22 results on '"Crawford, KW"'
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2. Evaluation of treatment outcomes for patients on first-line regimens in US President's Emergency Plan for AIDS Relief ( PEPFAR) clinics in Uganda: predictors of virological and immunological response from RV288 analyses.
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Crawford, KW, Wakabi, S, Magala, F, Kibuuka, H, Liu, M, and Hamm, TE
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HIV infection prognosis , *ANTIRETROVIRAL agents , *ANALYSIS of covariance , *CHI-squared test , *CONFIDENCE intervals , *STATISTICAL correlation , *FISHER exact test , *HIV infections , *MEDICAL cooperation , *SCIENTIFIC observation , *RESEARCH , *RESEARCH funding , *STATISTICAL sampling , *STATISTICS , *DATA analysis , *VIRAL load , *MULTIPLE regression analysis , *TREATMENT effectiveness , *CROSS-sectional method , *EVALUATION of human services programs , *DATA analysis software , *STATISTICAL models , *DESCRIPTIVE statistics , *CD4 lymphocyte count , *ODDS ratio - Abstract
Objectives Viral load ( VL) monitoring is recommended, but seldom performed, in resource-constrained countries. RV288 is a US President's Emergency Plan for AIDS Relief ( PEPFAR) basic programme evaluation to determine the proportion of patients on treatment who are virologically suppressed and to identify predictors of virological suppression and recovery of CD4 cell count. Analyses from Uganda are presented here. Methods In this cross-sectional, observational study, patients on first-line antiretroviral therapy ( ART) (efavirenz or nevirapine + zidovudine/lamivudine) from Kayunga District Hospital and Kagulamira Health Center were randomly selected for a study visit that included determination of viral load ( HIV-1 RNA), CD4 cell count and clinical chemistry tests. Subjects were recruited by time on treatment: 6-12, 13-24 or > 24 months. Logistic regression modelling identified predictors of virological suppression. Linear regression modelling identified predictors of CD4 cell count recovery on ART. Results We found that 85.2% of 325 subjects were virologically suppressed (viral load < 47 HIV-1 RNA copies/ml). There was no difference in the proportion of virologically suppressed subjects by time on treatment, yet CD4 counts were higher in each successive stratum. Women had higher median CD4 counts than men overall (406 vs. 294 cells/μL, respectively; P < 0.0001) and in each time-on-treatment stratum. In a multivariate logistic regression model, predictors of virological suppression included efavirenz use [odds ratio ( OR) 0.47; 95% confidence interval ( CI) 0.22-1.02; P = 0.057], lower cost of clinic visits ( OR 0.815; 95% CI 0.66-1.00; P = 0.05), improvement in CD4 percentage ( OR 1.06; 95% CI 1.014-1.107; P = 0.009), and care at Kayunga vs. Kangulamira ( OR 0.47; 95% CI 0.23-0.92; P = 0.035). In a multivariate linear regression model of covariates associated with CD4 count recovery, time on highly active antiretroviral therapy ( ART) ( P < 0.0001), patient satisfaction with care ( P = 0.038), improvements in total lymphocyte count ( P < 0.0001) and haemoglobin concentration ( P = 0.05) were positively associated, whereas age at start of ART ( P = 0.0045) was negatively associated with this outcome. Conclusions High virological suppression rates are achievable on first-line ART in Uganda. The odds of virological suppression were positively associated with efavirenz use and improvements in CD4 cell percentage and total lymphocyte count and negatively associated with the cost of travel to the clinic. CD4 cell reconstitution was positively associated with CD4 count at study visit, time on ART, satisfaction with care at clinic, haemoglobin concentration and total lymphocyte count and negatively associated with age. [ABSTRACT FROM AUTHOR]
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- 2015
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3. Interleukin 6 Blockade With Tocilizumab Diminishes Indices of Inflammation That Are Linked to Mortality in Treated Human Immunodeficiency Virus Infection.
