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214 result(s) for "Winters, Mark"
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Oral prenylation inhibition with lonafarnib in chronic hepatitis D infection: a proof-of-concept randomised, double-blind, placebo-controlled phase 2A trial
Therapies for chronic hepatitis delta virus (HDV) infection are unsatisfactory. Prenylation is essential for HDV and inhibition abrogates HDV production in experimental models. In a proof-of-concept study, we aimed to assess the effect on HDV RNA levels, safety, and tolerability of the prenylation inhibitor lonafarnib in patients with chronic delta hepatitis. In this phase 2A double-blind, randomised, placebo-controlled study, patients aged 18 years or older with chronic HDV infection were randomly assigned (3:1 in group 1 and 2:1 in group 2) to receive lonafarnib 100 mg (group 1) or lonafarnib 200 mg (group 2) twice daily for 28 days with 6 months' follow-up. Participants were randomised by random-number tables blocked in groups of four without stratification. Both groups enrolled six treatment participants and two placebo participants. Group 1 placebo patients received open-label lonafarnib as group 2 participants. The primary therapeutic endpoint was a decrease in HDV RNA viral titre in serum and the primary safety endpoint was the ability to tolerate the drug at the prescribed dose for the full 4-week duration, defined as drug discontinuation due to intolerance or grade 3/4 adverse events. This trial is registered with ClinicalTrials.gov, number NCT01495585. Between Jan 19, 2012, and April 28, 2014, 14 patients were enrolled, of whom eight were assigned to group 1 and six were assigned to group 2. At day 28, compared with placebo, mean log HDV RNA declines from baseline were −0·73 log IU/mL in group 1 (95% CI 0·17–1·31; p=0·03) and −1·54 log IU/mL in group 2 (1·21–1·93; p<0·0001). Lonafarnib serum concentrations correlated with HDV RNA change (r2=0·78, p<0·0001). Model fits show that hepatitis B surface antigen (HBsAg) remained stable after a short pharmacological delay (0·75 days [SE 0·24]), lonafarnib effectiveness in blocking HDV production was greater in group 2 than in group 1 (0·952 [SE 0·06] vs 0·739 [0·05], p<0·001), and the HDV half-life was 1·62 days (0·07). There was no evidence of virological resistance. Adverse events were mainly mild to moderate with group 1 patients experiencing diarrhoea in three patients (50%) and nausea in two patients (33%) and in group 2 with all patients (100%) experiencing nausea, diarrhoea, abdominal bloating, and weight loss greater than 2 kg (mean of 4 kg). No treatment discontinuations occurred in any treatment groups. Treatment of chronic HDV with lonafarnib significantly reduces virus levels. The decline in virus levels significantly correlated with serum drug levels, providing further evidence for the efficacy of prenylation inhibition in chronic HDV. National Institute of Diabetes and Digestive and Kidney Diseases and National Cancer Institute, National Institutes of Health, and Eiger Biopharmaceuticals Inc.
Zika virus infection in the Veterans Health Administration (VHA), 2015-2016
Zika virus (ZIKV) is an important flavivirus infection. Although ZIKV infection is rarely fatal, risk for severe disease in adults is not well described. Our objective was to describe the spectrum of illness in U.S. Veterans with ZIKV infection. Case series study including patients with laboratory-confirmed or presumed positive ZIKV infection in all Veterans Health Administration (VHA) medical centers. Adjusted odds ratios of clinical variables associated with hospitalization and neurologic complications was performed. Of 1,538 patients tested between 12/2015-10/2016 and observed through 3/2017, 736 (48%) were RT-PCR or confirmed IgM positive; 655 (89%) were male, and 683 (93%) from VA Caribbean Healthcare System (VACHCS). Ninety-four (13%) were hospitalized, 91 (12%) in the VACHCS. Nineteen (3%) died after ZIKV infection. Hospitalization was associated with increased Charlson co-morbidity index (adjusted odds ratio [OR] 1.2; 95% confidence interval [CI], 1.1-1.3), underlying connective tissue disease (OR, 29.5; CI, 3.6-244.7), congestive heart failure (OR, 6; CI, 2-18.5), dementia (OR, 3.6; CI, 1.1-11.2), neurologic symptom presentation (OR, 3.9; CI, 1.7-9.2), leukocytosis (OR, 11.8; CI, 4.5-31), thrombocytopenia (OR, 7.8; CI, 3.3-18.6), acute kidney injury (OR, 28.9; CI, 5.8-145.1), or using glucocorticoids within 30 days of testing (OR, 13.3; CI 1.3-133). Patients presenting with rash were less likely to be hospitalized (OR, 0.29; CI, 0.13-0.66). Risk for neurologic complications increased with hospitalization (OR, 5.9; CI 2.9-12.2), cerebrovascular disease (OR 4.9; CI 1.7-14.4), and dementia (OR 2.8; CI 1.2-6.6). Older Veterans with multiple comorbidities or presenting with neurologic symptoms were at increased risk for hospitalization and neurological complications after ZIKV infection.
