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Dive into the research topics where Karen T. Tashima is active.

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Featured researches published by Karen T. Tashima.


The New England Journal of Medicine | 1999

Efavirenz plus Zidovudine and Lamivudine, Efavirenz plus Indinavir, and Indinavir plus Zidovudine and Lamivudine in the Treatment of HIV-1 Infection in Adults

Schlomo Staszewski; Javier Morales-Ramirez; Karen T. Tashima; Anita Rachlis; Daniel J. Skiest; James Stanford; Richard Stryker; Philip C. Johnson; Dominic Labriola; Dianne Farina; Douglas Manion; Nancy M. Ruiz

BACKGROUND Efavirenz is a nonnucleoside reverse-transcriptase inhibitor of human immunodeficiency virus type 1 (HIV-1). We compared two regimens containing efavirenz, one with a protease inhibitor and the other with two nucleoside reverse-transcriptase inhibitors, with a standard three-drug regimen. METHODS The study subjects were 450 patients who had not previously been treated with lamivudine or any nonnucleoside reverse-transcriptase inhibitor or protease inhibitor. In this open-label study, patients were randomly assigned to one of three regimens: efavirenz (600 mg daily) plus zidovudine (300 mg twice daily) and lamivudine (150 mg twice daily); the protease inhibitor indinavir (800 mg every eight hours) plus zidovudine and lamivudine; or efavirenz plus indinavir (1000 mg every eight hours). RESULTS Suppression of plasma HIV-1 RNA to undetectable levels was achieved in more patients in the group given efavirenz plus nucleoside reverse-transcriptase inhibitors than in the group given indinavir plus nucleoside reverse-transcriptase inhibitors (70 percent vs. 48 percent, P<0.001). The efficacy of the regimen of efavirenz plus indinavir was similar (53 percent) to that of the regimen of indinavir, zidovudine, and lamivudine. CD4 cell counts increased significantly with all combinations (range of increases, 180 to 201 cells per cubic millimeter). More patients discontinued treatment because of adverse events in the group given indinavir and two nucleoside reverse-transcriptase inhibitors than in the group given efavirenz and two nucleoside reverse-transcriptase inhibitors (43 percent vs. 27 percent, P=0.005). CONCLUSIONS As antiretroviral therapy in HIV-1-infected adults, the combination of efavirenz, zidovudine, and lamivudine has greater antiviral activity and is better tolerated than the combination of indinavir, zidovudine, and lamivudine.


Clinical Infectious Diseases | 2003

Guidelines for the Evaluation and Management of Dyslipidemia in Human Immunodeficiency Virus (HIV)-Infected Adults Receiving Antiretroviral Therapy: Recommendations of the HIV Medicine Association of the Infectious Disease Society of America and the Adult AIDS Clinical Trials Group

Michael P. Dubé; James H. Stein; Judith A. Aberg; Carl J. Fichtenbaum; John G. Gerber; Karen T. Tashima; W. Keith Henry; Judith S. Currier; Dennis L. Sprecher; Marshall J. Glesby

Michael P. Dube, James H. Stein, Judith A. Aberg, Carl J. Fichtenbaum, John G. Gerber, Karen T. Tashima, W. Keith Henry, Judith S. Currier, Dennis Sprecher, and Marshall J. Glesby, for the Adult AIDS Clinical Trials Group Cardiovascular Subcommittee Indiana University, Indianapolis; University of Wisconsin, Madison; Washington University, St. Louis, Missouri; University of Cincinnati and Cleveland Clinic, Ohio; University of Colorado, Denver; Brown University, Providence, Rhode Island; University of Minnesota, St. Paul; University of California at Los Angeles; and Cornell University, New York, New York


Clinical Infectious Diseases | 2005

Guidelines for the Management of Chronic Kidney Disease in HIV-Infected Patients: Recommendations of the HIV Medicine Association of the Infectious Diseases Society of America

Samir Gupta; Joseph A. Eustace; Jonathan A. Winston; Ivy I. Boydstun; Tejinder S. Ahuja; Rudolph A. Rodriguez; Karen T. Tashima; Michelle E. Roland; Nora Franceschini; Frank J. Palella; Jeffrey L. Lennox; Paul E. Klotman; Sharon Nachman; Stephen D. Hall; Lynda A. Szczech

