The search for novel therapeutic interventions for viral disease is a challenging pursuit, hallmarked by the paucity of antiviral agents currently prescribed. Targeting of viral proteins has the ...inextricable challenge of rise of resistance. Safe and effective vaccines are not possible for many viral pathogens. New approaches are required to address the unmet medical need in this area. We undertook a cell-based high-throughput screen to identify leads for development of drugs to treat respiratory syncytial virus (RSV), a serious pediatric pathogen. We identified compounds that are potent (nanomolar) inhibitors of RSV in vitro in HEp-2 cells and in primary human bronchial epithelial cells and were shown to act postentry. Interestingly, two scaffolds exhibited broad-spectrum activity among multiple RNA viruses. Using the chemical matter as a probe, we identified the targets and identified a common cellular pathway: the de novo pyrimidine biosynthesis pathway. Both targets were validated in vitro and showed no significant cell cytotoxicity except for activity against proliferative B- and T-type lymphoid cells. Corollary to this finding was to understand the consequences of inhibition of the target to the host. An in vivo assessment for antiviral efficacy failed to demonstrate reduced viral load, but revealed microscopic changes and a trend toward reduced pyrimidine pools and findings in histopathology. We present here a discovery program that includes screen, target identification, validation, and druggability that can be broadly applied to identify and interrogate other host factors for antiviral effect starting from chemical matter of unknown target/mechanism of action.
Mast cells play a significant role in inflammatory diseases such as asthma, inflammatory bowel disease, and autoimmune diseases. Inhibition of c-kit receptor tyrosine kinase, a growth factor ...receptor, significantly reduces mast cell numbers. The purpose of this study was to determine the effect of Compound X (a c-kit inhibitor) on mast cell numbers in rats. Connective tissue mast cells (CTMCs) and mucosal mast cells (MMCs) have differing histochemical characteristics which presents a challenge when staining for quantification by semi-automated image analysis. CTMCs are present in tissues such as tongue and skin and will stain readily in tissues fixed routinely. In contrast, MMCs, such as those present in the intestinal mucosa, are sensitive to fixation. Brief fixation in Carnoy's solution, although seldom used due to its composition (a mixture of ethanol, chloroform, and acetic acid), was employed to fix tissues for MMC staining, while tissues for CTMC demonstration were fixed in 10% neutral buffered formalin. An enzyme histochemistry method, napthol AS-D choloroacetate (specific esterase), was briefly considered for staining; however, granulocytes stained along with mast cells, requiring manual identification and exclusion, thereby rendering the method incompatible with automated means of quantification. Instead, staining was performed using two different toluidine blue methods which have proven conducive to semi-automated image analysis techniques. CTMCs were stained using Luna's toluidine blue, while MMCs were stained with Matsson's toluidine blue modification. In summary, the selected methods, based upon a conventional stain, were easy to do and successfully identified both populations of mast cells for quantification by image analysis.
Sutimlimab, a first-in-class humanized immunoglobulin G4 (IgG4) monoclonal antibody that selectively inhibits the classical complement pathway at C1s, rapidly halted hemolysis in the single-arm ...CARDINAL study in recently transfused patients with cold agglutinin disease (CAD). CADENZA was a 26-week randomized, placebo-controlled phase 3 study to assess safety and efficacy of sutimlimab in patients with CAD without recent (within 6 months prior to enrollment) transfusion history. Forty-two patients with screening hemoglobin ≤10 g/dL, elevated bilirubin, and ≥1 CAD symptom received sutimlimab (n = 22) or placebo (n = 20) on days 0 and 7 and then biweekly. Composite primary endpoint criteria (hemoglobin increase ≥1.5 g/dL at treatment assessment timepoint mean of weeks 23, 25, 26, avoidance of transfusion, and study-prohibited CAD therapy weeks 5-26) were met by 16 patients (73%) on sutimlimab, and 3 patients (15%) on placebo (odds ratio, 15.9 95% confidence interval, 2.9, 88.0; P < .001). Sutimlimab, but not placebo, significantly increased mean hemoglobin and FACIT-Fatigue scores at treatment assessment timepoint. Sutimlimab normalized mean bilirubin by week 1. Improvements correlated with near-complete inhibition of the classical complement pathway (2.3% mean activity at week 1) and C4 normalization. Twenty-one (96%) sutimlimab patients and 20 (100%) placebo patients experienced ≥1 treatment-emergent adverse event. Headache, hypertension, rhinitis, Raynaud phenomenon, and acrocyanosis were more frequent with sutimlimab vs placebo, with a difference of ≥3 patients between groups. Three sutimlimab patients discontinued owing to adverse events; no placebo patients discontinued. These data demonstrate that sutimlimab has potential to be an important advancement in the treatment of CAD. This trial was registered at www.clinicaltrials.gov as #NCT03347422.
•Sutimlimab reduced hemolysis, anemia, and fatigue in patients with CAD without transfusion requirement.•Sutimlimab treatment was generally well tolerated, with adverse events consistent with an older and medically complex patient population.
