The emergence of drug resistant malaria parasites continues to hamper efforts to control this lethal disease. Dihydroorotate dehydrogenase has recently been validated as a new target for the treatment of malaria and a selective inhibitor (DSM265) of the Plasmodium enzyme is currently in clinical development. With the goal of identifying a backup compound to DSM265, we explored replacement of the SF5-aniline moiety of DSM265 with a series of CF3-pyridinyls, while maintaining the core triazolopyrimidine scaffold. This effort led to the identification of DSM421, which has improved solubility, lower intrinsic clearance and increased plasma exposure after oral dosing compared to DSM265, while maintaining a long predicted human half-life. Its improved physical and chemical properties will allow it to be formulated more readily than DSM265. DSM421 showed excellent efficacy in the SCID mouse model of P. falciparum malaria that supports the prediction of a low human dose (<200 mg). Importantly DSM421 showed equal activity against both P. falciparum and P. vivax field isolates, while DSM265 was more active on P. falciparum. DSM421 has the potential to be developed as a single dose cure or once-weekly chemopreventative for both P. falciparum and P. vivax malaria leading to its advancement as a preclinical development candidate.
Members of the Pim kinase family have been identified as promising targets for the development of antitumor agents. After a screening of pyrrolo[2,3-a]- and [3,2-a]carbazole derivatives toward 66 protein kinases, we identified pyrrolo[2,3-a]carbazole as a new scaffold to design potent Pim kinase inhibitors. In particular, compound 9 was identified as a low nM selective Pim inhibitor. Additionally, several pyrrolo[2,3-a]carbazole derivatives showed selectivity for Pim-1 and Pim-3 over Pim-2. In vitro antiproliferative activities of 9 and 28, the most potent Pim inhibitors identified, were evaluated toward three human solid cancer cell lines (PA1, PC3, and DU145) and one human fibroblast primary culture, revealing IC50 values in the micromolar range. Finally, the crystal structure of Pim-1 complexed with lead compound 9 was determined. The structure revealed a non-ATP mimetic binding mode with no hydrogen bonds formed with the kinase hinge region and explained the selectivity of pyrrolo[2,3-a]carbazole derivatives for Pim kinases.
Aims: This first-in-human clinical trial of P218, a novel dihydrofolate reductase inhibitor antimalarial candidate, assessed safety, tolerability, pharmacokinetics and food effects in healthy subjects.
Methods:The study consisted of two parts. Part A was a double-blind, randomized, placebo-controlled, parallel group, ascending dose study comprising seven fasted cohorts. Eight subjects/cohort were randomized (3:1) to receive either a single oral dose of P218 (10, 30, 100, 250, 500, 750 and 1000 mg) or placebo. Part B was an open-label, cross-over, fed/fasted cohort (eight subjects) that received a 250 mg single dose of P218 in two treatment periods.Results: P218 was generally well tolerated across all doses; 21 treatment-emergent adverse events occurred in 15/64 subjects. Nine adverse events in five subjects, all of mild intensity, were judged drug related. No clinically relevant abnormalities in ECG, vital signs or laboratory tests changes were observed. P218 was rapidly absorbed, with C max achieved between 0.5 and 2 hours post dose. Plasma concentrations declined bi-exponentially with half-life values ranging from 3.1 to 6.7 hours (10 and 30 mg), increasing up to 8.9 to 19.6 hours (doses up to 1000 mg). Exposure values increased dose-proportionally between 100 and 1000 mg for P218 (parent) and three primary metabolites (P218 β-acyl glucuronide, P218-OH and P218-OH β-acyl glucuronide). Co-administration of P218 with food reduced C max by 35% and delayed absorption by 1 hour, with no significant impact on AUC.Conclusion: P218 displayed favourable safety, tolerability and pharmacokinetics. In view of its short half-life, a long-acting formulation will be needed for malaria chemoprotection.The authors confirm that the PI for this paper is Ulrike Lorch and that she had direct clinical responsibility for patients.
[reaction: see text] Changing the identity of the N leaving group on a hydroxylamine-based reoxidant gives a dramatic improvement to the tethered aminohydroxylation reaction. Using OCOC6F5 as a leaving group means that only 1 mol % of osmium is required and yields as high as 98% can be obtained. Acyclic homoallylic alcohols were substrates considered too unreactive for effective use in the tethered aminohydroxylation reaction; improved reaction conditions mean that they have now become viable substrates for oxidation.
In this large prospective cohort of French middle-aged women, participants with greater flavonol, anthocyanin, and polymeric flavonoid intakes and greater total flavonoid intake were less likely to develop hypertension.
In this large prospective cohort of French women, we observed an association between the consumption of processed red meat and hypertension. We observed no association for unprocessed red meat consumption and hypertension.
Recurrence of hepatitis C virus (HCV) after liver transplantation (LT) can rapidly lead to liver graft cirrhosis and, therefore, graft failure and retransplantation or death. The aim of the present study was to assess efficacy and tolerance of sofosbuvir (SOF)-based regimens for the treatment of HCV recurrence in patients with severe fibrosis after LT. The Compassionate Use of Protease Inhibitors in Viral C Liver Transplantation (CULPIT) study is a prospective multicenter cohort including patients with HCV recurrence following LT treated with second generation direct antivirals. The present study focused on patients included between October 2013 and November 2014 and diagnosed with HCV recurrence and liver graft extensive fibrosis (METAVIR F3/F4). A SOF-based regimen was administered to 125 patients fulfilling inclusion criteria. The median delay from LT was 95.9 ± 69.6 months. The characteristics of patients were as follows: mean age, 59.4 ± 9.0 years; 78.4% male; infected by HCV genotype 1: 78.2%, mean HCV RNA: 6.1 ± 1.0 log10 IU/mL. Eighty patients had failed previous post-LT antiviral therapy (64.0%) including triple therapy with first generation protease inhibitors in 19 (15.2%) patients. The main combination regimen was SOF/daclatasvir (73.6%). Ribavirin was used in 60 patients. Sustained virological response 12 weeks after treatment was 92.8% (on an intention-to-treat basis); 7 patients with virological failure were observed. Serious adverse events occurred in 25.6% of the patients during antiviral treatment. During antiviral treatment and follow-up, 3 patients were retransplanted and 4 patients died. In conclusion, SOF-based antiviral treatment shows very promising results in patients with HCV recurrence and severe fibrosis after LT. Liver Transplantation 22 1367-1378 2016 AASLD.
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