Samir K. Gupta, Joseph A. Eustace, Jonathan A. Winston, Ivy I. Boydstun, Tejinder S. Ahuja, Rudolph A. Rodriguez, Karen T. Tashima, Michelle Roland, Nora Franceschini, Frank J. Palella, Jeffrey L. Lennox, Paul E. Klotman, Sharon A. Nachman, Stephen D. Hall, and Lynda A. Szczech Divisions of Infectious Diseases and Clinical Pharmacology, Department of Medicine, Indiana University School of Medicine, Indianapolis; Division of Nephrology, Johns Hopkins University, School of Medicine and Department of Epidemiology, Bloomberg School of Public Health, Baltimore, Maryland; Division of Nephrology, Department of Medicine, Mount Sinai School of Medicine, New York, and Division of Nephrology and Hypertension and Division of Infectious Diseases, Department of Pediatrics, State University of New York, Stony Brook; Division of Nephrology, Department of Medicine, University of Texas Medical Branch, Galveston; Division of Nephrology, Department of Medicine, San Francisco General Hospital and Positive Health Program at San Francisco General Hospital and the UCSF AIDS Research Institute, Department of Medicine, University of California at San Francisco; Division of Infectious Diseases, Department of Medicine, The Miriam Hospital, Brown Medical School, Providence, Rhode Island; Division of Nephrology and Hypertension, Department of Medicine, University of North Carolina at Chapel Hill, and Duke Clinical Research Institute and the Division of Nephrology, Department of Medicine, Duke University Medical Center, Durham, North Carolina; Division of Infectious Diseases, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois; and Grady Infectious Disease Program, Division of Infectious Diseases, Department of Medicine, Emory University, Atlanta, Georgia


Annals of Internal Medicine | 2005

Impact of Efavirenz on Neuropsychological Performance and Symptoms in HIV-Infected Individuals

David B. Clifford; Scott R. Evans; Yijun Yang; Edward P. Acosta; Karl Goodkin; Karen T. Tashima; David M. Simpson; David M. Dorfman; Heather J. Ribaudo; Roy M. Gulick