Chikungunya Fever Cases Identified in the Veterans Health Administration System, 2014
During December 2013, the first locally transmitted chikungunya virus (CHIKV) infections in the Americas were reported in the Caribbean. Although CHIKV infection is rarely fatal, risk for severe disease increases with age and medical comorbidities. Herein we describe characteristics of Veterans Health Administration (VHA) patients with CHIKV infection and, among those with infections diagnosed in Puerto Rico, investigated risk factors for hospitalization. We queried VHA's national electronic medical records to identify patients with CHIKV testing during 2014. Demographics, clinical history, laboratory results, and outcomes were abstracted. We investigated risk factors for hospitalization among patients with laboratory-confirmed CHIKV infection in Puerto Rico. We identified 180 laboratory-confirmed CHIKV infections; 148 (82.2%) were diagnosed in Puerto Rico, and 32 (17.8%) were diagnosed among returning travelers elsewhere in the United States. In Puerto Rico, where more patients were hospitalized (55.4% versus 20.0%) and died (4.1% versus 0%), risk for hospitalization increased with age (relative risk [RR]/each 10-year increase, 1.19; 95% confidence interval [CI], 1.06-1.32) and, adjusted for age, increased among patients with congestive heart failure (RR, 1.58; 95% CI, 1.25-1.99), chronic kidney disease (RR, 1.52; 95% CI, 1.19-1.94), diabetes mellitus (RR, 1.39; 95% CI, 1.06-1.84), or chronic lung disease (RR, 1.37; 95% CI, 1.03-1.82). CHIKV infection is an emerging problem among Veterans residing in or visiting areas with CHIKV transmission. Although overall mortality rates are low, clinicians in affected areas should be aware that older patients and patients with comorbidities may be at increased risk for severe disease.
Clusters of nontuberculous mycobacteria linked to water sources at three Veterans Affairs medical centers
To characterize nontuberculous mycobacteria (NTM) associated with case clusters at 3 medical facilities. Retrospective cohort study using molecular typing of patient and water isolates. Veterans Affairs Medical Centers (VAMCs). Isolation and identification of NTM from clinical and water samples using culture, MALDI-TOF, and gene population sequencing to determine species and genetic relatedness. Clinical data were abstracted from electronic health records. An identical strain of Mycobacterium conceptionense was isolated from 41 patients at VA Medical Centers (VAMCs A, B, and D), and from VAMC A's ICU ice machine. Isolates were initially identified as other NTM species within the M. fortuitum clade. Sequencing analyses revealed that they were identical M. conceptionense strains. Overall, 7 patients (17%) met the criteria for pulmonary or nonpulmonary infection with NTM, and 13 of 41 (32%) were treated with effective antimicrobials regardless of infection or colonization status. Separately, a M. mucogenicum patient strain from VAMC A matched a strain isolated from a VAMC B ICU ice machine. VAMC C, in a different state, had a 4-patient cluster with Mycobacterium porcinum. Strains were identical to those isolated from sink-water samples at this facility. NTM from hospital water systems are found in hospitalized patients, often during workup for other infections, making attribution of NTM infection problematic. Variable NTM identification methods and changing taxonomy create challenges for epidemiologic investigation and linkage to environmental sources.
