Efficacy and safety of tafamidis doses in the Tafamidis in Transthyretin Cardiomyopathy Clinical Trial (ATTR-ACT) and long-term extension study.

Aims Tafamidis is an effective treatment for transthyretin amyloid cardiomyopathy (ATTR-CM) in the Tafamidis in Transthyretin Cardiomyopathy Clinical Trial (ATTR-ACT). While ATTR-ACT was not designed for a dose-specific assessment, further analysis from ATTR-ACT and its long-term extension study (LTE) can guide determination of the optimal dose. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Methods and results In ATTR-ACT, patients were randomized (2:1:2) to tafamidis 80 mg, 20mg, or placebo for 30months. Patients completing ATTR-ACT could enrol in the LTE (with placebo-treated patients randomized to tafamidis 80 or 20 mg; 2:1) and all patients were subsequently switched to high-dose tafamidis. All-cause mortality was assessed in ATTR-ACT combined with the LTE (median follow-up 51 months). In ATTR-ACT, the combination of all-cause mortality and cardiovascular-related hospitalizations over 30 months was significantly reduced with tafamidis 80mg (P = 0.0030) and 20mg (P = 0.0048) vs. placebo. All-cause mortality vs. placebo was reduced with tafamidis 80mg [Cox hazards model (95% confidence interval (CI): 0.690 (0.487–0.979), P = 0.0378] and 20mg [0.715 (0.450–1.137), P = 0.1564]. The mean (standard error) change in N-terminal pro-B-type natriuretic peptide from baseline to Month 30 was −1170.51 (587.31) (P = 0.0468) with tafamidis 80 vs. 20 mg. In ATTR-ACT combined with the LTE there was a significantly greater survival benefit with tafamidis 80 vs. 20 mg [0.700 (0.501–0.979), P = 0.0374]. Incidence of adverse events in both tafamidis doses were comparable to placebo. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Conclusion Tafamidis, both 80 and 20mg, effectively reduced mortality and cardiovascular-related hospitalizations in patients with ATTR-CM. The longer-term survival data and the lack of dose-related safety concerns support tafamidis 80mg as the optimal dose. Clinical Trial Registration: ClinicalTrials.gov NCT01994889; NCT02791230post-print369 K

Volatile Sulfur Compounds in Foods as a Result of Ionizing Radiation

Ionizing radiation improves food safety and extends shelf life by inactivating food-borne pathogens and spoilage microorganisms. However, irradiation may induce the development of an off-odor, particularly at high doses. The off-odor has been called “irradiation odor”. Substantial evidence suggests that volatile sulfur compounds (VSCs) play an important role in the development of the off-odor. These compounds include hydrogen sulfide, methanethiol, methyl sulfide, dimethyl disulfide and dimethyl trisulfide among others. The formation of off-odor and VSCs due to irradiation in meat, and fruit juices is presented. It is known that irradiation exerts its effect through radiolysis of water in foods where water is a dominant component. Irradiation of water produces three primary free radicals: hydroxyl, hydrogen atoms, and hydrated electrons. Use of specific scavengers in a model system revealed that hydroxyl radicals are involved in the formation of VSCs. Possible mechanisms for formation of VSC are also discussed. Also discussed are possible remedies for formation of VSCs and off-odor, such as use of antioxidants and double packaging

A 1-year analysis from a natural history study in Chinese individuals with Duchenne muscular dystrophyResearch in context

Summary: Background: Duchenne muscular dystrophy (DMD) is a disabling and life-threatening, X-linked recessive disorder caused by mutations in dystrophin. Natural history studies can inform the disease characteristics of DMD, and data from these studies can be used to plan and design clinical trials and as external controls for long-term studies. We report 12-month results from the largest natural history study of individuals with DMD in China receiving standard of care treatment. Methods: This ongoing, multicentre, prospective, single-cohort study (ClinicalTrials.gov: NCT03760029) was conducted in Chinese male participants with DMD (ambulatory aged <6 years [Group 1; n = 99]; ambulatory aged ≥6 years [Group 2; n = 177], and non-ambulatory of any age [Group 3; n = 36]. The follow-up period is ≥24 months, with some participants followed for 30 months. The primary endpoint was time to clinical milestones due to DMD disease progression, and motor, pulmonary, and cardiac function. Secondary endpoints were quality of life (QoL) assessments. Findings: Mean (standard deviation [SD]) age at screening was 3.4 (1.2), 8.6 (2.0), 12.3 (2.7) and 7.4 (3.5) years in Groups 1, 2, 3 and total respectively. Mean (SD) North Star Ambulatory Assessment (NSAA) total score at baseline was 21.2 (5.8) in Group 1, 19.5 (8.3) in Group 2 and 20.0 (7.7) in ambulatory total. Overall, the time to clinical milestones due to DMD disease progression was consistent with previous findings, in which loss of ambulation occurred at 13 years. There was a trend towards a decline over 12 months in NSAA and timed motor function from age 6 years, with the greatest reductions observed thereafter. There were no consistent trends in measures of QoL, although participants of any age generally had poorer outcomes at Month 12 versus their domain scores at baseline. Interpretation: This study improves the understanding of DMD progression according to the current standards of care in the Chinese DMD population and may inform selected endpoints and patient populations in clinical trials. Funding: Pfizer Inc

Evaluation of a Mathematical Model of Rat Body Weight Regulation in Application to Caloric Restriction and Drug Treatment Studies.

