PubMed Health⌕ Search

Biomedical subjects

Sharon B Murphy

Publications and source records attributed to Sharon B Murphy.

10 recordsLinked to original sources
PubMed2006

End points to establish the efficacy of new agents in the treatment of acute leukemia.

Federal regulations provide 2 pathways for approval of new agents for the treatment of acute leukemia, regular and accelerated approval. Regular approval requires evidence of clinical benefit, which is generally defined as either prolongation of life or improved quality of life, or an effect on an end point established as a surrogate for clinical benefit. Accelerated approval can be obtained based on demonstration of an effect on a surrogate measure "reasonably likely" to predict clinical benefit, but requires demonstration of clinical benefit after approval as well. The acute leukemias are a heterogeneous and relatively uncommon group of diseases. The design and execution of prospective randomized clinical trials demonstrating prolongation of life or improved quality of life for patients with these disorders can be difficult and costly and require lengthy follow-up. Thus, the development of novel trial design and inclusion of validated surrogate markers for clinical benefit are needed. To explore some of the issues pertinent to the choice of end points for drug approval in acute leukemia, the Food and Drug Administration invited the American Society of Hematology to participate in the organization and conduct of a joint workshop. In this report, we present the results of that effort.

Acute Disease↗
PubMed2005

Advanced-stage large-cell lymphoma in children and adolescents: results of a randomized trial incorporating intermediate-dose methotrexate and high-dose cytarabine in the maintenance phase of the APO regimen: a Pediatric Oncology Group phase III trial.

PURPOSE: The Pediatric Oncology Group adopted a histology-based approach to non-Hodgkin's lymphoma and treated patients with advanced large-cell lymphoma on a separate protocol (doxorubicin, vincristine, prednisone, 6-mercaptopurin, and methotrexate; APO regimen). In this study, we assessed the effects of an intense antimetabolite therapy alternating with APO on overall survival (OS) and event-free survival (EFS) and looked into biologic correlates. PATIENTS AND METHODS: From December 1994 to April 2000, we enrolled 180 eligible pediatric patients with stage III/IV large-cell lymphoma (LCL); 90 patients were randomly assigned to the intermediate-dose methotrexate (IDM) and high-dose cytarabine (HiDAC) arm, 85 patients to the APO arm, and five patients directly to the APO arm by study design due to CNS involvement. Planned therapy duration was 12 months. RESULTS: The 4-year EFS for all patients was 67.4% (SE, 4.2%), and OS was 80.1% (SE, 3.6%) without any significant difference between the two arms. The 4-year EFS and OS were 71.8% (SE, 6.1%) and 88.1% (SE, 4.4%), respectively, for patients with anaplastic large-cell lymphoma, and 63.8% (SE, 10.3%) and 70.3% (SE, 9.0%), respectively, for patients with diffuse large B-cell lymphoma. Only 11 patients required radiation (due to unresponsive bulky disease or CNS involvement). The IDM/HiDAC arm was associated with more toxicity. CONCLUSION: The efficacy of incorporating IDM/HiDAC in the treatment plan of pediatric and adolescent patients with advanced-stage LCL was inconclusive as to its effect on EFS, regardless of the lymphoma phenotype. It cannot be excluded that with a higher number of patients, one treatment could prove superior and future studies will build on these data.

Adolescent↗
PubMed2003

Risk factors for pediatric human immunodeficiency virus-related malignancy.

