peak thrombin as determined with a thrombin generation assay, were observed at all doses. Conclusions MarzAA was tolerated at doses up to 30 µg kg-1 . The safety profile and pharmacological effects observed support further clinical trials for the treatment of hemophilic patients with inhibitors.


Subject(s)
Coagulants/administration & dosage , Factor VIIa/administration & dosage , Hemophilia A/drug therapy , Hemophilia B/drug therapy , Administration, Intravenous , Adolescent , Adult , Coagulants/adverse effects , Coagulants/pharmacokinetics , Europe , Factor VIIa/adverse effects , Factor VIIa/pharmacokinetics , Hemophilia A/blood , Hemophilia A/diagnosis , Hemophilia B/blood , Hemophilia B/diagnosis , Humans , Male , Middle Aged , Recombinant Proteins/administration & dosage , Recombinant Proteins/adverse effects , Recombinant Proteins/pharmacokinetics , Severity of Illness Index , South Africa , Time Factors , Treatment Outcome , United States , Young Adult
2.
J Thromb Haemost ; 16(9): 1722-1731, 2018 09.
Article in English | MEDLINE | ID: mdl-29908043

ABSTRACT

Essentials Tissue factor pathway inhibitor (TFPI) is an antagonist of FXa and the TF-FVIIa complex. PF-06741086 is an IgG1 monoclonal antibody that targets the Kunitz-2 domain of TFPI. Single doses of PF-06741086 were evaluated in a phase 1 study in healthy volunteers. Data from this study support further investigation of PF-06741086 in individuals with hemophilia. SUMMARY: Background Tissue factor pathway inhibitor (TFPI) is a protease inhibitor of the tissue factor-activated factor VII complex and activated FX. PF-06741086 is a mAb that targets TFPI to increase clotting activity. Objectives This study was a randomized, double-blind, sponsor-open, placebo-controlled, single intravenous or subcutaneous dose escalation study to evaluate the safety, tolerability, pharmacokinetics and pharmacodynamics of PF-06741086. Patients/Methods Volunteers who provided written informed consent were assigned to cohorts with escalating dose levels. Safety endpoints included treatment-emergent adverse events (TEAEs), infusion/injection site reactions, vital signs, electrocardiogram, and coagulation and hematology laboratory parameters. Pharmacokinetic (PK) and pharmacodynamic (PD) endpoints included exposures of PF-06741086 in plasma and measures of PF-06741086 pharmacology, respectively. Results Forty-one male volunteers were recruited overall. Thirty-two were dosed with PF-06741086 from 30 mg subcutaneously to 440 mg intravenously. All doses were safe and well tolerated. TEAEs were mild or moderate in severity, laboratory abnormalities were transient, there were no serious adverse events, there were no infusion/injection site reactions, and no dose escalation stopping criteria were met. Plasma exposures of PF-06741086 increased greater than proportionally with dose under the same dosing route. Coagulation pharmacology was demonstrated via total TFPI, dilute prothrombin time, D-dimer, prothrombin fragment 1 + 2 and thrombin generation assay parameters. Conclusions Single doses of PF-06741086 at multiple dose levels were safe and well tolerated in a healthy adult male population. The safety, PK and PD data from this study support progression to a multiple-dose study in hemophilic patients.


Subject(s)
Antibodies, Monoclonal, Humanized , Hemostatics/administration & dosage , Lipoproteins/antagonists & inhibitors , Adolescent , Adult , Antibodies, Anti-Idiotypic/blood , Antibodies, Monoclonal, Humanized/adverse effects , Antibodies, Monoclonal, Humanized/pharmacokinetics , Antibodies, Monoclonal, Humanized/pharmacology , Antibodies, Neutralizing/blood , Dose-Response Relationship, Drug , Double-Blind Method , Fatigue/chemically induced , Half-Life , Hemodynamics/drug effects , Hemostatics/adverse effects , Hemostatics/blood , Hemostatics/pharmacology , Humans , Injections, Intravenous , Injections, Subcutaneous , Lipoproteins/blood , Lipoproteins/immunology , Male , Middle Aged , Pain/chemically induced , Young Adult
3.
J Thromb Haemost ; 15(5): 931-937, 2017 05.
Article in English | MEDLINE | ID: mdl-28294526