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Funderburg NT, Shive CL, Chen Z, Tatsuoka C, Bowman ER, Longenecker CT, McComsey GA, Clagett BM, Dorazio D, Freeman ML, Sieg SF, Moisi D, Anthony DD, Jacobson JM, Stein SL, Calabrese LH, Landay A, Flexner C, Crawford KW, Capparelli EV, Rodriguez B, and Lederman MM
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- Humans, Inflammation drug therapy, Lipids, Cross-Over Studies, HIV Infections drug therapy, Interleukin-6 metabolism
- Abstract
Background: People with human immunodeficiency virus (PWH) are at increased risk for comorbidities, and plasma interleukin 6 (IL-6) levels are among the most robust predictors of these outcomes. Tocilizumab (TCZ) blocks the receptor for IL-6, inhibiting functions of this cytokine., Methods: This was a 40-week, placebo-controlled, crossover trial (NCT02049437) where PWH on stable antiretroviral therapy (ART) were randomized to receive 3 monthly doses of TCZ or matching placebo intravenously. Following a 10-week treatment period and a 12-week washout, participants were switched to the opposite treatment. The primary endpoints were safety and posttreatment levels of C-reactive protein (CRP) and CD4+ T-cell cycling. Secondary endpoints included changes in inflammatory indices and lipid levels., Results: There were 9 treatment-related toxicities of grade 2 or greater during TCZ administration (mostly neutropenia) and 2 during placebo administration. Thirty-one of 34 participants completed the study and were included in a modified intent-to-treat analysis. TCZ reduced levels of CRP (median decrease, 1819.9 ng/mL, P < .0001; effect size, 0.87) and reduced inflammatory markers in PWH, including D-dimer, soluble CD14, and tumor necrosis factor receptors. T-cell cycling tended to decrease in all maturation subsets after TCZ administration, but was only significant among naive CD4 T cells. Lipid levels, including lipid classes that have been related to cardiovascular disease risk, increased during TCZ treatment., Conclusions: TCZ is safe and decreases inflammation in PWH; IL-6 is a key driver of the inflammatory environment that predicts morbidity and mortality in ART-treated PWH. The clinical significance of lipid elevations during TCZ treatment requires further study. Clinical Trials Registration. NCT02049437., Competing Interests: Potential conflicts of interest. N. T. F. reports grants or contracts from the NIH and Gilead, and has served as a consultant for Gilead. C. T. L. has received research grants from Gilead Sciences and Medtronic Foundation and has served on an advisory board for Esperion Therapeutics. A. L. has served as a consultant to Abbott. G. A. M. reports grants or contracts from Pfizer, Astellas, Roche, Genentech, Redhill, Cognivue, Vanda, and Tetraphase; served as scientific advisor and consultant for Gilead, Merck, Janssen, Theratechnologies, and GSK/ViiV; and received payment for expert testimony from Gilead. M. M. L. has received competitive grant funding from Gilead and has served as consultant for Merck. C. F. reports serving as a paid consultant for Gilead, Janssen, Merck, American Gene Technologies, Thera Technologies, Shinogi, and ViiV Healthcare; payment or honoraria for speaking engagements from International AIDS Society–USA and Virology Education; payment for expert testimony from Gilead Sciences; 3 issued or pending patents related to long-acting delivery of antiretroviral drugs; and participation on the scientific advisory board for Navigen Corporation and data and safety monitoring board (DSMB) or advisory board for Watermark, LLC. L. H. C. reports consulting fees from Sanofi Genzyme, Genetech, GSK, BMS, Galvani, and UCB; payment or honoraria for nonbranded speaking engagements from Sanofi and AstraZeneca. E. V. C. reports participation on a Melinta Pharmaceuticals data and safety monitoring board for a pediatric antibacterial study. D. D. A. reports a grant from the Department of Defense (grant number 12935153). C. L. S. reports a VA Merit Award and VA Career Development Award. B. R. has received payment or honoraria from Gilead Sciences, ViiV Healthcare, and Theratechnologies (paid to author). All other authors report no potential conflicts. All authors have submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Conflicts that the editors consider relevant to the content of the manuscript have been disclosed., (© The Author(s) 2023. Published by Oxford University Press on behalf of Infectious Diseases Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)
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- 2023
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4. Rapidly starting antiretroviral therapy to improve outcomes among disadvantaged groups.
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Ford N, Crawford KW, and Ameyan W
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- Antiretroviral Therapy, Highly Active, Humans, Vulnerable Populations, Anti-HIV Agents therapeutic use, HIV Infections drug therapy
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- 2021
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5. Anal neoplasia: prevention or treatment?
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Crawford KW and Nathan M
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- Humans, Anus Neoplasms prevention & control, Carcinoma in Situ, HIV Infections drug therapy, HIV Infections prevention & control
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- 2021
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6. Eliminating perinatal HIV in the United States: mission possible?
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Gnanashanmugam D, Rakhmanina N, Crawford KW, Nesheim S, Ruel T, Birkhead GS, Chakraborty R, Lawrence R, Jean-Philippe P, Jayashankar L, Hoover A, Statton A, DʼSouza P, Fitzgibbon J, Hazra R, Warren B, Smith S, and Abrams EJ
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- Communicable Disease Control organization & administration, Humans, United States, Communicable Disease Control methods, HIV Infections prevention & control, Infectious Disease Transmission, Vertical prevention & control
- Abstract
: In 2015, only 53 infants born in the United States acquired HIV - the lowest recorded number of perinatal HIV infections. Recognizing this significant achievement, we must acknowledge that the United States has not yet reached the goal of eliminating perinatal HIV transmission. This analysis describes different approaches to perinatal HIV preventive services among five states and the District of Columbia as case studies. Continuous focus on improving identification, surveillance and prevention of HIV infection in pregnant women and their infants is necessary to reach the goal of eliminating perinatal HIV transmission in the United States.
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- 2019
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7. Global HIV Antiretroviral Drug Resistance: A Perspective and Report of a National Institute of Allergy and Infectious Diseases Consultation.
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Godfrey C, Thigpen MC, Crawford KW, Jean-Phillippe P, Pillay D, Persaud D, Kuritzkes DR, Wainberg M, Raizes E, and Fitzgibbon J
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- Anti-HIV Agents therapeutic use, Antiretroviral Therapy, Highly Active, Global Health, HIV Infections drug therapy, Humans, National Institute of Allergy and Infectious Diseases (U.S.), Public Health Surveillance, Referral and Consultation, Research, United States, Anti-HIV Agents pharmacology, Drug Resistance, Viral, HIV drug effects, HIV Infections epidemiology, HIV Infections virology
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- 2017
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8. HIV birth testing and linkage to care for HIV-infected infants.