Context Neurologic toxicity is the most commonly reported adverse effect of the antiretroviral drug efavirenz. Contribution In this substudy of a randomized, controlled trial, 12 of 200 (6%) HIV-infected individuals discontinued treatment with efavirenz because of central nervous system symptoms or mood disorders versus 0 of 103 individuals (0%) who were not receiving the drug. Although patients taking efavirenz had more neuropsychological symptoms, such as bad dreams, in the first week of therapy, no statistically significant neuropsychological differences were found at weeks 4, 12, and 24. Implications Some adverse neuropsychological effects associated with efavirenz are probably transient. The Editors Efavirenz is a non-nucleoside reverse transcriptase inhibitor approved for treatment of HIV infection. The drug is potent, is generally well tolerated, and can be administered once daily, making it a preferred treatment option for HIV infection (1, 2). The most commonly reported adverse effect with efavirenz is neurologic toxicity, with more than 50% of patients reporting symptoms in open-label studies (1, 3). Our randomized, controlled study prospectively characterized aspects of the neurologic toxicity of 3 protease inhibitorsparing antiretroviral regimens for the initial treatment of HIV infection. Methods This investigator-initiated trial was a substudy of the AIDS Clinical Trials Group study A5095, a randomized, double-blind trial of 3 antiretroviral regimens: zidovudine and lamivudine in combination with efavirenz; abacavir; or abacavir and efavirenz in combination (4). For simplicity, we will refer to 2 groups: patients who received efavirenz (with or without abacavir) and those who did not. Randomization was performed centrally without reference to center. The study was supported by the National Institutes of Health (NIH) and was approved by the institutional review boards at each of the participating institutions, with each patient providing informed consent to participate in the substudy. All patients at sites taking part in the substudy were invited to participate before randomization for the parent study (Figure 1). Unblinding and within-class substitutions were allowed in cases of treatment-limiting toxicity (we substituted stavudine for zidovudine, didanosine for abacavir, and nevirapine for efavirenz). Participants had not previously received antiretroviral therapy, and their baseline plasma HIV-1 RNA levels were greater than 400 copies/mL. Parent study A5095 enrolled 1147 participants, of whom 303 at 36 clinical trials units volunteered to participate in the additional evaluations for A5097s. Participants were recruited between March 2001 and January 2002. Figure 1. CONSORT diagram of substudy 5097s. The primary measures of neuropsychological performance were the Trail Making Tests (Parts A and B) and the Digit Symbol Substitution Test (part of the Wechsler Adult Intelligence Scale III [5]). A summary neuropsychological Z score (NPZ3) was derived from the sum of the scores from these 3 tests and standardized for age. Positive scores indicated above-normal function, whereas negative scores indicated below-normal function. The entire score was coded as missing if any component of the NPZ3 was not available. The Neurologic AIDS Research Consortium provided administrator training at each site. These tests assessed functioning in the areas of motor persistence, sustained attention, response speed, visuomotor coordination, and conceptual shifting and tracking. Neuropsychometric measures were collected at baseline and at weeks 1, 4, 12, and 24. Testing was performed at each time point to assess symptoms that might be associated with efavirenz use, sleep disorders, anxiety, depression, and history of drug abuse. The instruments are summarized in Table 1. The symptom questionnaire developed for this study is shown in the Appendix Figure. Appendix Figure. Sample participant questionnaire. Table 1. Testing Instruments Whole blood was collected from all participants to determine efavirenz trough concentrations in plasma (13). These data were used to explore relationships between drug exposure and other variables that were evaluated in the study. Statistical Analysis Our substudy was designed to compare neurologic changes from baseline in patients who received efavirenz with changes in those who did not. The study had 90% power to detect a standard deviation of 0.4 for change in the summary neuropsychological performance score from baseline to week 1. We presented descriptive statistics for the study sample and used nonparametric tests to determine treatment differences. Using the nonparametric methods of Hodges and Lehmann (14) and Proc-StatXact software, version 4.0.1 (Cytel Software Corp., Cambridge, Massachusetts), we estimated treatment differences for continuous outcomes with corresponding exact confidence intervals. Generalized estimating equation modeling (a regression method) and the Wei-Johnson test (a nonparametric method for analyzing incomplete 2-sample data) (15) were used to compare treatment groups longitudinally; both methods assumed that data were missing completely at random. We used the Spearman correlation coefficient, a rank-based method that is robust to extreme observations, to evaluate correlations. All significance testing was performed at an level of 0.05 with no adjustment for multiple testing. All reported P values were 2-sided. To assess the potential effect of any missing data, we performed multiple imputation, analyzed 2 worst-case scenarios (Appendix Table 1 and Appendix Table 2), and conducted an as-treated analysis that excluded patients who discontinued efavirenz therapy. We used SAS software (SAS Institute, Inc., Cary, North Carolina) to perform statistical analyses. Test sources included Elsevier Science (Oxford, United Kingdom) for the Pittsburgh Sleep Quality Index, Mind Garden (Redwood City, California) for the State-Trait Anxiety Inventory for Adults, and the National Institute of Mental Health (Bethesda, Maryland) for the Center for Epidemiologic Studies Depression Scale. Role of the Funding Sources This investigator-initiated protocol was supported by the NIH. Drugs used in the study were donated by pharmaceutical companies whose representatives participated in team discussions. The study was monitored by NIH-contracted monitors and was supervised by a data safety monitoring committee that was appointed by the National Institute of Allergy and Infectious Diseases. The NIH-supported biostatistical team working with the AIDS Clinical Trials Group and the Neurologic AIDS Research Consortium performed the statistical analyses. The protocol team, led by the first author, had final responsibility for the study protocol, case report forms, statistical analysis plan, progress of the study, analysis, and reporting of the data, regardless of outcome. The final version was the sole responsibility of the authors. The team had full access to the data files of the study. Results Baseline Evaluations Recruitment characteristics are displayed in Figure 1; demographic characteristics of the study participants are presented in Table 2. The treatment groups were balanced at baseline with respect to demographic characteristics, neuropsychological measures, and responses to the symptom questionnaire. The sleep disturbance component of the global sleep index demonstrated a baseline difference; the patients who eventually received efavirenz had marginally more sleep disturbances (P= 0.048) (data not shown). Other components of the sleep index, including quality, latency, duration, efficiency, use of sleeping medication, and daytime dysfunction, were similar between groups. Alcohol abuse, drug use, and affective disturbances were infrequent and similar for both groups. Table 2. Baseline Characteristics and Evaluations by Treatment Group Disposition of Study Participants The study allowed for drug substitution from the same class of antiretroviral agents in cases of treatment-limiting toxicity. Table 3 summarizes the modifications that occurred and the respective reasons. Appendix Table 3 gives further details of timing of modifications and the ethnicity of the individuals. Primary end point data (the change in NPZ3 from baseline to week 1) were observed in 283 of the 303 (93.4%) participants. Table 3. Reasons for Modification of Treatment Appendix Table 1. Neuropsychological Performance Appendix Table 2. Results of Sensitivity Analysis by Generalized Estimating Equation Method Appendix Table 3. Status and Ethnicity of Patients Requiring Modification of Treatment Prospective Evaluations Median NPZ3 scores improved in both groups during the study, with the greatest change occurring in the first week of treatment (Figure 2). No statistically significant differences in changes in neuropsychological performance were observed between the groups at any time point. We conducted conventional longitudinal analyses to further investigate differences in neuropsychological scores between the treatment groups. On the basis of these analyses, we had insufficient evidence to conclude that there were treatment differences (generalized estimating equation modeling in which treatment was the only independent variable and an exchangeable correlation structure was assumed, P= 0.176; Wei-Johnson test, P= 0.196). Multiple sensitivity analyses were performed, including single and multiple imputation methods, as-treated analyses, and 2 forms of worst-case scenarios. Details of these analyses are shown in Appendix Table 1. Multiple imputation and as-treated analyses generally provided similar results to observed data at specific weeks; however, the worst-case analyses at weeks 4, 12, and 24 displayed significant differences between groups. These results suggest that differences between groups might exist if the worst-case scenario were true, that is, if patients without data who were receiving efavirenz had wors