ABSTRACT

Essentials FXaI16L is a recombinant zymogen-like variant of activated coagulation factor X (FXa). A phase 1 dose escalation clinical trial of FXaI16L was conducted in healthy adults. FXaI16L was safe and tolerated at doses up to 5 µg/kg; no dose-limiting toxicity was observed. Data support further development of FXaI16L for patients with acute hemorrhagic conditions. SUMMARY: Background FXaI16L (PF-05230907) is a zymogen-like variant of activated factor X (FXa). It shows enhanced resistance to inactivation by endogenous inhibitors as compared with wild-type FXa, and restores hemostatic activity in non-clinical models of various bleeding conditions. Objectives To evaluate the safety, pharmacokinetics and pharmacodynamics of FXaI16L by performing a phase 1, first-in-human, dose-escalation clinical trial in healthy adult volunteers. Methods Participants were assigned to one of six ascending single-dose cohorts (0.1, 0.3, 1, 2, 3 or 5 µg kg-1 ), each planned to comprise six volunteers treated with FXaI16L and two treated with placebo. Assessments included safety monitoring, pharmacokinetic and pharmacodynamic (PD) analyses, and immunogenicity testing. Results The trial enrolled 49 male volunteers. Administration of a single intravenous bolus dose of FXaI16L was safe and tolerated at all dose levels tested, with no dose-limiting toxicity or serious adverse events. FXaI16L plasma levels appeared to increase dose-proportionally, with a half-life of ~ 4 min. Treatment-related PD changes were observed for activated partial thromboplastin time, thrombin generation assay, thrombin-antithrombin complexes, prothrombin fragment 1 + 2, and D-dimer. One volunteer had a weak and transient non-neutralizing antidrug antibody response, which did not cross-react with native FX or native FXa. Conclusions FXaI16L was safe and tolerated, and showed a pharmacologic effect in healthy adults when administered at doses up to 5 µg kg-1 . The safety profile, pharmacokinetics and pharmacodynamics observed in this clinical trial support the further development of FXaI16L for hemostatic treatment in individuals with acute hemorrhagic conditions.


Subject(s)
Blood Coagulation/drug effects , Coagulants/pharmacokinetics , Factor Xa/pharmacokinetics , Adolescent , Adult , Antibodies/blood , Antithrombin III , Area Under Curve , Biomarkers/blood , Coagulants/administration & dosage , Coagulants/adverse effects , Coagulants/immunology , Double-Blind Method , Factor Xa/administration & dosage , Factor Xa/adverse effects , Factor Xa/immunology , Fibrin Fibrinogen Degradation Products/metabolism , Half-Life , Healthy Volunteers , Humans , Injections, Intravenous , Male , Metabolic Clearance Rate , Partial Thromboplastin Time , Peptide Fragments/blood , Peptide Hydrolases/blood , Prothrombin , Prothrombin Time , Recombinant Proteins , Young Adult
4.
AAPS J ; 16(4): 658-73, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24764037

ABSTRACT

Immunogenicity is a significant concern for biologic drugs as it can affect both safety and efficacy. To date, the descriptions of product immunogenicity have varied not only due to different degrees of understanding of product immunogenicity at the time of licensing but also due to an evolving lexicon that has generated some confusion in the field. In recent years, there has been growing consensus regarding the data needed to assess product immunogenicity. Harmonization of the strategy for the elucidation of product immunogenicity by drug developers, as well as the use of defined common terminology, can benefit medical practitioners, health regulatory agencies, and ultimately the patients. Clearly, understanding the incidence, kinetics and magnitude of anti-drug antibody (ADA), its neutralizing ability, cross-reactivity with endogenous molecules or other marketed biologic drugs, and related clinical impact may enhance clinical management of patients treated with biologic drugs. To that end, the authors present terms and definitions for describing and analyzing clinical immunogenicity data and suggest approaches to data presentation, emphasizing associations of ADA development with pharmacokinetics, efficacy, and safety that are necessary to assess the clinical relevance of immunogenicity.


Subject(s)
Peptides/immunology , Peptides/therapeutic use , Proteins/immunology , Proteins/therapeutic use , Terminology as Topic , Antibody Formation/drug effects , Guidelines as Topic , Humans , Peptides/pharmacokinetics , Proteins/pharmacokinetics
5.
Haemophilia ; 16(5): 731-9, 2010 Sep 01.
Article in English | MEDLINE | ID: mdl-20412322

