Comparison of phenotypic and genotypic tropism determination in triple-class-experienced HIV patients eligible for maraviroc treatment

BACKGROUND: Determination of HIV-1 tropism is a pre-requisite to the use of CCR5 antagonists. This study evaluated the potential of population genotypic tropism tests (GTTs) in clinical practice, and the correlation with phenotypic tropism tests (PTTs) in patients accessing routine HIV care. METHODS: Forty-nine consecutive plasma samples for which an original Trofile(TM) assay was performed were obtained from triple-class-experienced patients in need of a therapy change. Viral tropism was defined as the consensus of three or more tropism calls obtained from the combination of two independent population PTT assays (Trofile Biosciences, San Francisco, CA, USA, and Virco, Beerse, Belgium), population GTTs and GTTs based on ultra-deep sequencing. If no consensus was reached, a clonal PTT was performed in order to finalize the tropism call. This two-step approach allowed the definition of a reference tropism call. RESULTS: According to the reference tropism result, 35/49 samples were CCR5 tropic (R5) (patients eligible for maraviroc treatment) and 14/49 were assigned as non-R5 tropic. The non-R5 samples [patients not eligible for maraviroc treatment according to the FDA/European Medicines Agency (EMEA) label] group included both the CXCR4 (X4) samples and the dual and mixed CCR5/CXCR4 (R5/X4) samples. Compared with Trofile(TM) population PTTs, population GTTs showed a higher sensitivity (97%) and a higher negative predictive value (91%), but almost equal specificity and an equal positive predictive value. CONCLUSIONS: In line with recent reports from clinical trial data, our data support the use of population genotypic tropism testing as a tool for tropism determination before the start of maraviroc

Evolution of Hepatitis {C }Virus Quasispecies during Repeated Treatment with the {NS3}/{4A} Protease Inhibitor Telaprevir

In treating hepatitis B virus (HBV) and human immunodeficiency virus (HIV) infections, the rapid reselection of resistance-associated variants (RAVs) is well known in patients with repeated exposure to the same class of antiviral agents. For chronic hepatitis C patients who have experienced virologic failure with direct-acting antiviral drugs, the potential for the reselection of persistent RAVs is unknown. Nine patients who received 14 days of telaprevir monotherapy were retreated with telaprevir-based triple therapy 4.3 to 5.7 years later. In four patients with virologic failure with both telaprevir-containing regimens, population-based and deep sequencing (454 GS-FLX) of the NS3 protease gene were performed before and at treatment failure (median coverage, 4,651 reads). Using deep sequencing, with a threshold of 1.0% for variant calling, no isolates were found harboring RAVs at the baseline time points. While population-based sequencing uncovered similar resistance patterns (V36M plus R155K for subtype 1a and V36A for subtype 1b) in all four patients after the first and second telaprevir treatments, deep sequencing analysis revealed a median of 7 (range, 4 to 23) nucleotide substitutions on the NS3 backbone of the resistant strains, together with large phylogenetic differences between viral quasispecies, making the survival of resistant isolates highly unlikely. In contrast, in a comparison of the two baseline time points, the median number of nucleotide exchanges in the wild-type isolates was only 3 (range, 2 to 8), reflecting the natural evolution of the NS3 gene. In patients with repeated direct antiviral treatment, a continuous evolution of HCV quasispecies was observed, with no clear evidence of persistence and reselection but strong signs of independent de novo generation of resistance. Antiviral therapy for chronic viral infections, like HIV, hepatitis B virus (HBV), or hepatitis C virus (HCV), faces several challenges. These viruses have evolved survival strategies and proliferate by escaping the host's immune system. The development of direct-acting antiviral agents is an important achievement in fighting these infections. Viral variants conferring resistance to direct antiviral drugs lead to treatment failure. For HIV/HBV, it is well known that viral variants associated with treatment failure will be archived and reselected rapidly during retreatment with the same drug/class of drugs. We explored the mechanisms and rules of how resistant variants are selected and potentially reselected during repeated direct antiviral therapies in chronically HCV-infected patients. Interestingly, in contrast to HIV and HBV, we could not prove long-term persistence and reselection of resistant variants in HCV patients who failed protease inhibitor-based therapy. This may have important implications for the potential to reuse direct-acting antivirals in patients who failed the initial direct antiviral treatment. (The phase IIIb study described in this paper is registered at ClinicalTrials.gov under registration number NCT01054573.