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Jean-Philippe P, Spiegel H, Gnanashanmugam D, Fitzgibbon J, DʼSouza P, Crawford KW, Jayashankar L, Bacon MC, Essajee SM, Aldrovandi GM, Cotton M, and Abrams EJ
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- Health Policy, Health Services Administration, Humans, Infant, Infant, Newborn, National Institute of Allergy and Infectious Diseases (U.S.), Point-of-Care Testing, United Nations, United States, Early Diagnosis, HIV Infections diagnosis, Mass Screening methods, Postnatal Care methods
- Abstract
: On 5-6 May 2016, the division of AIDS of the National Institute of Allergy and Infectious Diseases convened a workshop on 'HIV Birth Testing and Linkage to Care for HIV Infected Infants.' The goal of the workshop was to evaluate birth testing for early infant diagnosis (EID) of HIV, delineate technological resources for advancing a point-of-care (POC) HIV test implementable at birth and chart out the implementation hurdles for initiating early antiretroviral therapy to HIV-infected infants diagnosed at birth. The workshop addressed research and regulatory needs involved in the optimization of POC EID testing and challenges associated with implementation of EID, focusing on testing at birth. Scientific gaps and areas of intervention to accelerate and scale-up EID initiatives and birth testing were identified. These include discussion of the evidence supporting an early mortality peak among HIV-infected infant and justifying a role for birth HIV testing, including POC testing; evaluation of the current POC EID technology pipeline and test performance characteristics required for effective programmatic uptake; mathematical modeling of different testing scenarios and solutions with inclusion of birth testing; the adoption of setting-specific EID testing algorithms to achieve efficient linkage to care including early antiretroviral therapy initiation; the development of appropriate quality assurance programs to ensure accuracy of test results and enable sustainability of the testing program. Addressing these gaps and answering these challenges will be important in helping improve outcomes for HIV-infected infants and accelerate achieving the Joint United Nations Program for HIV and AIDS 90-90-90 targets in children.
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- 2017
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9. Etravirine and rilpivirine-specific mutations selected by efavirenz and nevirapine exposure in patients infected with HIV-1 non-B subtypes.
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Crawford KW
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- Alkynes, Anti-HIV Agents pharmacology, Cyclopropanes, Genotype, HIV Infections virology, HIV Reverse Transcriptase genetics, HIV-1 classification, HIV-1 enzymology, HIV-1 isolation & purification, Humans, Nitriles pharmacology, Pyridazines pharmacology, Pyrimidines pharmacology, Rilpivirine, Treatment Outcome, Viral Load, Anti-HIV Agents therapeutic use, Benzoxazines therapeutic use, Drug Resistance, Viral, HIV Infections drug therapy, HIV-1 genetics, Mutation, Missense, Nevirapine therapeutic use
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- 2014
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10. Short communication: east meets west: a description of HIV-1 drug resistance mutation patterns of patients failing first line therapy in PEPFAR clinics from Uganda and Nigeria.
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Crawford KW, Wakabi S, Kibuuka H, Magala F, Keshinro B, Okoye I, Akintunde E, and Hamm TE
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- Anti-Retroviral Agents pharmacology, Cross-Sectional Studies, Genotyping Techniques methods, HIV-1 genetics, HIV-1 isolation & purification, Humans, Nigeria, Treatment Failure, Uganda, Viral Load, Anti-Retroviral Agents therapeutic use, Drug Resistance, Viral, HIV Infections drug therapy, HIV Infections virology, HIV-1 drug effects, Mutation, Missense, Viral Proteins genetics
- Abstract
HIV-1 viral load (VL) monitoring is recommended but seldom performed in resource-constrained countries. An evaluation of patients receiving first-line antiretroviral therapy in a multicountry PEPFAR program (RV288) was performed to determine the rates and predictors of virologic suppression. Resistance data from treatment failures are available from Uganda and Nigeria. Each country enrolled 325 subjects into this cross-sectional study. Subjects on first-line therapy were randomly selected for HIV RNA testing (viral load). Regimens included efavirenz or nevirapine with zidovudine/lamivudine or tenofovir/lamivudine. VL was determined from plasma using the Roche COBAS TaqMan HIV-1 Test, High Pure System v1.0 (47 copies/ml). Genotypic resistance testing was performed on samples with VL>1,000 copies/ml. From Uganda, 85% of subjects were undetectable while 7% (23/325) had VL>1,000 copies/ml. The HIV-1 subtype distribution was as follows: A=47.6%, C=14.3%, and D=38.1%. No resistance mutations were found in 14% of subjects. All subjects with resistance had the M184V mutation. Of subjects failing a zidovudine regimen less than 1 year, 88% (7/8) had no thymidine analogue mutations (TAMs), compared to 50% (4/8) failing greater than 1 year. Four subjects (25%) had more than two mutations from the TAM-1 pathway (41L, 210W, 215Y). In Nigeria, 82% were undetectable while 14% (45/325) had VL>1,000 copies/ml. HIV-1 subtype distribution was as follows: 62.8%=CRF02_AG, 34%=pure G, and 2.8%=A. Of the 35 genotyped subjects, 14% (5/35) had no resistance mutations. Of the remainder, 10% (3/30) had no nucleoside analogue mutations while 33% (10/30) had only M184V along with nonnucleoside reverse transcriptase inhibitor (NNRTI) mutations. Forty percent (10/25) of subjects on zidovudine failed without TAMs. Another 25% (5/25) of subjects failing on zidovudine had more than two TAM-1 mutations. Individuals failing first-line antiretroviral therapy (ART) may retain sensitivity to one or more nucleoside analogues from the regimen. Knowledge of drug resistance patterns allow for selection of drugs that can be recycled in future regimens. Accumulation of resistance mutations may compromise future treatment options.
