Characterization of demographics and NS5A genetic diversity for hepatitis C virus genotype 4-infected patients with or without cirrhosis treated with ombitasvir/paritaprevir/ritonavir.

Hepatitis C virus (HCV) genotype 4 (GT4) is genetically diverse with 17 confirmed and 4 provisional subtypes. In this report, HCV GT4-infected patient samples from Phase 2/3 clinical studies were analysed to characterize global demographics and genetic diversity of GT4 infection among patients treated with ombitasvir (OBV, NS5A inhibitor) plus paritaprevir/r (NS3/4A inhibitor codosed with ritonavir). Among 17 subtypes isolated from GT4-infected patients in the PEARL-I and AGATE-I studies, subtype prevalence by country of enrolment and country of origin suggested that subtypes 4a and 4d were likely circulating in Europe, while heterogeneous GT4 subtypes and a portion of GT4a detected in European and North American countries were likely due to immigration of HCV-infected patients from Africa. The distributions of birth cohort and race were also significantly different across GT4 subtypes 4a, 4d, and non-4a/4d. In addition, phylogenetic analyses of NS5A sequences revealed clustering within subtype 4a which segregated by the patient-reported country of origin and the presence of the L30R/S polymorphism. HCV NS5A sequences derived from GT4a-infected patients who originated from Europe and the United States clustered separately from sequences derived from patients who originated from Egypt, suggesting that genetically distinct strains of subtype 4a may be circulating globally. Finally, NS5A baseline polymorphisms were frequently detected at amino acid positions of interest for the inhibitor-class and OBV retained activity against 37 of 39 NS5A GT4 clinical isolates, with no impact on treatment outcome in the PEARL-I and AGATE-I studies.

Grazoprevir plus peginterferon and ribavirin in treatment-naive patients with hepatitis C virus genotype 1 infection: a randomized trial.

UNLABELLED: Grazoprevir (MK-5172, Merck & Co., Inc.) is a selective inhibitor of the hepatitis C virus (HCV) NS3/4a protease. The aim of this study was to evaluate the safety and efficacy of grazoprevir at doses of 25-100 mg/day in combination with peginterferon and ribavirin (PEG-IFN/RBV). In this randomized, dose-ranging, multicentre trial, treatment-naive adults with chronic HCV genotype 1 infection received once-daily grazoprevir 25 mg, 50 mg or 100 mg plus PEG-IFN/RBV for 12 weeks. Patients with quantifiable HCV RNA (≥25 IU/mL) at week 4 received an additional 12 weeks of PEG-IFN/RBV. The primary endpoint was sustained virologic response (HCV RNA <25 IU/mL 12 weeks after completing therapy [SVR12]). Eighty-seven patients were randomly assigned and received ≥1 dose of therapy. Median time to undetectable HCV RNA was 16 days in the 100-mg arm and 22 days in the 25- and 50-mg arms. All patients except one had HCV RNA undetectable or unquantifiable at week 4 and received 12 weeks of therapy. SVR12 was achieved by 13 of 24 (54.2%), 21 of 25 (84.0%) and 23 of 26 (88.5%) patients in the 25-, 50- and 100-mg arms, respectively (per-protocol analysis). Three patients discontinued as a result of nonserious adverse events (AEs) and three patients experienced serious AEs. Transaminase elevations occurred in two patients (one each in the 25- and 100-mg arms). CONCLUSION: These data support further study of the grazoprevir 100-mg dose. Phase 3 studies of grazoprevir 100 mg in combination with elbasvir are currently ongoing (NCT01710501; protocol P038).

Randomized, double-blind study of stibogluconate plus human granulocyte macrophage colony-stimulating factor versus stibogluconate alone in the treatment of cutaneous Leishmaniasis.

The response to recombinant human granulocyte macrophage colony-stimulating factor (GM-CSF) in the treatment of cutaneous leishmaniasis was evaluated. Twenty patients with cutaneous leishmaniasis who had lesions for 60 days were enrolled in a double-blind placebo trial of GM-CSF with standard parenteral sodium stibogluconate (20 mg/kg-1/day-1) for 20 days. Ten patients were randomized to receive intralesionally injected GM-CSF (200 microgram) at enrollment and 1 week after, and 10 patients received saline as placebo. GM-CSF- and antimony-treated patients healed faster than patients who received antimony alone (49+/-32.8 vs. 110+/-61.6 days, P<.05). Seven of 10 patients were healed of their lesions before 40 days after therapy in the GM-CSF group, compared with only 1 of 10 patients in the placebo group (relative risk, 7; 95% confidence interval, 1.04-47.00). Thus, GM-CSF plus antimony significantly increased the chance of lesion healing in 40 days.

The conformational preference of gramicidin channels is a function of lipid bilayer thickness.

In order to understand how the material properties of lipid bilayers could affect integral membrane protein function, we examined the effect of a hydrophobic mismatch on the structure and function of membrane-spanning gramicidin channels. Changes in lipid bilayer thickness affect the conformational preference of membrane-spanning gramicidin A (gA) channels (single-stranded [SS] dimers <--> double-stranded [DS] dimers) and induces an additional conductance state in the standard (SS) beta6.3-helical channel. These results provide experimental evidence for the importance of energetic coupling between the bilayer and imbedded inclusions.