CONTEXT: Although cancers occur with increased frequency in children with human immunodeficiency virus (HIV) infection, the specific clinical, immunological, and viral risk factors for malignancy have not been identified. OBJECTIVE: To identify risk factors for malignancy among HIV-infected children. DESIGN, SETTING, AND PATIENTS: A multicenter case-control study of children with HIV at 26 institutions participating in the Pediatric Oncology Group. Forty-three case patients with a new malignancy and 74 control patients without a malignancy were matched based on the duration of their infection. Patients were enrolled between January 1992 and July 1998. MAIN OUTCOME MEASURES: Clinical and laboratory factors assessed as putative risk factors included demographic characteristics, HIV characteristics, prior antiretroviral treatment, and CD4 cell count. Coviral infections with Epstein-Barr virus (EBV), cytomegalovirus, and human herpesvirus 6 were assessed by semiquantitative polymerase chain reaction assays and serological testing. RESULTS: Case malignancy diagnoses included 28 non-Hodgkin lymphoma, 4 B-cell acute lymphoblastic leukemia, 1 Hodgkin disease, 8 leiomyosarcoma, 1 hepatoblastoma, and 1 schwannoma. Epstein-Barr virus viral load of more than 50 viral genome copies per 105 peripheral blood mononuclear cells was strongly associated with cancer risk but only for children with CD4 cell counts of at least 200/ microL (odds ratio [OR], 11.33; 95% confidence interval [CI], 2.09-65.66, P<.001). High EBV viral load was not associated with cancer for children with CD4 cell counts of less than 200/ microL (OR, 1.12; 95% CI, 0.13-9.62; P =.99). Zidovudine antiretroviral therapy did not confer a significant protective effect for either the high (OR, 0.81; 95% CI, 0.22-3.09; P =.77) or the low CD4 cell count groups (OR, 0.27; 95% CI, 0.04-1.46; P =.16). The route of HIV infection was not associated with increased cancer risk. CONCLUSIONS: Route of infection, demographic characteristics, and zidovudine use were not associated with the development of malignancy in HIV-infected children. High viral burden with EBV was associated with the development of malignancy in HIV-infected children although the effect was modified by CD4 cell count. The pathogenesis of HIV-related pediatric malignancies remains unclear and other contributing risk factors can be elucidated only through further study.

Antiviral Agents↗
PubMed2003

Results of little or no treatment for lymphocyte-predominant Hodgkin disease in children and adolescents.

PURPOSE: The nodular lymphocyte-predominant form of Hodgkin disease (LPHD) is a distinct clinicopathologic entity with a favorable prognosis. To see if children and adolescents could be spared the adverse sequelae of treatment, the authors adopted a policy of little or no treatment of localized LPHD in 1989. PATIENTS AND METHODS: Presentation, pathology, and outcomes were reviewed for 15 consecutive children and adolescents with LPHD seen at a single institution since 1989. One patient was lost to follow-up and two patients were seen only once in consultation and treated elsewhere. These three cases were excluded, leaving twelve: nine males and three females, ranging in age at diagnosis from 2 to 17 years (median 11). Eleven of the 12 had stage I disease, and 1 had stage II. Six received no treatment following excisional biopsy, while five received a brief treatment with chemotherapy only. One was initially treated with involved field radiotherapy (IFRT) due to an initially imprecise histologic diagnosis of classic Hodgkin disease. RESULTS: All patients are alive, without evidence of disease, for periods ranging from 2 to 13+ years after diagnosis (median 6 years). One patient recurred locally with LPHD 6 years after initial brief chemotherapy and was then treated with IFRT, achieving a prolonged second remission. CONCLUSION: Children and adolescents with localized LPHD have an excellent prognosis and may be safely approached either with a wait-and-see attitude of no initial therapy after initial adenectomy or with less aggressive treatments.

Adolescent↗
PubMed2002

Results of a randomized phase III trial in children and adolescents with advanced stage diffuse large cell non-Hodgkin's lymphoma: a Pediatric Oncology Group study.

PURPOSE: The Pediatric Oncology Group (POG) adopted a histology-based approach to the management of pediatric non-Hodgkin's lymphomas (NHL) utilizing the National Cancer Institute Working Formulation for Clinical Usage. Patients with diffuse large cell lymphoma (DLCL) were treated on a separate protocol from small cell diffuse undifferentiated or lymphoblastic lymphomas. This study assessed the overall and event free survival of children with DLCL and determined the effects of cyclophosphamide upon these end-points in a prospective randomized trial. PATIENTS AND METHODS: One hundred and twenty eligible stage III or IV NHL patients with the confirmed diagnosis of diffuse large cell or immunoblastic histology were enrolled on study between October 1986 and November 1991. Patients were randomized to receive or not receive cyclophosphamide: 58 received cyclophosphamide, doxorubicin, vincristine, 6-mercaptopurine (6-MP), and prednisone (ACOP+) and 62 were treated with doxorubicin, vincristine, 6-MP, and prednisone (APO). In both treatment programs methotrexate was substituted when the doxorubicin cumulative dose reached 450 mg/m2. Radiation was administered to bulky disease if progression or no response were observed after induction therapy. Planned duration of therapy was 12 months. RESULTS: The 5-year event free survival (EFS) rates of patients treated with ACOP+ versus APO were 62+/-7 and 72+/-6%, respectively. While there was no statistically significant difference between the two treatment arms (p = 0.28), we can only say that we are 95% confident that the difference in 5-year EFS falls in the wide range from 28% in favor of APO to 8% favoring ACOP+. Marrow suppression was the main toxicity with one fatal infection. There were three other deaths on study due to respiratory failure in patients with mediastinal masses. Only one patient experienced cardiotoxicity requiring discontinuation of doxorubicin. Ten patients received radiation therapy to achieve remission. CONCLUSION: The efficacy of elimination of cyclophosphamide from the treatment program of children and adolescents with advanced stage diffuse large cell lymphoma was inconclusive as to its effect on EFS. Furthermore, the majority of the patients (92%) did not require any radiation therapy to bulky disease indicating that the chemotherapy regimens are quite efficient for achievement of complete remission.