ABSTRACT

SUMMARY: Moroctocog alfa (AF-CC) (Xyntha, BDDrFVIII) is manufactured by a process designed to enhance the theoretical viral safety profile relative to ReFacto, its predecessor, and to provide alignment with clinical monitoring by the one-stage clotting assay. To evaluate the efficacy and safety of B-domain-deleted recombinant factor VIII (BDDrFVIII) was given as bolus injection (BI) or continuous infusion (CI) in haemophilia patients undergoing major surgery. BDDrFVIII was administered by BI or CI per investigator discretion peri-operatively for at least 6 days. Thirty patients enrolled and were treated with at least one dose of BDDrFVIII. Twenty-five patients were evaluable for efficacy. Outcomes were favourable against a background of multiple major surgical procedures. All haemostatic efficacy ratings were 'excellent' or 'good'. End-of-surgery haemostasis ratings, the primary efficacy endpoint, were excellent for 72% (18/25) and good for 28% (7/25) of patients. Haemostasis ratings following the initial postoperative period were excellent for 92% (23/25) and good for 8% (2/25) of patients. Intra-operative blood loss was rated as normal in all patients. Thirteen patients had postoperative blood loss; in 10, this was rated as normal. A low frequency of transfusion was reported in both the intra-operative and postoperative settings. Adverse events (AEs) were consistent with surgery; three were considered related to BDDrFVIII. One patient had a related AE of postoperative haemorrhage. A clinically silent low-titre inhibitor was detected in one patient, and one patient had a false-positive inhibitor titre. This study demonstrates that BDDrFVIII is safe and efficacious for surgical prophylaxis in haemophilia A patients undergoing major surgery.


Subject(s)
Blood Loss, Surgical/prevention & control , Factor VIII/therapeutic use , Hemophilia A/drug therapy , Hemostasis, Surgical/methods , Peptide Fragments/therapeutic use , Adult , Blood Coagulation Factor Inhibitors/blood , Factor VIII/pharmacokinetics , Humans , Infusion Pumps , Injections, Intra-Arterial , Male , Peptide Fragments/pharmacokinetics , Prospective Studies
6.
Haemophilia ; 15(4): 869-80, 2009 Jul.
Article in English | MEDLINE | ID: mdl-19473411

ABSTRACT

BDDrFVIII is a B-domain deleted recombinant factor VIII (rFVIII) product for haemophilia A. Manufacture uniquely includes purification chromatography by synthetic-affinity ligand rather than murine-based monoclonal antibody, as well as an albumin-free cell culture process. BDDrFVIII was studied in 204 patients, including 62 subjects <16 years old, in two studies. A double-blind, randomized, pharmacokinetic (PK) crossover study, utilizing a central laboratory assay (one-stage (OS)) for both drug potency assignment and plasma FVIII-activity measurements, demonstrated that BDDrFVIII was PK-equivalent to a full-length rFVIII. Favourable efficacy and safety were observed: during defined routine prophylaxis in a patient population significant for preexisting target joints, nearly half (45.7%) of patients had no bleeding, and a low-annualized bleed rate (ABR) was achieved (median 1.9); 92.5% of haemorrhages (n = 187) required < or =2 infusions. Three subjects (1.5%, across both studies) developed de novo inhibitors (low-titre, transient), and the primary safety endpoint, based on a prospective Bayesian analysis, demonstrated the absence of neoantigenicity for BDDrFVIII. The PK-equivalence, based on central testing to align test and reference articles, and the novel Bayesian analysis of inhibitor safety in these investigations reflect robust experimental designs with relevance to future studies. This extensive dataset demonstrates the safety and efficacy of BDDrFVIII for haemophilia A.


Subject(s)
Blood Coagulation Factor Inhibitors/pharmacokinetics , Factor VIII/pharmacokinetics , Hemophilia A/drug therapy , Peptide Fragments/pharmacokinetics , Adolescent , Adult , Bayes Theorem , Blood Coagulation Factor Inhibitors/genetics , Child , Factor VIII/genetics , Hemophilia A/genetics , Humans , Male , Middle Aged , Peptide Fragments/genetics , Treatment Outcome , Young Adult
7.
Haemophilia ; 13(5): 508-17, 2007 Sep.
Article in English | MEDLINE | ID: mdl-17880437