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- 2014
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11. Occurrence of etravirine/rilpivirine-specific resistance mutations selected by efavirenz and nevirapine in Kenyan patients with non-B HIV-1 subtypes failing antiretroviral therapy.
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Crawford KW, Njeru D, Maswai J, Omondi M, Apollo D, Kimetto J, Gitonga L, Munyao J, Langat R, Aoko A, Tarus J, Khamadi S, and Hamm TE
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- Cross-Sectional Studies, HIV Infections drug therapy, HIV-1 isolation & purification, Humans, Kenya, Molecular Sequence Data, Selection, Genetic, Sequence Analysis, DNA, Treatment Failure, Anti-HIV Agents pharmacology, Drug Resistance, Viral, HIV Infections virology, HIV-1 drug effects, HIV-1 genetics, Mutation, Missense
- Abstract
Resistance to efavirenz and nevirapine has not been associated with mutations at position 138 of reverse transcriptase. In an evaluation of virologic suppression rates in PEPFAR (President's Emergency Plan For AIDS Relief) clinics in Kenya among patients on first-line therapy (RV288), 63% (617/975) of randomly selected patients on antiretroviral therapy were suppressed (HIV RNA<400 copies/ml). Among those with non-nucleoside reverse transcriptase inhibitor resistance (n = 101), 14 (13.8%) had substitutions at 138 (A, G, K or Q), mutations selected only by etravirine and rilpivirine in subtype B viruses. All 14 patients received efavirenz or nevirapine, not etravirine or rilpivirine, and were predominantly subtype A1. This may be the first report of efavirenz and nevirapine selecting these mutations in these subtypes.
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- 2014
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12. Lipodystrophy and inflammation predict later grip strength in HIV-infected men: the MACS Body Composition substudy.
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Crawford KW, Li X, Xu X, Abraham AG, Dobs AS, Margolick JB, Palella FJ, Kingsley LA, Witt MD, and Brown TT
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- Absorptiometry, Photon, Adipose Tissue metabolism, Adult, Biomarkers blood, Body Composition, C-Reactive Protein analysis, HIV Infections blood, HIV Infections complications, Humans, Inflammation complications, Insulin Resistance, Interleukin-6 blood, Lipodystrophy complications, Male, Middle Aged, Receptors, Tumor Necrosis Factor blood, Tomography, X-Ray Computed, HIV Infections physiopathology, Hand Strength, Inflammation blood, Lipodystrophy blood
- Abstract
Body fat changes in HIV-infected persons are associated with increased systemic inflammation and increased mortality. It is unknown whether lipodystrophy is also associated with declines in physical function. Between 2001 and 2003, 33 HIV-infected men with evidence of lipodystrophy (LIPO⁺), 23 HIV-infected men without lipodystrophy (LIPO⁻), and 33 seronegative men were recruited from the Multicenter AIDS Cohort Study (MACS) for the Body Composition substudy. Visceral adipose tissue (VAT) was assessed by quantitative computed tomography. Lean body mass (LBM) and extremity fat were measured by dual-energy x-ray absorptiometry. Insulin resistance was estimated by Homeostatic Model Assessment (HOMA). Serum interleukin (IL)-6, soluble tumor necrosis factor (TNF)-α receptors I and II (sTNFRI and sTNFRII), and highly sensitive C-reactive protein (hs-CRP) concentrations were quantified from archived serum samples. These measurements were correlated with grip strength measured in 2007 using linear regression. At the substudy visit, the LIPO⁺ group had higher HOMA, sTNFRI, sTNFRII, and IL-6 levels than the LIPO⁻ group. In 2007, the LIPO⁺ group had lower median grip strength than the LIPO⁻ group (34.4 vs. 42.7 kg, p=0.002). Multivariable analysis of HIV⁺ men showed older age, lower LBM, higher sTNFRII concentrations, and LIPO⁺ status [adjusted mean difference -4.9 kg (p=0.045)] at the substudy visit were independently associated with lower subsequent grip strength. Inflammation, lower LBM, and lipodystrophy in HIV-infected men were associated with lower subsequent grip strength. These findings suggest that inflammation may contribute to declines in functional performance, independent of age.
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- 2013
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13. Optimising the manufacture, formulation, and dose of antiretroviral drugs for more cost-efficient delivery in resource-limited settings: a consensus statement.