Adolescent↗
PubMed2002

Human herpesvirus 6 and cytomegalovirus infections in children with human immunodeficiency virus infection and cancer.

AIM: Measure the prevalence of human herpesvirus 6 (HHV-6) and cytomegalovirus (CMV) infections in children and adolescents with HIV infection and malignancy. METHODS: Semiquantitative polymerase chain reaction and serology were used to test for HHV-6 and CMV infections in 31 cases (HIV-infected children with cancer), 56 HIV controls (HIV-infected children without cancer) and 30 cancer controls (HIV-uninfected children with cancer). RESULTS: In cases, HIV controls and cancer controls, HHV-6 DNA was detected in 29, 39 and 34%, respectively, and CMV DNA was detected in 13, 4 and 7%, respectively. Four cases (13%) and no HIV controls or cancer controls harbored HHV-6 subtype A (P = 0.014). In cases, HIV controls and cancer controls, the prevalence of HHV-6 antibodies was 58, 68 and 93%, respectively, and the prevalence of CMV antibodies was 71, 48 and 70%, respectively. HHV-6 seroprevalence was lower in cases than in cancer controls (P = 0.002), even with adjustments for age and CD4 concentrations; however, HHV-6 infection rates (presence of HHV-6 DNA and/or HHV-6 antibodies) were similar in all groups. Stratification showed that CMV infection was more common in younger patients (ages < 8 years) without severe immune suppression (CD4 concentration >200 cells/microl) than in HIV controls (odds ration, 10.343; 95% confidence interval, 1.65, 121.57). Geometric mean titers of serum anti-CMV antibodies, but not anti-HHV-6 antibodies, were higher in cases (1:71) than in HIV controls (1:33) (P = 0.005). CONCLUSIONS: HHV-6 and CMV infections were common among children with HIV infection and cancer. CMV seropositivity also was associated with cancer in younger HIV-infected patients who did not have severe immune suppression. HHV-6A was detected only in HIV-infected children with cancer.

Adolescent↗
PubMedDate not supplied

Clinical trials in children.

The imperative to undertake randomised trials in children arises from extraordinary advances in basic biomedical sciences, needing a matching commitment to translational research if child health is to reap the benefits from this new knowledge. Unfortunately, many prescribed treatments for children have not been adequately tested in children, sometimes resulting in harmful treatments being given and beneficial treatments being withheld. Government, industry, funding agencies, and clinicians are responsible for research priorities being adult-focused because of the greater burden of disease in adults, coupled with financial and marketing considerations. This bias has meant that the equal rights of children to participate in trials has not always been recognised. This is changing, however, as the need for clinical trials in children has been increasingly recognised by the scientific community and broader public, leading to new legislation in some countries making trials of interventions mandatory in children as well as adults before drug approval is given. Trials in children are more challenging than those in adults. The pool of eligible children entering trials is often small because many conditions are uncommon in children, and the threshold for gaining consent is often higher and more complex because parents have to make decisions about trial participation on behalf of their child. Uncertain about what is best, despite supporting the notion of trials in principle, parents and paediatricians generally opt for the new intervention or for standard care rather than trial participation. In this review, we explore issues relating to trial participation for children and suggest some strategies for improving the conduct of clinical trials involving children.

Child↗