ABSTRACT

Strategies for the management of perioperative bleeding in patients with haemophilia and inhibitors have evolved rapidly as a result of the development of the bypassing agents Factor Eight Inhibitor Bypassing Activity, Anti-inhibitor Coagulant Complex (FEIBA) and activated recombinant factor VII (rFVIIa). However, there are currently no established guidelines for perioperative use of bypassing agents, and few controlled clinical studies have been carried out. Thus, case reports, such as those presented here, provide useful anecdotal evidence to guide the treatment of inhibitor patients. The purpose of this report was to describe experiences in the use of bypassing agents in a small cohort of patients with haemophilia A and inhibitors undergoing surgical procedures. Cases from five treatment centres were reviewed. Twenty-two procedures using FEIBA, rFVIIa or a combination of both agents were compiled from seven inhibitor patients (six with an alloantibody inhibitor and one with an acquired autoantibody inhibitor). Eleven procedures used FEIBA monotherapy, two employed rFVIIa monotherapy and nine were performed using combination therapy. Supplemental therapies were required to manage bleeding in some cases. Haemostatic control was achieved in all cases, and treatment regimens were generally well tolerated. One thrombotic adverse event was reported: evidence of disseminated intravascular coagulation (DIC) was found after rFVIIa use in one case, although the direct cause of DIC was unknown. The experiences in this case review demonstrate that both major and minor surgical procedures can be safely performed in patients with haemophilia and high-titre inhibitors under the cover of bypassing agents, with a high expectation of success.


Subject(s)
Blood Coagulation Factor Inhibitors/metabolism , Blood Coagulation Factors/administration & dosage , Blood Loss, Surgical/prevention & control , Factor VII/administration & dosage , Hemophilia A/complications , Adult , Blood Coagulation Factors/adverse effects , Child, Preschool , Drug Therapy, Combination , Factor VII/adverse effects , Factor VIIa , Female , Hemophilia A/immunology , Humans , Infant , Male , Recombinant Proteins/administration & dosage , Recombinant Proteins/adverse effects , Retrospective Studies , Treatment Outcome
8.
J Evol Biol ; 20(5): 1882-9, 2007 Sep.
Article in English | MEDLINE | ID: mdl-17714305

ABSTRACT

Understanding the evolution of microbial diversity is an important and current problem in evolutionary ecology. In this paper, we investigated the role of two established biochemical trade-offs in microbial diversification using a model that connects ecological and evolutionary processes with fundamental aspects of biochemistry. The trade-offs that we investigated are as follows:(1) a trade-off between the rate and affinity of substrate transport; and (2) a trade-off between the rate and yield of ATP production. Our model shows that these biochemical trade-offs can drive evolutionary diversification under the simplest possible ecological conditions: a homogeneous environment containing a single limiting resource. We argue that the results of a number of microbial selection experiments are consistent with the predictions of our model.


Subject(s)
Bacteria/metabolism , Biological Evolution , Fungi/metabolism , Models, Biological , Bacteria/classification , Bacteria/growth & development , Biodiversity , Fungi/classification , Fungi/growth & development
9.
Haemophilia ; 11(2): 84-91, 2005 Mar.
Article in English | MEDLINE | ID: mdl-15810908

ABSTRACT

BACKGROUND: Deletion of the B-domain of recombinant blood coagulation factor VIII (BDDrFVIII) increases the manufacturing yield of the product but does not impair in vitro or in vivo functionality. BDDrFVIII (ReFacto) has been developed with the additional benefit of being formulated without human albumin. OBJECTIVE: The primary objective of this three-way crossover-design study was to compare the pharmacokinetic (PK) parameters of two BDDrFVIII formulations (one reconstituted with 5 mL of sterile water, the other reconstituted with 4 mL sodium chloride 0.9% USP) with those of a plasma-derived, full-length FVIII preparation (Hemofil M) in patients with haemophilia A to determine bioequivalence. METHODS: A series of blood samples were collected over a period of 48 h after i.v. administration of each of the FVIII preparations. Plasma FVIII activity was determined using a validated chromogenic substrate assay. Plasma FVIII activity vs. time curves was characterized for a standard set of PK parameter estimates. Two parameter estimates, the maximum plasma concentration (Cmax) and the area under plasma concentration vs. time curves (AUCs), were used to evaluate bioequivalence. The two preparations were considered bioequivalent if the 90% confidence intervals for the ratio of geometric means for Cmax and AUCs fell within the bioequivalence window of 80% to 125%. RESULTS/CONCLUSION: Results show that each BDDrFVIII formulation is bioequivalent to Hemofil M and the two formulations of BDDrFVIII are bioequivalent to each other.


