Synergistic combinations of the CCR5 inhibitor VCH-286 with other classes of HIV-1 inhibitors.

Here, we evaluated the in vitro anti-HIV-1 activity of the experimental CCR5 inhibitor VCH-286 as a single agent or in combination with various classes of HIV-1 inhibitors. Although VCH-286 used alone had highly inhibitory activity, paired combinations with different drug classes led to synergistic or additive interactions. However, combinations with other CCR5 inhibitors led to effects ranging from synergy to antagonism. We suggest that caution should be exercised when combining CCR5 inhibitors in vivo.

Mutations in variable domains of the HIV-1 envelope gene can have a significant impact on maraviroc and vicriviroc resistance.

BACKGROUND: Resistance to CCR5 inhibitors, such as maraviroc and vicriviroc is characterized by reduction of maximal percent inhibition which indicates the use of an inhibitor-bound conformation of CCR5 for human immunodeficiency virus-1(HIV-1) entry. It is accompanied by substitutions in gp120 and gp41. Variable domain 3 (V3) plays the most important role, but substitutions outside V3 could also be involved in phenotype resistance. In this work, we investigated how mutations in variable regions of the viral envelope protein gp120 can contribute to CCR5 inhibitor resistance. METHODS: Resistant isolates were selected by passaging CC1/85 and BaL viruses with sub-inhibitory MVC and VCV concentrations. Mutations in gp160 were identified and mutants containing V2 (V169M), V3 (L317W) and V4 (I408T) were constructed. RESULTS: MVC and VCV susceptibility and viral tropism were assessed by single cycle assay. Mutant I408T showed 4-fold change (FC) increase in the half maximal inhibitory concentration (IC50) to MVC, followed by L317W (1.52-FC), V169M (1.23-FC), V169M/I408T (4-FC) L317W/I408T (3-FC), V169M/L317W (1.30-FC), and V169M/L317W/I408T (3.31-FC). MPI reduction was observed for mutants I408T (85%), L317W (95%), V169M/I408T (84%), L317W/I408T (85%) and V169M/L317W/I408T (83%). For VCV, I408T increased the IC50 by 2-FC and few mutants showed MPI reduction less than 95%: I408T (94%), L317W/I408T (94%) and V169M/L317W/I408T (94%). All mutants remained R5-tropic and presented decreased infectivity. CONCLUSIONS: These results suggest that mutations in the V4 loop of HIV-1 may contribute to MVC and VCV resistance alone or combined with mutations in V2 and V3 loops.

Real-World Incidence and Determinants of Infection in Patients With Rheumatoid Arthritis Treated With Golimumab After a Median Follow-Up Time of 27 Months.

OBJECTIVE: To characterize the long-term incidence of infection in patients with rheumatoid arthritis (RA) treated with subcutaneous golimumab (GOL) in Canadian routine care, assess the effect of infections on GOL retention, and explore factors associated with infection incidence. METHODS: Patients with RA enrolled in the Biologic Treatment Registry Across Canada (BioTRAC) initiating GOL treatment were included. The incidence density rates (IDRs) of total infection (TI), serious infection (SI), and nonserious infection (NSI) were calculated for the overall follow-up (90 months) and by 6-month intervals. Determinants of infection over time or within the first 6 months were explored using generalized estimating equation models and logistic regression, respectively. RESULTS: Five hundred thirty patients were included; mean baseline age was 57.7 years and RA duration was 8.0 years. Over an average follow-up of 27.0 months, the IDR for TIs was 35.1 events per 100 person-years (PYs), the majority occurring during the first 6 months; IDRs for NSIs and SIs were 32.9 and 2.2 events per 100 PYs, respectively. No predictors were identified for infection incidence within 6 months. Comorbid pulmonary disease was associated with significantly higher odds of TIs and NSIs over time, whereas higher age and high corticosteroid (CS) dose (> 5 mg/day) predicted higher odds of SIs. Incidence of SIs, but not NSIs, was associated with significantly higher odds of GOL discontinuation. CONCLUSION: Long-term GOL treatment was associated with relatively low infection rates, most being nonserious and occurring during the first 6 months. Pulmonary disease, higher age, and high CS dose were identified as significant predictors of infections. SIs, but not NSIs, predicted higher odds of GOL discontinuation. (ClinicalTrials.gov: NCT00741793).