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Crawford KW, Ripin DH, Levin AD, Campbell JR, and Flexner C
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- Anti-HIV Agents chemical synthesis, Anti-HIV Agents supply & distribution, Chemistry, Pharmaceutical, HIV Infections economics, HIV Infections prevention & control, Humans, Anti-HIV Agents economics, Anti-HIV Agents pharmacology, Developing Countries economics, HIV Infections drug therapy
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It is expected that funding limitations for worldwide HIV treatment and prevention in resource-limited settings will continue, and, because the need for treatment scale-up is urgent, the emphasis on value for money has become an increasing priority. The Conference on Antiretroviral Drug Optimization--a collaborative project between the Clinton Health Access Initiative, the Johns Hopkins University School of Medicine, and the Bill & Melinda Gates Foundation--brought together process chemists, clinical pharmacologists, pharmaceutical scientists, physicians, pharmacists, and regulatory specialists to explore strategies for the reduction of antiretroviral drug costs. The antiretroviral drugs discussed were prioritised for consideration on the basis of their market impact, and the objectives of the conference were framed as discussion questions generated to guide scientific assessment of potential strategies. These strategies included modifications to the synthesis of the active pharmaceutical ingredient (API) and use of cheaper sources of raw materials in synthesis of these ingredients. Innovations in product formulation could improve bioavailability thus needing less API. For several antiretroviral drugs, studies show efficacy is maintained at doses below the approved dose (eg, efavirenz, lopinavir plus ritonavir, atazanavir, and darunavir). Optimising pharmacoenhancement and extending shelf life are additional strategies. The conference highlighted a range of interventions; optimum cost savings could be achieved through combining approaches., (Copyright © 2012 Elsevier Ltd. All rights reserved.)
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- 2012
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14. Age-related changes in plasma concentrations of the HIV protease inhibitor lopinavir.
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Crawford KW, Spritzler J, Kalayjian RC, Parsons T, Landay A, Pollard R, Stocker V, Lederman MM, and Flexner C
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- Adolescent, Adult, Age Factors, Aged, Anti-HIV Agents administration & dosage, Anti-HIV Agents adverse effects, Antiretroviral Therapy, Highly Active methods, Female, HIV Infections drug therapy, HIV Protease Inhibitors administration & dosage, HIV Protease Inhibitors adverse effects, Humans, Lopinavir, Male, Middle Aged, Pyrimidinones administration & dosage, Pyrimidinones adverse effects, Young Adult, Anti-HIV Agents pharmacokinetics, HIV Protease Inhibitors pharmacokinetics, Plasma chemistry, Pyrimidinones pharmacokinetics
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The advent of highly active antiretroviral therapy in the treatment of HIV disease has substantially extended the lifespan of individuals infected with HIV resulting in a growing population of older HIV-infected individuals. The efficacy and safety of antiretroviral agents in the population are important concerns. There have been relatively few studies assessing antiretroviral pharmacokinetics in older patients. Thirty-seven subjects aged 18-30 years and 40 subjects aged 45-79 years, naive to antiretroviral therapy, received lopinavir/ritonavir (400/100) bid, emtricitibine 200 mg qd, and stavudine 40 mg bid. Trough lopinavir concentrations were available for 44 subjects, collected at 24, 36, and 96 weeks. At week 24, older age was associated with higher lopinavir trough concentrations, and a trend was observed toward older age being associated with higher lopinavir trough concentrations when all time points were evaluated. In the young cohort, among subjects with two or more measurements, there was a trend toward increasing intrasubject trough lopinavir concentrations over time. Using a nonlinear, mixed-effects population pharmacokinetic model, age was negatively associated with lopinavir clearance after adjusting for adherence. Adherence was assessed by patient self-reports; older patients missed fewer doses than younger patients (p = 0.02). No difference in grade 3-4 toxicities was observed between the two age group. Older patients have higher trough lopinavir concentrations and likely decreased lopinavir clearance. Age-related changes in the pharmacokinetics of antiretroviral drugs may be of increasing importance as the HIV-infected population ages and as older individuals comprise an increasing proportion of new diagnoses.
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- 2010
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15. Pharmacokinetic/pharmacodynamic modeling of the antiretroviral activity of the CCR5 antagonist Vicriviroc in treatment experienced HIV-infected subjects (ACTG protocol 5211).