Subject(s)
Factor VIII/pharmacokinetics , Hemophilia A/drug therapy , Adolescent , Adult , Antibodies, Monoclonal , Area Under Curve , Cross-Over Studies , Factor VIII/adverse effects , Factor VIII/analysis , Hemophilia A/immunology , Hemophilia A/metabolism , Humans , Plasma , Recombinant Proteins/adverse effects , Recombinant Proteins/pharmacokinetics , Single-Blind Method , Therapeutic Equivalency
10.
J Thromb Haemost ; 2(4): 574-83, 2004 Apr.
Article in English | MEDLINE | ID: mdl-15102011

ABSTRACT

BACKGROUND: Development of recombinant factor VIII (rFVIII) replacement therapy represents a milestone in the treatment of hemophilia A. OBJECTIVE: The objective of this long-term, multicenter study was to assess the safety, efficacy and rate of inhibitor formation of rFVIII (Kogenate) in the treatment of hemophilia A in a group of previously untreated patients (PUPs). PATIENTS AND METHODS: Between January 1989 and October 1997, 102 evaluable patients (mean age 3.9 years) were treated with rFVIII as sole therapy for prophylaxis against bleeding or for hemorrhage. Patients with mild hemophilia were treated for > or =2 years, while those with moderate or severe hemophilia were treated for > or =5 years or 100 exposure days. RESULTS: All patients responded well to therapy, so that 82% of bleeding episodes required a single infusion for treatment. Only four mild drug-related adverse events were recorded during the study for an overall rate of 0.03% (4/13 464 infusions). No viral seroconversions were observed. The inhibitor incidence in PUPs with severe hemophilia was 29% (19/65). Overall, inhibitory antibodies developed in 21 patients (20.6%). Inhibitor titers were low (<10 Bethesda Units) in nine of the 21 patients despite continued episodic treatment with rFVIII and transient in eight patients receiving episodic treatment (seven low titer, one high titer). Eight high-titer inhibitor patients were treated with immune-tolerance induction therapy; five had successful outcomes. CONCLUSIONS: The observed incidence of inhibitor formation is similar to studies of PUPs receiving plasma-derived FVIII. These results demonstrate the safety and efficacy of rFVIII in long-term treatment of hemophilia A.


Subject(s)
Factor VIII/administration & dosage , Hemophilia A/drug therapy , Adolescent , Adult , Animals , Antibodies, Heterophile/blood , Antibody Formation , Child , Child, Preschool , Cricetinae , Factor VIII/adverse effects , Factor VIII/immunology , Hemophilia A/immunology , Hemorrhage/drug therapy , Hemorrhage/prevention & control , Humans , Immune Tolerance , Incidence , Infant , Infant, Newborn , Isoantibodies/blood , Male , Mice , Middle Aged
12.
Am J Alzheimers Dis Other Demen ; 16(4): 211-24, 2001.
Article in English | MEDLINE | ID: mdl-11501343

ABSTRACT

UNLABELLED: Three direct measures of dementia insight were administered to 20 participants in a longitudinal Alzheimer's disease (AD) rehabilitation research project and to subsets of these participants that completed one (N = 19), two (N = 12), and three (N = 6) years of program participation. The measures were: (1) responses to a discourse prompt question about AD (ADPQ); (2) endorsements of seven items on the Geriatric Depression Scale (GDS) about the effects of dementia (separate analyses were done for two of the seven items that related specifically to memory and thinking); and (3) a sentence-completion exercise. Responses to measures 1 and 2 and the subset of 2 were quantified, tracked over time, and subjected to correlational analyses with age, Mini-Mental State Exam (MMSE) score, and depression, as measured by total GDS score, and with each other. MAJOR FINDINGS: There were no decreases in insight from baseline to year 1, 2, or 3, as measured by free responses to the AD prompt question. There was a significant decline in insight from baseline to year one on the GDS measure, but no change from year 1 to year 2 and a return to baseline level at year 3. There was no correlation between insight and baseline age, between insight and MMSE score at any time point, between MMSE score and depression, as measured by total GDS score, or between MMSE score and depression score, except for the year 3 completers, where depression score was negatively correlated with MMSE score at year 3 only. GDS insight and ADPQ scores were not correlated. Several participants that showed no insight on the quantified measures did so on the sentence completions.


Subject(s)
Alzheimer Disease/psychology , Depressive Disorder, Major/diagnosis , Depressive Disorder, Major/etiology , Aged , Cognition Disorders/diagnosis , Follow-Up Studies , Geriatric Assessment , Humans , Neuropsychological Tests , Severity of Illness Index
13.
J Acquir Immune Defic Syndr ; 26(5): 466-72, 2001 Apr 15.
Article in English | MEDLINE | ID: mdl-11391167