Clinical Infectious Diseases | 2006

Pharmacogenetics of Plasma Efavirenz Exposure after Treatment Discontinuation: An Adult AIDS Clinical Trials Group Study

Heather J. Ribaudo; David W. Haas; Camlin Tierney; Richard B. Kim; Grant R. Wilkinson; Roy M. Gulick; David B. Clifford; Catia Marzolini; Courtney V. Fletcher; Karen T. Tashima; Daniel R. Kuritzkes; Edward P. Acosta

BACKGROUND Efavirenz has a long plasma half-life and a low genetic barrier to resistance. Simultaneously stopping treatment with all agents in efavirenz-containing regimens may result in functional efavirenz monotherapy that selects for drug-resistant human immunodeficiency virus type 1. Lower plasma efavirenz clearance is associated with a cytochrome P450 2B6 gene (CYP2B6) polymorphism (516G-->T) that is more frequent among African American individuals than among European American individuals. METHODS We characterized relationships between this polymorphism and predicted plasma efavirenz concentration-time profiles after discontinuation of therapy with use of data obtained from subjects receiving therapy. Pharmacokinetic parameters were estimated using population-based methods. Concentrations after discontinuation of therapy were predicted from subject-specific estimates. RESULTS. Median estimated efavirenz half-lives were 23, 27, and 48 h for patients with CYP2B6 position 516 GG (78 patients), GT (60), and TT (14) genotypes, respectively (P<.001). After therapy was stopped, plasma efavirenz concentrations in patients with GG, GT, and TT genotypes were predicted to exceed 46.7 ng/mL (the estimated protein-adjusted 95% inhibitory concentration for wild-type virus) for a median of 5.8 days (interquartile range [IQR], 4.4-8.3 days), 7.0 days (IQR, 5.0-8.0 days), and 14 days (IQR, 11.1-21.2 days), respectively (P<.001). Plasma efavirenz levels were predicted to exceed 46.7 ng/mL for >21 days in 5% of subjects with GG genotype, 5% of subjects with GT genotype, and 29% of subjects with TT genotype. CONCLUSIONS The CYP2B6 position 516 TT genotype or a prolonged measured elimination half-life may predict increased risk of developing drug resistance among patients who discontinue efavirenz-containing regimens. This has implications for strategies to safely discontinue antiretroviral regimens while avoiding the emergence of drug resistance.