The purpose of this work is to develop a mathematical model of energy balance and body weight regulation that can predict species-specific response to common pre-clinical interventions. To this end, we evaluate the ability of a previously published mathematical model of mouse metabolism to describe changes in body weight and body composition in rats in response to two short-term interventions. First, we adapt the model to describe body weight and composition changes in Sprague-Dawley rats by fitting to data previously collected from a 26-day caloric restriction study. The calibrated model is subsequently used to describe changes in rat body weight and composition in a 23-day cannabinoid receptor 1 antagonist (CB1Ra) study. While the model describes body weight data well, it fails to replicate body composition changes with CB1Ra treatment. Evaluation of a key model assumption about deposition of fat and fat-free masses shows a limitation of the model in short-term studies due to the constraint placed on the relative change in body composition components. We demonstrate that the model can be modified to overcome this limitation, and propose additional measurements to further test the proposed model predictions. These findings illustrate how mathematical models can be used to support drug discovery and development by identifying key knowledge gaps and aiding in the design of additional experiments to further our understanding of disease-relevant and species-specific physiology

Inflammatory and apoptotic signalling pathways and concussion severity: a genetic association study

The objective was to investigate the relationship between IL-1B rs16944, IL-6 rs1800795, and CASP8 rs3834129 genetic polymorphisms and concussion severity. Rugby players from high school, senior amateur, and professional teams completed a concussion severity questionnaire and donated a DNA sample. Participants (n = 163) were split into symptom severity groups around the median number and duration of symptoms. The frequency of participants with high symptom counts (more than five symptoms) increased across the IL-1B (C/C: 35%; C/T: 51%; T/T: 56%; P = 0.047) and the IL-6 (C/C: 31%; C/G: 44%; G/G: 58%; P = 0.027) genotypes. The C–C inferred interleukin allele construct frequency, created from combining the IL-1B and IL-6 genotype data, was lower in participants reporting a high symptom count (18%), compared to those with a low symptom count (fewer than six symptoms, 36%, P = 0.002). Similarly, the C–C inferred interleukin allele construct frequency was lower in those reporting prolonged symptom duration (more than one week, 16%), as opposed to short symptom duration (less than one week, 34%, P = 0.015). This study provides evidence of novel inflammatory pathway genetic associations with concussion severity, which supports the hypothesis implicating neuroinflammation in the development of concussion symptoms.The National Research Foundation funded the study (A.V.S., grant number 90942), (M.P., grant numbers 93416:2015, 85534:2015). The National Research Foundation and the University of Cape Town funded S.A. and S.M.https://www.tandfonline.com/loi/rjsp202019-03-06hj2019Sports Medicin

Model calibration against CB1Ra data.

<p>The calibrated model shows good agreement between model simulations (black) and experimental BW (A). The fitted model trajectories show poor agreement with FFM (B) and FM (C) measurements at the three drug dose levels. Gray region indicates the intervention phase in each study. Error bars represent SEM (9-10 rats).</p

The α-free model fits BC in CR and CB1Ra BC studies.

<p>Simulations (black) of the <i>α</i>-free model show agreement with FFM (red) and FM (yellow) measurements in CR (A) and CB1Ra (B) intervention studies. Gray region indicates treatment phases in the two studies. Error bars represent SEM (9-10 rats).</p

Efficacy of Tafamidis in Patients With Hereditary and Wild-Type Transthyretin Amyloid Cardiomyopathy : Further Analyses From ATTR-ACT

Objectives: Tafamidis is an effective treatment for transthyretin amyloid cardiomyopathy (ATTR-CM), this study aimed to determine whether there is a differential effect between variant transthyretin amyloidosis (ATTRv) and wild-type transthyretin (ATTRwt). Background: ATTR-CM is a progressive, fatal disorder resulting from mutations in the ATTRv or the deposition of denatured ATTRwt. Methods: In pre-specified analyses from ATTR-ACT (Tafamidis in Transthyretin Cardiomyopathy Clinical Trial), baseline characteristics, all-cause mortality, and change from baseline to month 30 in 6-min walk test distance and Kansas City Cardiomyopathy Questionnaire Overall Summary score were compared in patients with ATTRwt and ATTRv. Results: There were 335 patients with ATTRwt (201 tafamidis, 134 placebo) and 106 with ATTRv (63 tafamidis, 43 placebo) enrolled in ATTR-ACT. Patients with ATTRwt (vs. ATTRv) had less advanced disease at baseline and a lower rate of disease progression over the study. The reduction in all-cause mortality with tafamidis compared with placebo was not different between ATTRwt (hazard ratio: 0.706 [95% confidence interval (CI): 0.474 to 1.052]; p = 0.0875) and ATTRv (hazard ratio: 0.690 [95% CI: 0.408 to 1.167]; p = 0.1667). Tafamidis was associated with a similar reduction (vs. placebo) in the decline in 6-min walk test distance in ATTRwt (mean ± SE difference from placebo, 77.14 ± 10.78; p &lt; 0.0001) and ATTRv (79.61 ± 29.83 m; p = 0.008); and Kansas City Cardiomyopathy Questionnaire Overall Summary score in ATTRwt (12.72 ± 2.10; p &lt; 0.0001) and ATTRv (18.18 ± 7.75; p = 0.019). Conclusions: Pre-specified analyses from ATTR-ACT confirm the poor prognosis of untreated ATTRv-related cardiomyopathy compared with ATTRwt, but show the reduction in mortality and functional decline with tafamidis treatment is similar in both disease subtypes. (Safety and Efficacy of Tafamidis in Patients With Transthyretin Cardiomyopathy [ATTR-ACT]; NCT01994889