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Crawford KW, Li C, Keung A, Su Z, Hughes MD, Greaves W, Kuritzkes D, Gulick R, and Flexner C
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- Adolescent, Adult, Aged, Anti-HIV Agents blood, Anti-HIV Agents pharmacokinetics, Anti-HIV Agents therapeutic use, Area Under Curve, Double-Blind Method, Female, HIV Infections blood, HIV Infections immunology, HIV Infections virology, Humans, Male, Middle Aged, Nonlinear Dynamics, Piperazines blood, Piperazines pharmacokinetics, Piperazines therapeutic use, Pyrimidines blood, Pyrimidines pharmacokinetics, Pyrimidines therapeutic use, RNA, Viral blood, Young Adult, Anti-HIV Agents pharmacology, CCR5 Receptor Antagonists, HIV immunology, HIV Infections drug therapy, Piperazines pharmacology, Pyrimidines pharmacology
- Abstract
Objective: This substudy of AIDS Clinical Trials Group (ACTG) Protocol 5211 explored the relationship between antiretroviral effect and plasma concentrations of vicriviroc, an investigational CCR5 antagonist for HIV infection., Methods: Eighty-six treatment-experienced subjects failing their current antiretroviral regimens were randomized to add vicriviroc 5, 10, or 15 mg once daily or placebo for 2 weeks. Beyond week 2, subjects were changed to optimized background antiretroviral treatment while continuing vicriviroc or placebo. Plasma samples collected at weeks 2 and 8 were assayed for vicriviroc concentrations and combined with vicriviroc concentration data from 110 seronegatives enrolled in 5 phase 1 studies. An inhibitory Emax model was used to assess pharmacokinetic (PK)/pharmacodynamic relationships and recursive partitioning was applied to determine the breakpoint in vicriviroc PK parameters associated with virologic suppression., Results: A 2-compartment model was fitted to the drug concentration data. At week 2, a higher vicriviroc Cmin was associated with a greater mean drop in HIV RNA (viral load) and a higher percentage of subjects experiencing a >1 log10 copies/mL drop in viral load. In subjects with Cmin > 54 ng/mL, the mean viral load decrease was 1.35 log10 copies/mL vs. 0.76 log10 with Cmin < 54 ng/mL (P = 0.003, Student t test). At this Cmin breakpoint, 70% of subjects with the higher Cmin had a >1 log drop in HIV RNA, compared with 44% with a lower Cmin (P = 0.048, Fisher exact test). Similar results were seen with an area under the curve breakpoint of 1460 ng h/mL. At weeks 16 and 24, all vicriviroc-treated subjects experienced better viral load responses than placebo recipients, but there was no apparent relationship between PK and change in viral load among these vicriviroc-treated subjects., Conclusions: There was a positive correlation between vicriviroc Cmin, area under the curve, and viral load changes at week 2 in treatment-experienced HIV-infected subjects receiving no other new active antiretroviral drugs. This correlation did not persist beyond week 16, probably because treatment response at that point also depended on having other active drugs in the regimen.
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- 2010
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16. Novel ceramide analogues display selective cytotoxicity in drug-resistant breast tumor cell lines compared to normal breast epithelial cells.
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Crawford KW, Bittman R, Chun J, Byun HS, and Bowen WD
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- Apoptosis physiology, Cell Line, Tumor, Ceramides chemistry, Epithelial Cells metabolism, Female, Humans, L-Lactate Dehydrogenase metabolism, Antineoplastic Agents pharmacology, Breast Neoplasms drug therapy, Ceramides pharmacology, Drug Resistance, Neoplasm physiology, Epithelial Cells drug effects
- Abstract
The sphingolipid ceramide is involved in diverse cell signaling pathways related to proliferation and differentiation. Elevated ceramide also triggers apoptosis. Synthetic ceramide derivatives have been shown to be cytotoxic to tumors, yet few studies have evaluated whether cytotoxicity of synthetic ceramides is selective for tumor cells. We have evaluated the cytotoxic potency of several novel ceramide analogues in the drug-resistant breast tumor cell lines, SKBr3 and MCF-7/Adr, and compared their cytotoxicity in normal breast epithelial cells. Cytotoxicity was assessed using release of lactate dehydrogenase into the culture medium. (2S, 3S)-3-(6'-Dodecylpyridin-2'-yl)-2-butanoylamidopropane-1,3-diol (pyridine-C4-ceramide) produced non-selective cytotoxicity across the three cell types (EC50= 12.8-16.7 microM, at 24 hr). However, 2S,5R-2-(octanoylamido-(3E))-octadecene-1,5-diol (5R-OH-3E-C8-ceramide), (2S,3R)-2-(N-adamantoyl)-(4E)-octadecen-1,3-diol (adamantyl-ceramide), and (2S,3R)-3-(3'-dodecylphenyl)-2-butanoylamidopropane-1,3-diol (benzene-C4-ceramide) exhibited increased cytotoxicity in the tumor cell lines compared to the normal breast epithelial cells. The EC50 values (microM) at 24 hr for these compounds in SKBr3 cells, MCF-7/Adr cells, and normal breast epithelial cells, respectively, were as follows: 5R-OH-3E-C8-ceramide, 18.3, 21.2 and 58.7; adamantyl-ceramide, 10.9, 24.9 and >100; benzene-C4-ceramide, 18.9, 45.5 and >100. At a concentration of 30 microM, the fold increase in cytotoxicity in breast tumor cell lines compared with normal breast epithelial cells was as follows: 5R-OH-3E-C8-ceramide, 23.7 and 19; adamantyl-ceramide, 11.2 and 10.3 and benzene-C4-ceramide, 79.3 and 77.2, for SKBr3 and MCF-7/Adr cells, respectively. Possible mechanisms accounting for selectivity are discussed. Ceramide analogues with relatively selective toxicity against tumor cells may have potential as therapeutic agents. Elucidating the mechanisms of selective cytotoxicity could identify novel targets that may lead to development of anti-neoplastic agents with a higher therapeutic index.
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- 2003
17. sigma(2) Receptors regulate changes in sphingolipid levels in breast tumor cells.