ABSTRACT

Coinfection with hepatitis C virus (HCV) and HIV-1 is common in patients with hemophilia and in intravenous drug users. Little, however, is known about the relation between HIV-1 and HCV coinfection and the effects on HCV clearance and pathogenesis. We examined data from 207 HIV-1-infected and 126 HIV-1-uninfected patients with hemophilia enrolled in the multicenter Hemophilia Growth and Development Study. Participants were observed during prospective follow-up for approximately 7 years with annual measurements of alanine aminotransferase (ALT), CD4+ cells, and HCV and HIV-1 RNA levels. Clearance of HCV was more likely to occur in those uninfected with HIV-1 (14.3 versus 2.5%; odds ratio [OR] 4.79; 95% confidence interval [CI], 1.63-14.08, p =.005) and was more common with decreasing age (OR, 1.23; 95% CI, 1.04-1.47; p =.017). HCV RNA levels were higher throughout the 7 years of follow-up in those HIV-1-infected (p <.001). In the HIV-1-infected participants, baseline CD4+ cells were inversely related to HCV RNA with every 100-cell increase associated with a 0.19 log10 copy/ml decrease in HCV RNA (p =.002), and HIV-1 and HCV RNA levels were directly related (p =.008). Increasing HCV RNA levels were also associated with significantly higher ALT levels regardless of HIV-1 infection status. These results demonstrate that HIV-1/HCV co-infection is associated with a reduced likelihood of HCV clearance and that higher levels of HCV RNA are associated with increased hepatic inflammation.


Subject(s)
HIV Infections/virology , HIV-1/physiology , Hemophilia A/complications , Hemophilia A/virology , Hepacivirus/physiology , Hepatitis C/virology , Adolescent , Adult , Alanine Transaminase/blood , Anti-HIV Agents/therapeutic use , CD4 Lymphocyte Count , Child , Cohort Studies , HIV Infections/complications , HIV Infections/drug therapy , Hepatitis C/complications , Humans , RNA, Viral/blood , Viral Load
14.
Blood ; 97(5): 1211-8, 2001 Mar 01.
Article in English | MEDLINE | ID: mdl-11222362

ABSTRACT

The Dana-Farber Cancer Institute (DFCI) acute lymphoblastic leukemia (ALL) Consortium Protocol 91-01 was designed to improve the outcome of children with newly diagnosed ALL while minimizing toxicity. Compared with prior protocols, post-remission therapy was intensified by substituting dexamethasone for prednisone and prolonging the asparaginase intensification from 20 to 30 weeks. Between 1991 and 1995, 377 patients (age, 0-18 years) were enrolled; 137 patients were considered standard risk (SR), and 240 patients were high risk (HR). Following a 5.0-year median follow-up, the estimated 5-year event-free survival (EFS) +/- SE for all patients was 83% +/- 2%, which is superior to prior DFCI ALL Consortium protocols conducted between 1981 and 1991 (P =.03). There was no significant difference in 5-year EFS based upon risk group (87% +/- 3% for SR and 81% +/- 3% for HR, P =.24). Age at diagnosis was a statistically significant prognostic factor (P =.03), with inferior outcomes observed in infants and children 9 years or older. Patients who tolerated 25 or fewer weeks of asparaginase had a significantly worse outcome than those who received at least 26 weeks of asparaginase (P <.01, both univariate and multivariate). Older children (at least 9 years of age) were significantly more likely to have tolerated 25 or fewer weeks of asparaginase (P <.01). Treatment on Protocol 91-01 significantly improved the outcome of children with ALL, perhaps due to the prolonged asparaginase intensification and/or the use of dexamethasone. The inferior outcome of older children may be due, in part, to increased intolerance of intensive therapy.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Precursor Cell Lymphoblastic Leukemia-Lymphoma/drug therapy , Adolescent , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/standards , Antineoplastic Combined Chemotherapy Protocols/toxicity , Asparaginase/administration & dosage , Asparaginase/standards , Asparaginase/toxicity , Child , Child, Preschool , Clinical Protocols , Dexamethasone/administration & dosage , Dexamethasone/standards , Dexamethasone/toxicity , Disease-Free Survival , Doxorubicin/administration & dosage , Doxorubicin/standards , Doxorubicin/toxicity , Female , Follow-Up Studies , Humans , Infant , Infant, Newborn , Male , Risk Factors , Treatment Outcome
15.
J Cell Sci ; 114(Pt 5): 909-16, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11181174

ABSTRACT

Stathmin is a major cytosolic phosphoprotein that plays an important role in the regulation of microtubule dynamics during cell cycle progression. It has recently been proposed that the major function of stathmin is to promote depolymerization of the microtubules that make up the mitotic spindle. In this report, we tested the prediction that a deficiency in stathmin expression would result in constitutive stabilization of microtubules and lead to abnormalities in the organization of the mitotic spindle. Our studies demonstrate that antisense inhibition of stathmin expression in K562 erythroleukemic cells results in increased ratio of polymerized to depolymerized tubulin. These changes are associated with phenotypic abnormalities of the mitotic spindle and difficulty in completing mitosis. These studies also showed that inhibition of stathmin expression results in increased susceptibility of K562 leukemic cells to the pharmacological agents, like taxol, which are known to stabilize the mitotic spindle. In contrast, stathmin inhibition results in decreased sensitivity to vinblastine, an agent that destabilizes the mitotic spindle. Thus, our experimental findings are supportive of the model that stathmin is a microtubule-destabilizing factor that plays an important role in the regulation of the mitotic spindle. We also suggest a potential therapeutic approach for cancer based on the combination of stathmin inhibition with pharmacologic agents that stabilize the mitotic spindle.


