Update on combinations of DAAs with and without pegylated-interferon and ribavirin: triple and quadruple therapy more than doubles SVR

Discovery of functionalized bisimidazoles bearing cyclic aliphatic-phenyl motifs as HCV NS5A inhibitors

This Letter describes the discovery of a number of functionalized bisimidazoles bearing a cyclohexylphenyl, piperidylphenyl, or bicyclo[2,2,2]octylphenyl motif as HCV NS5A inhibitors. Compounds 2c, 4b and 6 have demonstrated low single-digit nM potency in gt-1a replicon and double-digit pM potency in gt-1b replicon, respectively. Moreover, both 4b and 6 have, respectively, exhibited good oral bioavailability in rats with a favorable liver/plasma ratio of the drug concentration.

Burden of pediatric hepatitis C

Hepatitis C virus (HCV) is a major health burden infecting 170-210 million people worldwide. Additional 3-4 millions are newly-infected annually. Prevalence of pediatric infection varies from 0.05%-0.36% in the United States and Europe; up to 1.8%-5.8% in some developing countries. The highest prevalence occurs in Egypt, sub-Saharan Africa, Amazon basin and Mongolia. HCV has been present in some populations for several centuries, notably genotypes 1 and 2 in West Africa. Parenteral anti-schistosomal therapy practiced in the 1960s until the early 1980s had spread HCV infection throughout Egypt. Parenteral acquisition of HCV remains a major route for infection among Egyptian children. Insufficient screening of transfusions, unsterilized injection equipment and re-used needles and syringes continue to be major routes of HCV transmission in developing countries, whereas vertical transmission and adolescent high-risk behaviors (e.g., injection drug abuse) are the major routes in developed countries. The risk of vertical transmission from an infected mother to her unborn/newborn infant is approximately 5%. Early stages of HCV infection in children do not lead to marked impairment in the quality of life nor to cognitive, behavioral or emotional dysfunction; however, caregiver stress and family system strain may occur. HCV slowly progresses to serious complications as cirrhosis (1%-2%) and hepatocellular carcinoma (HCC) especially in the presence of risk factors as hemolytic anemias, obesity, treated malignancy, and concomitant human immune deficiency and/or hepatitis B virus co-infection. HCV vaccine remains elusive to date. Understanding the immune mechanisms in patients who successfully cleared the infection is essential for vaccine development. The pediatric standard of care treatment consists of pegylated interferon-α 2a or b plus ribavirin for 24-48 wk. The new oral direct acting antivirals, approved for adults, need further evaluation in children. Sustained virologic response varies depending on the viral load, genotype, duration of infection, degree of aminotransferase elevation, adiposity and single nucleotide polymorphisms of interleukin (IL)-28B locus. The goals of treatment in individual patients are virus eradication, prevention of cirrhosis and HCC, and removing stigmatization; meanwhile the overall goal is decreasing the global burden of HCV. IL-28B polymorphisms have been also associated with spontaneous clearance of vertically acquired HCV infection. The worldwide economic burden of HCV for children, families and countries is estimated to be hundreds of millions of US dollars per year. The United States, alone, is estimated to spend 199-336 million dollars in screening, monitoring and treatment during one decade. The emotional burden of having an HCV infected child in a family is more difficult to estimate.

Interferon-associated retinopathy during the treatment of chronic hepatitis C: a systematic review

The incidence of retinopathy in patients with chronic hepatitis C treated with interferon-based regimens has been variably reported in the literature. There is no consensus regarding ophthalmologic screening before and during treatment with interferon-based therapy. To assess the incidence of retinopathy in patients with chronic hepatitis C being treated with interferon-based regimens and estimate the rate of resolution. A systematic literature search was performed to locate all relevant publications. Pooled incidence of retinopathy was calculated in patients treated with interferon or pegylated interferon. We also estimated the rate of discontinuation of treatment and resolution after the treatment was stopped. A total of 21 studies fulfilled the inclusion criteria. The overall incidence of retinopathy using random effect model was 27.7% (95% confidence interval [CI] 20.9-34.5%). The pooled incidence of retinopathy in 10 studies that only used pegylated interferon was 20.9% (95% CI: 11.6-29.8). The incidence of retinopathy with pegylated interferon in diabetic and hypertensive patients (high-risk group) was 65.32% and 50.7%, respectively. This was significantly higher compared with the incidence of retinopathy (11.7%) in patients without these risk factors. Overall pooled estimate for the resolution of retinopathy was 87% (95% CI 75.7-98.4%). The rate of discontinuation of treatment was 6.3%. The incidence of retinopathy with pegylated interferon in patients without hypertension and diabetes is low, but the risk is higher in patients with diabetes and hypertension. Routine pretreatment fundoscopic screening may not be warranted in all patients and can be limited to the patients with these risk factors.