A Transitional Endogenous Lentivirus from the Genome of a Basal Primate and Implications for Lentivirus Evolution
Lentiviruses chronically infect a broad range of mammalian species and have been transmitted from primates to humans, giving rise to multiple outbreaks of HIV infection over the past century. Although the circumstances surrounding these recent zoonoses are becoming clearer, the nature and timescale of interaction between lentiviruses and primates remains unknown. Here, we report the discovery of an endogenous lentivirus in the genome of the gray mouse lemur (Microcebus murinus), a strepsirrhine primate from Madagascar, demonstrating that lentiviruses are capable of invading the primate germ line. Phylogenetic analysis places gray mouse lemur prosimian immunodeficiency virus (pSIVgml) basal to all known primate lentiviruses and, consistent with this, its genomic organization is intermediate between the nonprimate lentiviruses and their more derived primate counterparts. Thus, pSIVgml represents the first unambiguous example of a viral transitional form, revealing the acquisition and loss of genomic features during lentiviral evolution. Furthermore, because terrestrial mammal populations in Madagascar and Africa are likely to have been isolated from one another for at least 14 million years, the presence of pSIVgml in the gray mouse lemur genome indicates that lentiviruses must have been infecting primates for at least this period of time, or have been transmitted between Malagasy and African primate populations by a vector species capable of traversing the Mozambique channel. The discovery of pSIVgml illustrates the utility of endogenous sequences for the study of contemporary retroviruses and indicates that primate lentiviruses may be considerably older and more broadly distributed than previously thought.
Development of Elvitegravir Resistance and Linkage of Integrase Inhibitor Mutations with Protease and Reverse Transcriptase Resistance Mutations
Failure of antiretroviral regimens containing elvitegravir (EVG) and raltegravir (RAL) can result in the appearance of integrase inhibitor (INI) drug-resistance mutations (DRMs). While several INI DRMs have been identified, the evolution of EVG DRMs and the linkage of these DRMs with protease inhibitor (PI) and reverse transcriptase inhibitor (RTI) DRMs have not been studied at the clonal level. We examined the development of INI DRMs in 10 patients failing EVG-containing regimens over time, and the linkage of INI DRMs with PI and RTI DRMs in these patients plus 6 RAL-treated patients. A one-step RT-nested PCR protocol was used to generate a 2.7 kB amplicon that included the PR, RT, and IN coding region, and standard cloning and sequencing techniques were used to determine DRMs in 1,277 clones (mean 21 clones per time point). Results showed all patients had multiple PI, NRTI, and/or NNRTI DRMs at baseline, but no primary INI DRM. EVG-treated patients developed from 2 to 6 strains with different primary INI DRMs as early as 2 weeks after initiation of treatment, predominantly as single mutations. The prevalence of these strains fluctuated and new strains, and/or strains with new combinations of INI DRMs, developed over time. Final failure samples (weeks 14 to 48) typically showed a dominant strain with multiple mutations or N155H alone. Single N155H or multiple mutations were also observed in RAL-treated patients at virologic failure. All patient strains showed evidence of INI DRM co-located with single or multiple PI and/or RTI DRMs on the same viral strand. Our study shows that EVG treatment can select for a number of distinct INI-resistant strains whose prevalence fluctuates over time. Continued appearance of new INI DRMs after initial INI failure suggests a potent, highly dynamic selection of INI resistant strains that is unaffected by co-location with PI and RTI DRMs.
Immune Biomarker Differences and Changes Comparing HCV Mono-Infected, HIV/HCV Co-Infected, and HCV Spontaneously Cleared Patients
Immune biomarkers are implicated in HCV treatment response, fibrosis, and accelerated pathogenesis of comorbidities, though only D-dimer and C-reactive protein have been consistently studied. Few studies have evaluated HIV/HCV co-infection, and little longitudinal data exists describing a broader antiviral cytokine response. Fifty immune biomarkers were analyzed at baseline (BL) and HCV end of treatment follow-up(FU) time point using the Luminex 50-plex assay in plasma samples from 15 HCV-cleared, 24 HCV mono- and 49 HIV/HCV co-infected patients receiving antiretroviral treatment, who either did or did not receive pegylated-interferon/ribavirin HCV treatment. Biomarker levels were compared among spontaneous clearance patients, mono- and co-infected, untreated and HCV-treated, and sustained virologic responders (SVR) and non-responders (NR) at BL and FU using nonparametric analyses. A Bonferroni correction, adjusting for tests of 50 biomarkers, was used to reduce Type I error. Compared to HCV patients at BL, HIV/HCV patients had 22 significantly higher and 4 significantly lower biomarker levels, following correction for multiple testing. There were no significantly different BL levels when comparing SVR and NR in mono- or co-infected patients; however, FU levels changed considerably in co-infected patients, with seven becoming significantly higher and eight becoming significantly lower in SVR patients. Longitudinally between BL and FU, 13 markers significantly changed in co-infected SVR patients, while none significantly changed in co-infected NR patients. There were also no significant changes in longitudinal analyses of mono-infected patients achieving SVR or mono-infected and co-infected groups deferring treatment. Clear differences exist in pattern and quantity of plasma immune biomarkers among HCV mono-infected, HIV/HCV co-infected, and HCV-cleared patients; and with SVR in co-infected patients treated for HCV. Though >90% of patients were male and co-infected had a larger percentage of African American patients, our findings may have implications for better understanding HCV pathogenesis, treatment outcomes, and future therapeutic targets.