Subject(s)
Microtubule Proteins , Phosphoproteins/antagonists & inhibitors , Spindle Apparatus , Biopolymers , Humans , Phenotype , Phosphoproteins/physiology , Stathmin , Tubulin/metabolism , Tumor Cells, Cultured
16.
J Infect Dis ; 183(4): 589-95, 2001 Feb 15.
Article in English | MEDLINE | ID: mdl-11170984

ABSTRACT

Hepatitis C virus (HCV) and human immunodeficiency virus type 1 (HIV-1) coinfection is common in hemophiliacs and injection drug users. To assess the interaction between HCV load and HIV-1 disease progression, we examined 207 HIV-1/HCV-coinfected patients. Patients were followed prospectively for approximately 7 years, and annual measurements of CD4(+) cell counts and HCV and HIV-1 loads were obtained. Survival analysis was used to define the independent effects of HCV load on HIV-1 progression. After controlling for CD4(+) cell count and HIV-1 RNA level, every 10-fold increase in baseline HCV RNA was associated with a relative risk (RR) for clinical progression to acquired immunodeficiency syndrome (AIDS) of 1.66 (95% confidence interval [CI], 1.10-2.51; P=.016) and an RR for AIDS-related mortality of 1.54 (95% CI, 1.03-2.30; P=.036). These findings emphasize the need for further research regarding the use of HIV-1- and HCV-specific therapy in coinfected individuals.


Subject(s)
HIV Infections/complications , Hemophilia A/virology , Hepacivirus/physiology , Hepatitis C/complications , Viral Load , Adolescent , Adult , CD4 Lymphocyte Count , Child , Disease Progression , HIV Infections/mortality , HIV Infections/virology , HIV-1/physiology , Hepatitis C/virology , Humans , Prospective Studies , RNA, Viral/blood
17.
Cancer Res ; 60(13): 3537-41, 2000 Jul 01.
Article in English | MEDLINE | ID: mdl-10910066

ABSTRACT

Stathmin is an abundant cytosolic phosphoprotein that plays an important role in the regulation of cellular proliferation. Its major function is to promote depolymerization of the microtubules that make up the mitotic spindle. Taxol is an effective chemotherapeutic agent whose activity is mediated through stabilization of the microtubules of the mitotic spindle. We demonstrate that antisense inhibition of stathmin expression chemosensitizes K562 leukemic cells to the antitumor effects of Taxol and results in a synergistic inhibition of their growth and clonogenic potential. In the presence of stathmin inhibition, exposure to Taxol results in more severe mitotic abnormalities (hypodiploidy and multinucleation). This, in turn, results in increased apoptosis of the aneuploid cells during subsequent cell division cycles. This novel molecular-based therapeutic approach may provide an effective form of cancer therapy that would avoid the severe toxicities associated with the use of multiple chemotherapeutic agents with overlapping toxicity profiles.


Subject(s)
Apoptosis/drug effects , Microtubule Proteins , Oligodeoxyribonucleotides, Antisense/toxicity , Paclitaxel/toxicity , Phosphoproteins/genetics , Spindle Apparatus/drug effects , Cell Division/drug effects , Doxorubicin/toxicity , Fluorouracil/toxicity , Humans , K562 Cells , Phosphoproteins/antagonists & inhibitors , Recombinant Proteins/antagonists & inhibitors , Recombinant Proteins/metabolism , Stathmin , Tetrahydrofolate Dehydrogenase/genetics , Tetrahydrofolate Dehydrogenase/metabolism , Transfection , Tumor Stem Cell Assay
18.
Blood Coagul Fibrinolysis ; 11(3): 255-9, 2000 Apr.
Article in English | MEDLINE | ID: mdl-10870806

ABSTRACT

This open-label, emergency-use study evaluated the efficacy and safety of activated human coagulation factor VIIa (recombinant) (rFVIIa) (NovoSeven; Novo Nordisk Pharmaceuticals, Inc., New Jersey, USA) in treating limb-threatening joint or muscle bleeds in 17 patients with haemophilia A or B and six patients with acquired inhibitors to factor VIII or factor IX. All patients had previously failed on one or more alternative therapies. rFVIIa administration was effective or partially effective in controlling joint or muscle bleeds in 34 out of 35 (97%) bleeding episodes; in 23 patients, 14 of 17 (82%) muscle bleeds and 16 of 18 (89%) joint bleeds were effectively controlled. These findings suggest that rFVIIa is an effective and well-tolerated therapeutic option in the management of joint or muscle haemorrhage in patients with haemophilia and in patients with acquired inhibitors.