Clinical Infectious Diseases | 2000

Human Immunodeficiency Virus Infection, AIDS, and Smoking Cessation: The Time is Now

Raymond Niaura; William G. Shadel; Kathleen M. Morrow; Karen T. Tashima; Timothy P. Flanigan; David B. Abrams

Treatments for persons who are infected with human immunodeficiency virus (HIV) or who have developed AIDS have advanced to the point where death is no longer the inevitable outcome of diagnosis. Combination antiretroviral therapy has made HIV infection less of a terminal condition and more of a medically manageable chronic disease. Thus, efforts to improve the health status and quality of life of HIV-infected persons have become one of the highest treatment priorities for the next decade. Cigarette smoking is highly prevalent among HIV-infected persons, and quitting smoking would greatly improve the health status of these individuals. However, to date, no studies have evaluated the efficacy of a smoking-cessation intervention specifically tailored to this population. This article reviews the evidence and rationale for advancing smoking-cessation treatments specifically tailored to the needs of HIV-infected persons and provides recommendations for future treatment studies.


The Journal of Infectious Diseases | 2011

Abacavir/lamivudine versus tenofovir DF/emtricitabine as part of combination regimens for initial treatment of HIV: final results.

Paul E. Sax; Camlin Tierney; Ann C. Collier; Eric S. Daar; Katie Mollan; Chakra Budhathoki; Catherine Godfrey; Nasreen C. Jahed; Laurie Myers; David Katzenstein; Awny Farajallah; James F. Rooney; Belinda Ha; William C. Woodward; Judith Feinberg; Karen T. Tashima; Robert L. Murphy; Margaret A. Fischl

BACKGROUND AIDS Clinical Trials Group A5202 compared blinded abacavir/lamivudine (ABC/3TC) to tenofovir DF/emtricitabine (TDF/FTC) with efavirenz (EFV) or atazanavir/ritonavir (ATV/r) in human immunodeficiency virus (HIV)-infected treatment-naive patients, stratified by screening HIV RNA (< or ≥ 10(5) copies/mL). Due to higher virologic failure with ABC/3TC in the high HIV RNA stratum, blinded treatment was stopped in this group, but study follow-up continued for all patients. METHODS Primary endpoints were times to virologic failure, regimen modification, and safety event. RESULTS In the low HIV RNA stratum, time to virologic failure was similar for ABC/3TC vs TDF/FTC with ATV/r (hazard ratio [HR] 1.25, 95% confidence interval [CI] 0.76, 2.05) or EFV (HR 1.23, 95% CI 0.77, 1.96), with significantly shorter times to regimen modification for ABC/3TC with EFV or ATV/r and to safety events with EFV. Prior to stopping blinded treatment in the high stratum, higher virologic failure rates were seen with ABC/3TC with EFV (HR 2.46, 95% CI 1.20, 5.05) or ATV/r (HR 2.22, 95% CI 1.19, 4.14). CONCLUSIONS In the low HIV RNA stratum, times to virologic failure for ABC/3TC or TDF/FTC were not different with EFV or ATV/r. In the high stratum, virologic failure rate was significantly higher for ABC/3TC than for TDF/FTC when given with either EFV or ATV/r.