Phase 2 gene therapy trial of an anti-HIV ribozyme in autologous CD34+ cells
The first phase 2 gene therapy trial for HIV-1 has shown some promising signs. There's a long way to go before this would be a viable approach in people with HIV—this trial did not show a statistically significant difference in viral load at the primary end point–but other analyses did reveal that the gene therapy seemed to have a modest, but statistically significant, effect at reducing viral load in the treated subjects versus the placebo arm. The study also provides some clues about what to improve in the future. Gene transfer has potential as a once-only treatment that reduces viral load, preserves the immune system and avoids lifetime highly active antiretroviral therapy. This study, which is to our knowledge the first randomized, double-blind, placebo-controlled, phase 2 cell-delivered gene transfer clinical trial, was conducted in 74 HIV-1–infected adults who received a tat - vpr –specific anti-HIV ribozyme (OZ1) or placebo delivered in autologous CD34 + hematopoietic progenitor cells. There were no OZ1-related adverse events. There was no statistically significant difference in viral load between the OZ1 and placebo group at the primary end point (average at weeks 47 and 48), but time-weighted areas under the curve from weeks 40–48 and 40–100 were significantly lower in the OZ1 group. Throughout the 100 weeks, CD4 + lymphocyte counts were higher in the OZ1 group. This study indicates that cell-delivered gene transfer is safe and biologically active in individuals with HIV and can be developed as a conventional therapeutic product.
Impact of interferon-ribavirin treatment on hepatitis C virus (HCV) protease quasispecies diversity in HIV- and HCV-coinfected patients
Patients with hepatitis C virus (HCV) and human immunodeficiency virus (HIV) coinfection for whom prior treatment of HCV with interferon-ribavirin has failed may require subsequent treatment with new HCV protease inhibitors (PIs). We evaluated the diversity of HCV nonstructural protein 3 (NS3) in 26 HCV- and HIV-coinfected patients receiving stable antiretroviral therapy (ART) who were treated with interferon-ribavirin. Plasma HCV RNA clonal analysis was performed. There was greater baseline NS3 diversity in patients with nonresponse or relapse than in those with sustained virologic response. Interferon-ribavirin treatment did not result in significant changes in HCV protease gene diversity or significant HCV PI resistance mutations. The effect of prior interferon-ribavirin treatment on HCV NS3 will likely not impact HCV PI efficacy in HIV-coinfected patients receiving ART.
Inter- and Intragenic Variations Complicate the Molecular Epidemiology of Human Cytomegalovirus
Human cytomegalovirus isolates were analyzed, both by restriction fragment–length polymorphism typing and by sequencing for intra- and intergenic variability at 9 sites on the genome, to determine whether genetic variation influenced disease outcome and whether linkage among genes could be identified. Variation at the UL55 (glycoprotein B [gB]), UL74 (gO), UL75 (gH), UL115 (gL), US9, and US28 gene open-reading frames was studied in relationship to outcome of cytomegalovirus disease. Major findings were that (1) on the basis of analysis of only 9 genomic sites, it is apparent that an almost infinite number of genetic combinations are theoretically possible; (2) genetic linkages are rare; (3) intragenic variability may be a complicating factor in molecular epidemiologic studies; and (4) analysis of only a single gene from a clinical isolate may not reveal the presence of either intragenic variants or mixtures of genotypes