Sustained low functional impairment in axial spondyloarthritis (axSpA): which are the primary outcomes that should be targeted to achieve this?

OBJECTIVES: To (i) determine whether sustained disease activity states, as measured by Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) and Ankylosing Spondylitis Disease Activity Score (ASDAS), impact function, and (ii) evaluate characteristics predicting sustained low functional impairment in a prospective axial spondyloarthritis (axSpA) cohort. METHODS: Biologic Treatment Registry Across Canada (BioTRAC) was a multi-center, prospective registry that collected real-world data on axSpA patients receiving infliximab or golimumab between 2006 and 2017. Generalized estimating equations (GEE) were used to test baseline characteristics, treatment, and duration (at 6 and 12 months vs. only at 6 or 12 months vs. neither) of low BASDAI (< 3), ASDAS-inactive disease (ID)(< 1.3), and ASDAS-low disease activity (LDA) in predicting sustained low Bath Ankylosing Spondylitis Functional Index (BASFI)(< 3) between 12 and 18 months. The adjusted impact of achieving low disease state at 6 and/or 12 months on BASFI at 18 months was analyzed by generalized linear models. RESULTS: Eight hundred ten patients were enrolled. 33.7%, 13.4%, and 24.7% achieved sustained low BASDAI, ASDAS-ID, and ASDAS-LDA, respectively. In univariable GEE of baseline variables, age and baseline BASDAI, BASFI, and ASDAS significantly predicted sustained low BASFI. In multivariable GEE, sustained low BASDAI (p < 0.001), low BASDAI only at 6 or 12 months (p = 0.001), and baseline BASFI (p < 0.001) were the only predictors of sustained low BASFI. Sustained ASDAS-ID (p = 0.040) and ASDAS-LDA (p < 0.001) were also predictors when forced into the model. Similar results were obtained when evaluating the BASFI score at 18 months. CONCLUSION: Sustained BASDAI < 3 may be a valid and feasible target for a treat-to-target strategy in axSpA having function as treatment goal.

A Systematic Review of the Clinical Diagnosis of Transient Hypogammaglobulinemia of Infancy.

Transient hypogammaglobulinemia of infancy (THI) is a primary immunodeficiency caused by a temporary decline in serum immunoglobulin G (IgG) levels greater than two standard deviations below the mean age-specific reference values in infants between 5 and 24 months of age. Preterm infants are particularly susceptible to THI, as IgG is only transferred across the placenta from mother to infant during the third trimester of pregnancy. This study aimed to conduct a systematic review of the diagnostic criteria for transient hypogammaglobulinemia of infancy. Systematic review: Three electronic databases (PubMed, MEDLINE, and Google Scholar) were manually searched from September 2021 to April 2022. Abstracts were screened to assess their fit to the inclusion criteria. Data were extracted from the selected studies using an adapted extraction tool (Cochrane). The studies were then assessed for bias using an assessment tool adapted from Cochrane. Of the 215 identified articles, 16 were eligible for examining the diagnostic criteria of THI. These studies were also assessed for bias in the six domains. A total of five studies (31%) had a low risk of bias, while four studies (25%) had a high risk of bias, and bias in the case of seven studies (44%) was unclear. We conclude that THI is only definitively diagnosed after abnormal IgG levels normalise. Hence, THI is not a benign condition, and monitoring for subsequent recurrent infections must be conducted. The diagnostic criteria should also include vaccine and isohaemagglutinin responses to differentiate THI from other immunological disorders in infants.

Chronic Granulomatous Disease (CGD): Commonly Associated Pathogens, Diagnosis and Treatment.