The Journal of Infectious Diseases | 1999

Cerebrospinal Fluid Human Immunodeficiency Virus Type 1 (HIV-1) Suppression and Efavirenz Drug Concentrations in HIV-1—Infected Patients Receiving Combination Therapy

Karen T. Tashima; Angela M. Caliendo; M. Ahmad; J. M. Gormley; W. D. Fiske; J. M. Brennan; Timothy P. Flanigan

Efavirenz, a potent inhibitor of human immunodeficiency virus type 1 (HIV-1) reverse transcriptase, is a promising addition to the antiretroviral armamentarium. Efavirenz levels and HIV-1 RNA levels were measured in cerebrospinal fluid (CSF) and plasma of 10 HIV-1-infected patients taking efavirenz, 600 mg daily, in combination with other antiretroviral medications. Efavirenz was detected in the CSF at a mean concentration of 35.1 nM (range, 6. 6-58.9 nM), which was above the IC95 for wild-type HIV-1. The mean CSF-to-plasma ratio was 0.61% (range, 0.26%-0.99%). CSF HIV-1 RNA levels were ascertained in 9 of the patients; all were <400 copies/mL after a mean of 26 weeks on therapy. Eight of the 9 patients had no detectable virus in plasma. These results indicate that efavirenz is present in the CSF at low levels and is effective in suppressing CSF viral levels when used in combination therapy.


AIDS | 2001

Neurocognitive performance enhanced by highly active antiretroviral therapy in HIV-infected women

Ronald A. Cohen; Robert J. Boland; Robert H. Paul; Karen T. Tashima; Ellie E. Schoenbaum; David D. Celentano; Paula Schuman; Dawn K. Smith; Charles C. J. Carpenter

ObjectiveTo determine whether highly active retroviral therapy (HAART) is associated with better neurocognitive outcome over time among HIV-infected women with severely impaired immune function. MethodsA semiannual neurocognitive examination on four tasks was administered: Color Trail Making, Controlled Oral Word Association, Grooved Pegboard and Four-Word Learning. This protocol was initiated in the HIV Epidemiological Research study (HERS) study when a womans CD4 cell count fell to < 100 × 106 cells/l. Immune function (CD4), viral load status and depression severity (CESD) were also assessed semi-annually, along with an interview to determine medication intake and illicit drug use. ResultsHAART was not available to any participant at the time of enrollment (baseline), while 44% reported taking HAART at their most recent visit (mean duration of HAART 36.3 ± 12.6 months). HAART-treated women had improved neurocognitive performance compared with those not treated with HAART. Women taking HAART for 18 months or more showed the strongest neurocognitive performance with improved verbal fluency, psychomotor and executive functions. These functions worsened among women not taking HAART. Substance abuse status, severity of depressive symptoms, age and educational level did not influence the HAART treatment effects on neurocognitive performance. Neurocognitive improvements were strongly associated with the magnitude of CD4 cell count increases. ConclusionsHAART appeared to produce beneficial effect on neurocognitive functioning in HIV-infected women with severely impaired immune systems. Benefits were greatest for women who reported receiving HAART for more than 18 months.


Aids Patient Care and Stds | 2003

The Impact of Apathy and Depression on Quality of Life in Patients Infected with HIV

David F. Tate; Robert H. Paul; Timothy P. Flanigan; Karen T. Tashima; Justin M. Nash; Christine Adair; Robert J. Boland; Ronald A. Cohen

Apathy refers to decreased self-initiation and goal-directed behavior. Apathy is a relatively common neuropsychiatric symptom associated with HIV, yet the impact of apathy on health-related quality of life (QOL) has not been investigated. We examined the relationship between apathy, depression, and QOL among individuals infected with HIV. Apathy was quantified using the Marin Apathy scale and QOL was measured with the Medical Outcomes Study Short-Form 36 (SF-36). Results of the study revealed that both apathy and depression were more common among patients with HIV than healthy control subjects. Twenty-six percent of the patients with HIV reported clinically significant apathy while 80% of the patients reported clinically significant depression. Apathy did not relate to ratings of overall QOL, but it was modestly associated with ratings of mental health and role disruption secondary to mental health. By contrast, ratings of depression were strongly related to overall QOL and most indices of SF-36. Regression equations revealed that depression and apathy independently contributed to mental health and role disruption secondary to mental health. Importantly, ratings of depression accounted for the majority of variance for ratings of QOL. The findings indicate that while apathy is more common among individuals with HIV compared to healthy control subjects, the impact of apathy on QOL is less significant than depression. Clinicians should continue to focus on depression as an important neuropsychiatric symptom associated with HIV.

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David F. Tate

University of Missouri–St. Louis

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