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Crawford KW, Coop A, and Bowen WD
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- Benzylidene Compounds pharmacology, Breast Neoplasms, Cell Division, Cyclohexylamines pharmacology, Humans, Infant, Morphinans pharmacology, Oxalates pharmacology, Piperidines pharmacology, Pyrrolidines pharmacology, Receptors, sigma agonists, Tumor Cells, Cultured, Receptors, sigma physiology, Sphingomyelins metabolism
- Abstract
sigma(2) Receptors induce apoptosis in various cell types. The sphingolipid, ceramide as well as the sphingoid bases are involved in cell proliferation. Sphingolipids of MCF-7/Adr- and T47D breast tumor cells were metabolically radiolabeled. The sigma(2) receptor agonists (+)-1R,5R-E-8-(3,4-dichlorobenzylidene)-5-(3-hydroxyphenyl)-2-methylmorphan-7-one (CB-184) and 1S,2R-(--)-cis-N-[2-(3,4-dichlorophenyl)ethyl]-N-methyl-2-(1-pyrrolidinyl)-cyclohexylamine (BD737) caused dose-dependent increases in [(3)H]ceramide, with concomitant decreases in [(3)H]sphingomyelin. Both effects were attenuated by the novel sigma(2) receptor antagonist, N-phenethylpiperidine oxalate (AC927). sigma(2) Receptors may produce effects on cell growth and apoptosis by regulating the sphingolipid pathway.
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- 2002
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18. Sigma-2 receptor agonists activate a novel apoptotic pathway and potentiate antineoplastic drugs in breast tumor cell lines.
- Author
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Crawford KW and Bowen WD
- Subjects
- Apoptosis physiology, Benzylidene Compounds pharmacology, Breast Neoplasms pathology, Caspases physiology, Cyclophosphamide pharmacology, DNA Damage physiology, Dactinomycin pharmacology, Drug Synergism, Haloperidol pharmacology, Humans, Ligands, Morphinans pharmacology, Tumor Cells, Cultured, Tumor Suppressor Protein p53 genetics, Tumor Suppressor Protein p53 physiology, Antineoplastic Agents pharmacology, Apoptosis drug effects, Breast Neoplasms drug therapy, Receptors, sigma agonists
- Abstract
We have reported previously that sigma-2 receptors are expressed in high densities in a variety of tumor cell types (B. J. Vilner et al., Cancer Res., 55: 408-413, 1995) and that various sigma ligands have cytotoxic effects (B. J. Vilner et al., J. Neurosci., 15: 117-134, 1995). Other investigators have demonstrated increased expression of sigma-2 receptors in rapidly proliferating tumors (R. H. Mach et al., Cancer Res., 57: 156-161, 1997) and the ability of some sigma ligands to inhibit proliferation (P. J. Brent and G. T. Pang, Eur. J. Pharmacol., 278: 151-160, 1995). We demonstrate here the ability of sigma-2 receptor agonists to induce cell death by a mechanism consistent with apoptosis. In breast tumor cell lines that are sensitive (MCF-7) and resistant (MCF-7/Adr-, T47D, and SKBr3) to antineoplastic agents, incubation with the sigma-2 subtype-selective agonists CB-64D and CB-184 produced dose-dependent cytotoxicity (measured by lactate dehydrogenase release into medium). The EC(50) for this response was similar across cell lines, irrespective of p53 genotype and drug-resistance phenotype. CB-64D and the subtype nonselective sigma-2 agonists haloperidol and reduced haloperidol induced terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling staining in MCF-7 and T47D cells, indicating that cell death occurs via apoptosis. Apoptosis was also indicated by increases in Annexin V binding caused by CB-64D. In MCF-7 cells, cytotoxicity and Annexin V binding induced by the antineoplastics doxorubicin and actinomycin D was partially or completely abrogated by certain specific and general inhibitors of caspases. In contrast, caspase inhibitors had no effect on sigma-2 receptor-mediated (CB-64D and CB-184) cytotoxicity or Annexin V binding. Marked potentiation of cytotoxicity was observed when a subtoxic dose of CB-184 was combined with doxorubicin or actinomycin D, both in drug-sensitive (MCF-7) and drug-resistant (MCF-7/Adr-) cell lines. Haloperidol potentiated doxorubicin only in drug-resistant cells. These findings suggest the involvement of a novel p53- and caspase-independent apoptotic pathway used by sigma-2 receptors, which is distinct from mechanisms used by some DNA-damaging, antineoplastic agents and other apoptotic stimuli. These observations further suggest that sigma-2 receptors may be targets that can be therapeutically exploited in the treatment of both drug-sensitive and drug-resistant metastatic tumors.