Chronic granulomatous disease (CGD) is a primary immunodeficiency caused by a defect in the phagocytic function of the innate immune system owing to mutations in genes encoding the five subunits of the nicotinamide adenine dinucleotide phosphatase (NADPH) oxidase enzyme complex. This review aimed to provide a comprehensive approach to the pathogens associated with chronic granulomatous disease (CGD) and its management. Patients with CGD, often children, have recurrent life-threatening infections and may develop infectious or inflammatory complications. The most common microorganisms observed in the patients with CGD are Staphylococcus aureus, Aspergillus spp., Candida spp., Nocardia spp., Burkholderia spp., Serratia spp., and Salmonella spp. Antibacterial prophylaxis with trimethoprim-sulfamethoxazole, antifungal prophylaxis usually with itraconazole, and interferon gamma immunotherapy have been successfully used in reducing infection in CGD. Haematopoietic stem cell transplantation (HCT) have been successfully proven to be the treatment of choice in patients with CGD.

Usage and Adherence of Seven Advanced Therapies with Differing Mechanisms of Action for Inflammatory Arthritis in Canada.

INTRODUCTION: This retrospective, observational study aimed to analyze and assess adherence, persistence, dosing, and use of concomitant medications of seven self-administered target drugs (abatacept, golimumab, secukinumab, tocilizumab, ustekinumab, apremilast, and tofacitinib) that are currently available in Canada for the treatment of inflammatory arthritis (IA). METHODS: We used IQVIA's longitudinal claims databases, which include private drug plans and public plans. Patients with IA identified using a proprietary indication algorithm who initiated treatment with any of the target drugs between January 2015 and February 2019 were selected and followed for 12 months. RESULTS: Golimumab and apremilast had the highest proportion of patients (~ 75%) who were bio-naïve and secukinumab had the fewest bio-naïve patients (~ 43%). The oral therapies, apremilast and tofacitinib, had the lowest percentage of adherent patients (73% and 71%) followed by abatacept (83%), while the remaining drugs had adherence around 90%. Secukinumab and tofacitinib had the highest 12-month persistence rate (63% and 61%), while abatacept and apremilast had the lowest persistence rate (52% and 47%). Oral corticosteroid (OCS) use was not significantly associated with adherence. Tocilizumab, secukinumab, and ustekinumab had the highest proportion of patients (> 20%) with dose escalation at 3-4 months from index. OCS and conventional disease-modifying antirheumatic drugs (cDMARD) use decreased in post-index period across all target drugs. CONCLUSION: This study identified substantial differences in patient baseline characteristics. Patients on injectable biologics were more likely to be adherent compared with those on oral drugs, possibly owing to longer dosing intervals. Other outcomes at 12 months appeared similar as evidenced by tapering of concomitant medications, although differences in persistence and dose escalation were noted.

Performance of a clonal-based HIV-1 tropism phenotypic assay.

Adequate determination of HIV-1 tropism is important in clinical and research settings. Genotypic and phenotypic approaches to evaluate tropism have been described. Phenotypic assays are widely used to determine HIV-1 tropism because of their sensitivity to detect minor CXCR4-using variants (X4). However they cannot differentiate mixed quasi-species of R5 and X4 viruses from dual-tropic viruses. We describe here a clonal-based HIV-1 tropism phenotypic assay. Env-pseudo-typed viruses were produced by co-transfection of the env expression plasmid pcDNA3.1/V5HisTOPO and a backbone vector pNL4-3.Luc.E-R- that expresses the entire HIV-1 genome except for env and vpr in 293T cell cultures. Co-receptor use was tested by infecting U87.CD4.CCR5+ and U87.CD4.CXCR4+ cells in the presence or absence of co-receptor inhibitors, using 10 clones from each sample. The ability of the assay to detect minor variants in a viral population was assessed by mixing X4 and R5 clones using different ratios. Both R5 and X4 minority variants were detected when present at greater than 0.4% in a mixture of envelope populations. This assay can be useful in both clinical and research laboratories.