Display omitted
Systems thinking dominated the 2015 World Social Marketing conference with the premise that a more holistic approach takes into account all the issues at play for effective change. Augmenting the ...broadening social marketing literature, we contend that systems-thinking social marketing enhances the field's conventional behavioural change with concepts of scale, causation, and iterative co-creating change processes for complex health and environmental problems. The results of our empirical Sea for Society study, a sustainable European marine ecosystem examination of what the barriers to change are and how they are interrelated, find systems-thinking social marketing offers the potential to strategically and critically reinforce, not replace, behavioural change campaigns. With systems-thinking social marketing, a coherent theory of change becomes a possibility. Orchestrating social change may become a reality.
Abstract Case-control studies are commonly used to evaluate effectiveness of licensed vaccines after deployment in public health programs. Such studies can provide policy-relevant data on vaccine ...performance under ‘real world’ conditions, contributing to the evidence base to support and sustain introduction of new vaccines. However, case-control studies do not measure the impact of vaccine introduction on disease at a population level, and are subject to bias and confounding, which may lead to inaccurate results that can misinform policy decisions. In 2012, a group of experts met to review recent experience with case-control studies evaluating the effectiveness of several vaccines; here we summarize the recommendations of that group regarding best practices for planning, design and enrollment of cases and controls. Rigorous planning and preparation should focus on understanding the study context including healthcare-seeking and vaccination practices. Case-control vaccine effectiveness studies are best carried out soon after vaccine introduction because high coverage creates strong potential for confounding. Endpoints specific to the vaccine target are preferable to non-specific clinical syndromes since the proportion of non-specific outcomes preventable through vaccination may vary over time and place, leading to potentially confusing results. Controls should be representative of the source population from which cases arise, and are generally recruited from the community or health facilities where cases are enrolled. Matching of controls to cases for potential confounding factors is commonly used, although should be reserved for a limited number of key variables believed to be linked to both vaccination and disease. Case-control vaccine effectiveness studies can provide information useful to guide policy decisions and vaccine development, however rigorous preparation and design is essential.
Cold agglutinin disease (CAD) is a rare, autoimmune, classical complement pathway (CP)-mediated hemolytic anemia. Sutimlimab selectively inhibits C1s of the C1 complex, preventing CP activation while ...leaving the alternative and lectin pathways intact. In Part A (26 weeks) of the open-label, single-arm, Phase 3 CARDINAL study in patients with CAD and a recent history of transfusion, sutimlimab demonstrated rapid effects on hemolysis and anemia. Results of the CARDINAL study Part B (2-year extension) study, described herein, demonstrated that sutimlimab sustains improvements in hemolysis, anemia, and quality of life over a median of 144 weeks of treatment. Mean last-available on-treatment values in Part B were improved from baseline for hemoglobin (12.2 g/dL on-treatment versus 8.6 g/dL at baseline), bilirubin (16.5 μmol/L on-treatment versus 52.1 μmol/L at baseline), and FACIT-Fatigue scores (40.5 on-treatment versus 32.4 at baseline). In the 9-week follow-up period after sutimlimab cessation, CP inhibition was reversed, and hemolytic markers and fatigue scores approached pre-sutimlimab values. Overall, sutimlimab was generally well tolerated in Part B. All 22 patients experienced ≥1 treatment-emergent adverse event (TEAE); 12 (54.5%) patients experienced ≥1 serious TEAE, including seven (31.8%) with ≥1 serious infection. Three patients discontinued due to a TEAE. No patients developed systemic lupus erythematosus or meningococcal infections. After cessation of sutimlimab, most patients reported adverse events consistent with recurrence of CAD. In conclusion, the CARDINAL 2-year results provide evidence of sustained sutimlimab effects for CAD management, but that disease activity reoccurs after treatment cessation. NCT03347396. Registered November 20, 2017.
Cold agglutinin disease (CAD) is a rare chronic autoimmune haemolytic anaemia, driven mainly by classical complement pathway activation, leading to profound fatigue and poor quality of life. In the ...Phase 3 CADENZA trial, sutimlimab—a C1s complement inhibitor—rapidly halted haemolysis, increased haemoglobin levels and improved fatigue versus placebo in patients with CAD without a recent history of transfusion. Patient‐reported outcomes (PROs) included Functional Assessment of Chronic Illness Therapy–Fatigue (FACIT‐Fatigue), 12‐Item Short Form Health Survey (SF‐12), EuroQol visual analogue scale (EQ‐VAS), Patient Global Impression of Change (PGIC) and Patient Global Impression of (fatigue) Severity (PGIS). Sutimlimab resulted in significant rapid and meaningful improvements versus placebo in PROs. From Week 1, the FACIT‐Fatigue mean score increased >5 points above baseline (considered a clinically important change CIC). Least‐squares (LS) mean change in FACIT‐Fatigue score from baseline to treatment assessment timepoint was 10.8 vs. 1.9 points (sutimlimab vs. placebo; p < 0.001). Improvements in physical (PCS) and mental (MCS) component scores of the SF‐12 were also considered CICs (LS mean changes from baseline to Week 26: PCS 5.54 vs. 1.57 p = 0.064; MCS 5.65 vs. –0.48 p = 0.065). These findings demonstrate that in addition to improving haematologic parameters, sutimlimab treatment demonstrates significant patient‐reported benefits. Study registered at www.clinicaltrials.gov: NCT03347422.
PDF