Subject(s)
Factor VII/administration & dosage , Hemophilia A/drug therapy , Hemophilia B/drug therapy , Adolescent , Adult , Aged , Antibodies/blood , Child , Child, Preschool , Extremities/physiopathology , Factor IX/immunology , Factor VIII/immunology , Factor VIIa , Female , Hemophilia A/blood , Hemophilia A/immunology , Hemophilia A/physiopathology , Hemophilia B/blood , Hemophilia B/immunology , Hemophilia B/physiopathology , Hemorrhage/drug therapy , Humans , Infant , Injections, Intravenous , Male , Middle Aged , Recombinant Proteins/administration & dosage , Salvage Therapy
19.
Haemophilia ; 5(5): 354-9, 1999 Sep.
Article in English | MEDLINE | ID: mdl-10583518

ABSTRACT

This longitudinal study examines differences in hepatitis B immune titres in children and adolescents with haemophilia to determine if they are dependent on how immunity was acquired (vaccination or natural infection), and whether they are related to the child's HIV status and/or are influenced by HIV disease progression. Serologic titres (HBcAb, HBsAb) and HBsAg were measured prospectively at baseline, and at years 1, 2 and 3 of follow-up in 126 HIV- and 207 HIV+ children and adolescents with haemophilia. Analyses were performed to assess the impact of HIV status on the measured titres, and for HIV+ subjects to examine the association with CD4+ lymphocyte counts and p24 antigen status. The results show that HIV+ children were more likely than HIV- children to lose vaccine-induced immunity as indicated by the loss of HBsAb. There was an increased risk of losing HBsAb with higher CD4+ counts and younger age. Re-immunization was not successful in seven of eight HIV+ children. Two subjects (one HIV+, one HIV-) entered the study HBsAg- but became HBsAg+ over the course of follow-up. Seven HIV+ subjects lost natural immunity as indicated by the loss of HBcAb. The loss of either HBsAb or HBcAb in HIV--subjects was negligible to absent. In conclusion, because of the loss of immunity in HIV+ children the viral safety of factor replacement concentrates for these children is an important consideration. HIV- children rarely lose immunity, therefore frequent measures of HBsAb are not necessary.


Subject(s)
HIV Seronegativity , HIV Seropositivity/complications , Hepatitis B/blood , CD4 Lymphocyte Count , CD4-Positive T-Lymphocytes/cytology , Child , Child, Preschool , HIV Seronegativity/immunology , HIV Seropositivity/immunology , Hepatitis B/complications , Humans , Immune Tolerance , Immunity , Male
20.
Gerontologist ; 39(6): 729-35, 1999 Dec.
Article in English | MEDLINE | ID: mdl-10650683

ABSTRACT

The physical and mental benefits of exercise are universally recognized, but seldom available to persons with early to moderate stage dementia. Difficulty in initiating and maintaining purposeful behavior, coupled with the inability to travel independently, preclude most community-dwelling dementia sufferers from accessing organized fitness programs. Overburdened caregivers typically lack the inclination and know how to structure and supervise systematic exercise sessions. The University of Arizona Elder Rehab program offers independent study credit to students who serve as rehab partners and fitness supervisors to noninstitutionalized persons with dementia. In addition to regular aerobics and weight training workouts, participants engage in supervised volunteer work and memory- and language-stimulation activities with their student partners. Multiple benefits accrue to all participants. The program is cost effective, easily replicated, and may also be suitable for frail and depressed elderly persons without dementia.


Subject(s)
Alzheimer Disease/rehabilitation , Caregivers/organization & administration , Exercise Therapy/education , Health Services for the Aged/organization & administration , Students , Academic Medical Centers , Affect , Aged , Aged, 80 and over , Alzheimer Disease/psychology , Arizona , Education, Professional , Educational Measurement , Exercise , Female , Frail Elderly , Humans , Male , Outcome Assessment, Health Care , Weight Lifting , Workforce
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