Real-world evaluation of effectiveness, persistence, and usage patterns of tofacitinib in treatment of rheumatoid arthritis in Australia.

INTRODUCTION: The aim of this study was to describe the real-world evidence for effectiveness, treatment persistence, and treatment patterns among patients in the community with rheumatoid arthritis treated with the JAK inhibitor tofacitinib. METHODS: This was a retrospective, non-interventional cohort study that extracted data for new users of tofacitinib or biologic disease-modifying antirheumatic drugs (bDMARDs) from the Australian Optimizing Patient outcomes in Australian RheumatoLogy (OPAL) dataset between March 2015 and September 2018. Patients were propensity score matched at a 1:2 tofacitinib to bDMARD ratio based on age, sex, and selected baseline treatment combinations. Treatment effectiveness was evaluated using disease status measures. Treatment persistence was calculated and the percentage of patients receiving monotherapy or combination therapy at treatment initiation was evaluated. RESULTS: Data from 2810 patients were extracted and 1950 patients were included in the matched population (1300 bDMARD initiators and 650 tofacitinib initiators). Patients were predominantly aged 55 to 74 years (57.8%) and female (81.2%). After 18 months of treatment, 52.4% and 57.8% of patients had achieved disease activity score (DAS) remission in the bDMARD and tofacitinib groups, respectively. The median treatment persistence for tofacitinib was similar to that for bDMARDs: 34.2 months (95% CI 32.2 to not reached) and 33.8 months (95% CI 28.8 to 40.4), respectively. In the overall population, more patients were prescribed tofacitinib as monotherapy (43.4%) compared with bDMARD monotherapy (33.4%). CONCLUSIONS: Tofacitinib demonstrated treatment effectiveness and persistence similar to bDMARDs. Overall, there was a trend for more use of tofacitinib as monotherapy than bDMARDs. Key Points • This study provides real-world evidence regarding effectiveness, treatment persistence, and treatment patterns, among patients with rheumatoid arthritis (RA) in the community being treated with tofacitinib. • The study suggests that tofacitinib is an effective and enduring intervention in RA with tofacitinib persistence and effectiveness comparable to bDMARDs.

The role of antigen presenting cells in the induction of HIV-1 latency in resting CD4(+) T-cells.

BACKGROUND: Combination antiretroviral therapy (cART) is able to control HIV-1 viral replication, however long-lived latent infection in resting memory CD4(+) T-cells persist. The mechanisms for establishment and maintenance of latent infection in resting memory CD4(+) T-cells remain unclear. Previously we have shown that HIV-1 infection of resting CD4(+) T-cells co-cultured with CD11c(+) myeloid dendritic cells (mDC) produced a population of non-proliferating T-cells with latent infection. Here we asked whether different antigen presenting cells (APC), including subpopulations of DC and monocytes, were able to induce post-integration latent infection in resting CD4(+) T-cells, and examined potential cell interactions that may be involved using RNA-seq. RESULTS: mDC (CD1c(+)), SLAN(+) DC and CD14(+) monocytes were most efficient in stimulating proliferation of CD4(+) T-cells during syngeneic culture and in generating post-integration latent infection in non-proliferating CD4(+) T-cells following HIV-1 infection of APC-T cell co-cultures. In comparison, plasmacytoid DC (pDC) and B-cells did not induce latent infection in APC-T-cell co-cultures. We compared the RNA expression profiles of APC subpopulations that could and could not induce latency in non-proliferating CD4(+) T-cells. Gene expression analysis, comparing the CD1c(+) mDC, SLAN(+) DC and CD14(+) monocyte subpopulations to pDC identified 53 upregulated genes that encode proteins expressed on the plasma membrane that could signal to CD4(+) T-cells via cell-cell interactions (32 genes), immune checkpoints (IC) (5 genes), T-cell activation (9 genes), regulation of apoptosis (5 genes), antigen presentation (1 gene) and through unknown ligands (1 gene). CONCLUSIONS: APC subpopulations from the myeloid lineage, specifically mDC subpopulations and CD14(+) monocytes, were able to efficiently induce post-integration HIV-1 latency in non-proliferating CD4(+) T-cells in vitro. Inhibition of key pathways involved in mDC-T-cell interactions and HIV-1 latency may provide novel targets to eliminate HIV-1 latency.

Myeloid dendritic cells induce HIV-1 latency in non-proliferating CD4+ T cells.

Latently infected resting CD4(+) T cells are a major barrier to HIV cure. Understanding how latency is established, maintained and reversed is critical to identifying novel strategies to eliminate latently infected cells. We demonstrate here that co-culture of resting CD4(+) T cells and syngeneic myeloid dendritic cells (mDC) can dramatically increase the frequency of HIV DNA integration and latent HIV infection in non-proliferating memory, but not naïve, CD4(+) T cells. Latency was eliminated when cell-to-cell contact was prevented in the mDC-T cell co-cultures and reduced when clustering was minimised in the mDC-T cell co-cultures. Supernatants from infected mDC-T cell co-cultures did not facilitate the establishment of latency, consistent with cell-cell contact and not a soluble factor being critical for mediating latent infection of resting CD4(+) T cells. Gene expression in non-proliferating CD4(+) T cells, enriched for latent infection, showed significant changes in the expression of genes involved in cellular activation and interferon regulated pathways, including the down-regulation of genes controlling both NF-κB and cell cycle. We conclude that mDC play a key role in the establishment of HIV latency in resting memory CD4(+) T cells, which is predominantly mediated through signalling during DC-T cell contact.

Tissue-type plasminogen activator is an extracellular mediator of Purkinje cell damage and altered gait.

Purkinje neurons are a sensitive and specialised cell type important for fine motor movement and coordination. Purkinje cell damage manifests as motor incoordination and ataxia - a prominent feature of many human disorders including spinocerebellar ataxia and Huntington's disease. A correlation between Purkinje degeneration and excess cerebellar levels of tissue-type plasminogen activator (tPA) has been observed in multiple genetically-distinct models of ataxia. Here we show that Purkinje loss in a mouse model of Huntington's disease also correlates with a 200% increase in cerebellar tPA activity. That elevated tPA levels arise in a variety of ataxia models suggests that tPA is a common mediator of Purkinje damage. To address the specific contribution of tPA to cerebellar dysfunction we studied the T4 mice line that overexpresses murine tPA in postnatal neurons through the Thy1.2 gene promoter, which directs preferential expression to Purkinje cells within the cerebellum. Here we show that T4 mice develop signs of cerebellar damage within 10 weeks of birth including atrophy of Purkinje cell soma and dendrites, astrogliosis, reduced molecular layer volume and altered gait. In contrast, T4 mice displayed no evidence of microgliosis, nor any changes in interneuron density, nor alteration in the cerebellar granular neuron layer. Thus, excess tPA levels may be sufficient to cause targeted Purkinje cell degeneration and ataxia. We propose that elevated cerebellar tPA levels exert a common pathway of Purkinje cell damage. Therapeutically lowering cerebellar tPA levels may represent a novel means of preserving Purkinje cell integrity and motor coordination across a wide range of neurodegenerative diseases.