Background
Direct acting anti-HCV drugs have demonstrated a high cure rate and favorable tolerability. The development of shorter courses of therapy may improve affordability and adherence. Sofosbuvir and ledipasvir together with ribavirin have yielded high efficacy when administered for 8, but not for 6 weeks. We hypothesized that addition of a third potent directly acting antiviral to sofosbuvir and ledipasvir would allow for shortened durations of therapy.
Methods
In this single center, open-label cohort, phase 2 atrial, sixty HCV GT-1 treatment naïve patients were sequentially enrolled onto three arms and treated with 12 weeks of sofosbuvir and ledipasvir (an NS5B nucleotide polymerase inhibitor and an NS5A inhibitor, respectively) (n=20); or 6 weeks with sofosbuvir, ledipasvir, and GS-9669 (a non-nucleoside NS5B inhibitor) (n=20) or 6 weeks with sofosbuvir, ledipasvir and GS-9451 (an NS3/4A protease inhibitor) (n=20). Patients and investigators were unmasked to treatment assignment. The primary efficacy analysis was SVR12 (HCV RNA less than the level of quantitation 12 weeks after treatment completion).
Findings
All subjects treated with sofosbuvir and ledipasvir for 12 weeks achieved SVR12 (95%CI: 83–100%). Nineteen of 20 patients (95% CI: 75–100%) treated with sofosbuvir, ledipasvir and GS-9669 achieved SVR12, with 1 patient relapsing 2 weeks after completion of therapy. Nineteen of 20 patients (95% CI: 75–100%) treated with sofosbuvir, ledipasvir, and GS-9451 for 6 weeks achieved SVR12, one patient was lost to follow up after achieving SVR4. There were no discontinuations of treatment due to adverse events.
Interpretation
In this small proof of concept study, two different three drug regimens administered for 6 weeks resulted in high cure rates for HCV infection with excellent tolerability.
Funding
NIAID, National Cancer Institute and Clinical Center Intramural Program. Clinical Trials.gov number NCT01805882. The study was also supported in part by the German Research Foundation (DFG) by the clinical research unit KFO 129 and a Collaborative Research and Development Agreement between NIH and Gilead Sciences.
Genetic variations in certain components of the glucocorticoid receptor (GR) chaperone complex have been associated with the development of stress-related affective disorders and individual variability in therapeutic responses to antidepressants. Mechanisms that link GR chaperoning and stress susceptibility are not well understood. Here, we show that the effects of glucocorticoid hormones on socioaffective behaviors are critically regulated via reversible acetylation of Hsp90, a key component of the GR chaperone complex. We provide pharmacological and genetic evidence indicating that the cytoplasmic lysine deacetylase HDAC6 controls Hsp90 acetylation in the brain, and thereby modulates Hsp90-GR protein-protein interactions, as well as hormone- and stress-induced GR translocation, with a critical impact on GR downstream signaling and behavior. Pet1-Cre driven deletion of HDAC6 in serotonin neurons, the densest HDAC6-expressing cell group in the mouse brain, dramatically reduced acute anxiogenic effects of the glucocorticoid hormone corticosterone in the open field, elevated plus maze, and social interaction tests. Serotonin-selective depletion of HDAC6 also blocked the expression of social avoidance in mice exposed to chronic social defeat and concurrently prevented the electrophysiological and morphological changes induced, in serotonin neurons, by this murine model of traumatic stress. Together, these results identify HDAC6 inhibition as a potential new strategy for pro-resilience and antidepressant interventions through regulation of the Hsp90-GR heterocomplex and focal prevention of GR signaling in serotonin pathways. Our data thus uncover an alternate mechanism by which pan-HDAC inhibitors may regulate stress-related behaviors independently of their action on histones.
Background
As treatment for chronic hepatitis C (HCV) virus has evolved to all-oral, interferon-free directly acting antiviral (DAA) therapy, the impact of these improvements on patient adherence has not been described.MethodsMedication
adherence was measured in 60 HCV, genotype-1, treatment-naïve participants enrolled in a phase 2a clinical trial at the National Institutes of Health and community clinics. Participants received either ledipasvir/sofosbuvir (LDV/SOF) (90 mg/400 mg) (one pill) daily for 12 weeks, LDV/SOF + GS-9451 (80 mg/day) (two pills) daily for 6 weeks, or LDV/SOF + GS-9669 (500 mg twice daily; three pills, two in the morning, one in the evening) for 6 weeks. Adherence was measured using medication event monitoring system (MEMS) caps, pill counts and patient report.ResultsOverall adherence to DAAs was high. Adherence declined over the course of the 12-week treatment (p = 0.04). While controlled psychiatric disease or symptoms of depression did not influence adherence, recent drug use was a risk factor for non-adherence to 12-week (p = 0.01), but not 6-week regimens. Adherence as measured by MEMS was lower than by patient report.ConclusionsAdherence to short courses of DAA therapy with 1–3 pills a day was excellent in an urban population with multiple risk factors for non-adherence.Electronic supplementary materialThe online version of this article (doi:10.1007/s12072-015-9680-7) contains supplementary material, which is available to authorized users.
RBV-MP concentrations in RBC at day 14 were related to anaemia and SVR. A therapeutic range was identified for RBV-MP in persons with HCV GT1 disease receiving 24 weeks of sofosbuvir plus ribavirin, suggesting a potential pharmacological basis for individualized ribavirin dosing in IFN-free regimens.
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