- Published
- 2002
19. Patient-interactive computer system for obtaining medication histories.
- Author
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DeLeo JM, Pucino F, Calis KA, Crawford KW, Dorworth T, and Gallelli JF
- Subjects
- Adult, Aged, Drug Information Services, Female, Humans, Interviews as Topic, Male, Middle Aged, Clinical Pharmacy Information Systems, Medical History Taking methods, Medical Records Systems, Computerized
- Abstract
A portable, patient-interactive computerized system for obtaining medication histories is described. A comprehensive interview script modeling pharmacist-conducted medication-history interviews was written in lay language. The script contains sections on demographics, current medical conditions, medication regimen, medication compliance, symptoms, allergy history, dietary history, psychosocial history, and occupational and environmental exposure; it also asks the patient to evaluate the system. Some of the information requested is often not obtained by physicians during the history and physical examination. A program that conducts the interview by processing a computerized version of the script was developed with Microsoft QuickBASIC. The program was designed to be run on a personal computer microprocessor so that an interview can be conducted virtually anywhere by using a desktop or laptop computer. Summary reports suitable for inclusion in the medical record are generated after each interview. Patients using the system took an average of 40 minutes to complete an interview. They entered data easily and accurately, and they gave the system a high overall rating. The medication-history interviewing system described produces useful, comprehensive, and consistent reports and requires about the same amount of time to conduct an interview as a human interviewer.
- Published
- 1993
20. Angiotensin II receptor recognized by DuP753 regulates two distinct guanine nucleotide-binding protein signaling pathways.
- Author
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Crawford KW, Frey EA, and Cote TE
- Subjects
- Adenylate Cyclase Toxin, Adenylyl Cyclase Inhibitors, Angiotensin II antagonists & inhibitors, Angiotensin II pharmacology, Angiotensin Receptor Antagonists, Animals, Cell Membrane metabolism, Guanosine Triphosphate physiology, Losartan, Pertussis Toxin, Phosphatidylinositols metabolism, Pituitary Gland, Anterior pathology, Pituitary Neoplasms enzymology, Pituitary Neoplasms pathology, Rats, Rats, Inbred BUF, Sulfhydryl Reagents pharmacology, Tritium, Tumor Cells, Cultured drug effects, Type C Phospholipases drug effects, Type C Phospholipases metabolism, Virulence Factors, Bordetella pharmacology, Angiotensin II metabolism, Biphenyl Compounds pharmacology, GTP-Binding Proteins physiology, Imidazoles pharmacology, Receptors, Angiotensin physiology, Signal Transduction physiology, Tetrazoles pharmacology
- Abstract
The 7315c cell, derived from a rat anterior pituitary tumor, expresses an angiotensin II (AII) receptor. [3H]AII binds to 7315c membranes specifically and saturably (Kd = 2.1 +/- 0.6 x 10(-6) M, Bmax = 282 +/- 33 fmol/mg of protein). GTP diminished the affinity of the membranes for [3H]AII (Kd = 4.1 +/- 0.4 x 10(-9) M, Bmax = 210 +/- 26 fmol/mg of protein). [3H]AII binding was displaced by AII (Ki = 1.3 +/- 0.6 x 10(-9) M), angiotensin III (AIII) (Ki = 0.9 +/- 0.4 x 10(-9) M), and the nonpeptide AII antagonist DuP753 (Ki = 1.4 +/- 0.6 x 10(-8) M). In contrast, a second nonpeptide AII ligand, PD123177, did not compete for [3H]AII binding sites. In intact cells, AII and AIII stimulated inositol trisphosphate (IP3) production (EC50 = 1.1 +/- 0.6 x 10(-8) M and 1.1 +/- 0.5 x 10(-8) M, respectively); this response to AII was antagonized by DuP753 (Ki = 1.7 +/- 0.3 x 10(-7) M). Pertussis toxin treatment failed to affect the ability of AII to stimulate IP3 production. In a crude membrane preparation, GTP was required for maximal AII-induced IP3 stimulation; guanosine thio-diphosphate abolished the agonist-GTP stimulation of IP3 production, in a concentration-dependent fashion. AII and AIII also inhibited adenylyl cyclase (EC50 = 2.9 +/- 1.1 x 10(-8) M and 6.0 +/- 1.0 x 10(-8) M, respectively). DuP753 antagonized the inhibition by AII of adenylyl cyclase (Ki = 2.8 +/- 0.4 x 10(-8) M). PD123177 failed to antagonize AII-induced cyclase inhibition. Pertussis toxin treatment abolished the AII and AIII inhibition of adenylyl cyclase. GTP was required for AII-induced inhibition of adenylyl cyclase. These data suggest that, in 7315c cells, a single subtype of AII receptor, identified by DuP753, is capable of regulating two different guanine nucleotide-binding protein (G protein) signalling pathways; one G protein, which is insensitive to pertussis toxin, stimulates IP3 production and the other G protein, which is sensitive to pertussis toxin, inhibits adenylyl cyclase.
- Published
- 1992
21. Treatment of suspected postcholecystectomy diarrhea with psyllium hydrophilic mucilloid.
- Author
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Strommen GL, Dorworth TE, Walker PR, Crawford KW, and Pucino F
- Subjects
- Aged, Diarrhea etiology, Humans, Male, Cholecystectomy, Diarrhea drug therapy, Postoperative Complications drug therapy, Psyllium therapeutic use
- Published
- 1990
22. The identification of lysergic acid amide in baby Hawaiian woodrose by mass spectrometry.
- Author
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Crawford KW
- Subjects
- Amides isolation & purification, Chemical Phenomena, Chemistry, Chromatography, Thin Layer, Infrared Rays, Seeds analysis, Spectrophotometry, Ergolines isolation & purification, Plants analysis
- Published
- 1970
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