Adult-limited dietary restriction slows gompertzian aging in Caenorhabditis elegans

Dietary restriction (DR) delays the onset of age-related deterioration and extends the life span in a variety of model organisms. In many species, age changes in mortality obey the Gompertz equation, which describes an exponential increase with age in age-specific mortality rate. Recently, this model has been used in fruitflies and rodents to investigate the mechanism by which DR reduces adult mortality. We report that food restriction imposed by axenic culture reduces the exponential increase of age-specific mortality of Caenorhabditis elegans. Furthermore, the life span appears largely independent of nutritional status during development, as shown by shifting worms to different food concentrations shortly before adulthood. When DR was exerted after reproduction, a smaller reduction in Gompertzian aging was seen. Thus, the demographic changes exerted by DR in C. elegans resemble those seen in rats, yet are different to those seen in Drosophila and mice

Obinutuzumab combined with lenalidomide for relapsed or refractory follicular B-cell lymphoma (GALEN): a multicentre, single-arm, phase 2 study.

ABSTRACT Background: Lenalidomide plus rituximab can treat patients with relapsed/refractory follicular lymphoma. Obinutuzumab enhances antibody-dependent cellular cytotoxicity, phagocytosis, and direct B-cell killing better than rituximab. Our aim was to determine efficacy and safety of lenalidomide plus obinutuzumab for treating relapsed/refractory follicular lymphoma. Methods: This is an ongoing, phase 2, open-label, multicenter study of patients with CD20- positive, relapsed/refractory follicular lymphoma (≥1 previous rituximab-containing regimen). Patients received oral lenalidomide 20 mg plus IV-infused obinutuzumab 1000 mg (six 28-day cycles; induction), 1-year maintenance with lenalidomide 10 mg ([12] 28-day cycles; days 2–22) plus obinutuzumab 1000 mg (alternate cycles), and 1-year maintenance with obinutuzumab 1000 mg (six 56-day cycles; day 1). Primary endpoint was overall response rate (ORR) at induction end per 1999 International Working Group criteria. Adverse events (AEs) were monitored. Findings: Eighty-six patients were evaluable for efficacy (88 for safety). ORR at induction end was 79·1% (95% CI, 68·9−87·1), meeting the pre-specified primary endpoint. Median follow-up for survival was 2·6 years (interquartile range, 2·2−2·8). At 2 years, event-free survival was 62.3% (95% CI, 51·1−71·7), progression-free survival 64·7% (95% CI, 53·5−73·8), duration of response 69·6% (95% CI, 57·2−79·0), and overall survival 86·9% (95% CI, 77·6−92·5). Most common AEs were asthenia (n=54, 61·4%), neutropenia (n=38, 43·2%), bronchitis (n=36, 40·9%), diarrhea (n=35, 39·8%), and muscle spasms (n=34, 38·6%). Neutropenia was the most common grade ≥3 toxicity; 4 (4·5%) patients had febrile neutropenia. Fifty-seven serious AEs were in 30/88 patients (34·1%); 18/88 (20·5%) deaths occurred (progressive lymphoma [n=10], infection [n=4], related cancer [n=1], and unknown cause [n=3]). No AEs were unanticipated. 6 Interpretations: Lenalidomide plus obinutuzumab is effective for patients with relapsed/refractory follicular lymphoma, including those with early relapse, with no increased toxicity compared with previous reports for lenalidomide plus rituximab. Funding: The Lymphoma Academic Research Organisation (LYSARC) sponsored the study, and Celgene and Roche provided investigator-initiated study grants