Pegylated interferon 2a and 2b in combination with ribavirin for the treatment of chronic hepatitis C in HIV infected patients

Development and novel therapeutics in hepatocellular carcinoma: a review

This review summarizes the epidemiological trend, risk factors, prevention strategies such as vaccination, staging, current novel therapeutics, including the drugs under clinical trials, and future therapeutic trends for hepatocellular carcinoma (HCC). As HCC is the third most common cause of cancer-related death worldwide, its overall incidence remains alarmingly high in the developing world and is steadily rising across most of the developed and developing world. Over the past 15 years, the incidence of HCC has more than doubled and it increases with advancing age. Chronic infection with hepatitis B virus is the leading cause of HCC, closely followed by infection with hepatitis C virus. Other factors contributing to the development of HCC include alcohol abuse, tobacco smoking, and metabolic syndrome (including obesity, diabetes, and fatty liver disease). Treatment options have improved in the past few years, particularly with the approval of several molecular-targeted therapies. The researchers are actively pursuing novel therapeutic targets as well as predictive biomarker for treatment of HCC. Advances are being made in understanding the mechanisms underlying HCC, which in turn could lead to novel therapeutics. Nevertheless, there are many emerging agents still under clinical trials and yet to show promising results. Hence, future therapeutic options may include different combination of novel therapeutic interventions.

Faldaprevir and pegylated interferon α-2a/ribavirin in individuals co-infected with hepatitis C virus genotype-1 and HIV

OBJECTIVE

Faldaprevir is a potent, once-daily hepatitis C virus (HCV) NS3/4A protease inhibitor. STARTVerso4 assessed the efficacy and safety of faldaprevir and response-guided pegylated interferon α-2a/ribavirin (PegIFN/RBV) in individuals with HCV/HIV co-infection.

DESIGN

A phase 3 open-label study (NCT01399619).

METHODS

Individuals (N = 308) co-infected with HCV genotype 1 (treatment-naive or prior interferon relapsers) and HIV [96% on antiretroviral therapy (ART)] received faldaprevir 120 mg (N = 123) or 240 mg (N = 185) and PegIFN/RBV. Those receiving a protease inhibitor or efavirenz ART were assigned to faldaprevir 120 or 240 mg, respectively. Individuals achieving early treatment success (ETS; HCV RNA <25 IU/ml at week 4 and undetectable at week 8) were randomized to 24 or 48 weeks of PegIFN/RBV. The primary endpoint was sustained virologic response 12 weeks after treatment (SVR12).

RESULTS

SVR12 was achieved in 221 (72%) individuals, and the rates were comparable across faldaprevir doses. ETS was achieved in 80%, and of these 86% achieved SVR12, with comparable rates with 24 and 48 weeks of PegIFN/RBV (87 and 94%, respectively). In multivariate analysis, age below 40 years, IL28B CC genotype, and baseline HCV RNA below 800 000 IU/ml were associated with SVR12 (P = 0.027, P < 0.0001, and P = 0.0002, respectively), whereas treatment (ART regimen and faldaprevir dose), liver cirrhosis, and genotype 1 subtype were not. The safety profile was comparable to that of faldaprevir in HCV-monoinfected individuals.

CONCLUSIONS

High SVR12 rates were achieved with faldaprevir and PegIFN/RBV in HIV/HCV co-infected individuals, regardless of faldaprevir dose and background ART, HCV genotype 1 subtype, or cirrhosis status. SVR rates mirrored those obtained with similar regimens in HCV monoinfected individuals.

Mass spectrometric analysis of hepatitis C viral envelope protein E2 reveals extended microheterogeneity of mucin-type O-linked glycosylation

The infectious liver disease hepatitis C is caused by the small, enveloped, positive single-strand RNA hepatitis C virus (HCV). The HCV genome encodes for a single polyprotein precursor of ∼3010 amino acid residues. Host and cellular proteases co- and posttranslational process the precursor creating six nonstructural (NS) proteins and four structural components. Properly folded forms of the envelope proteins E1 and E2 form the associated E1-E2 complex. This complex represents a significant antigenic component at the viral surface that can interact with several target cell receptors. Extent and type of glycosylation is an important factor for virulence and escape from the immune system. Detailed characterization of the glycosylated sites is helpful for the understanding of different phenotypes as well as for the development of E1/E2-related treatments of HCV infection. Here, we have investigated in detail the O-linked glycosylation of the HCV envelope protein E2 expressed in and isolated from human embryonic kidney (HEK 293) cells. Using nano-liquid chromatography and tandem mass spectrometry approaches, we clearly have identified six residues for O-linked glycosylation within isolated glycopeptides (Ser393, Thr396, Ser401, Ser404, Thr473 and Thr518), carrying mainly Core 1 and Core 2 mucin-type structures. Based on our data, Thr385 is probably glycosylated as well. In addition, we could show that Ser479 within the hyper variable region (HVR) I is not O-glycosylated. For most of these sites, different degrees of microheterogeneity could be verified. Concerning HCV E2, this is the first case of experimentally proven O-linked glycosylation in detail via mass spectrometry.

Immune reconstitution of acquired immune deficiency syndrome

Acquired immune deficiency syndrome (AIDS) is a chronic infectious disease, which the patients are infected with human immunodeficiency virus (HIV). HIV damages the human's immune function and causes CD4 cell decline in the number and function. Immune reconstitution is an important treatment to AIDS. Bone marrow transplantation, adoptive immune cell therapy and cytokines infusion can all assist the immune reconstitution; highly active antiretroviral therapy (HAART) can effectively control the virus replication and benefit the immune reconstitution. HAART combined with immunotherapy is an important method of immune reconstitution in AIDS patients. Chinese medicine is playing a more and more important role in immune reconstitution. Immune reconstitution has always been effective in the whole treatment of AIDS.

Efficacy and safety of tenofovir disoproxil fumarate in patients with chronic hepatitis B

Chronic hepatitis B (CHB) is prevalent worldwide. It may cause cirrhosis and hepatocellular carcinoma. Treatment for this condition may need to be lifelong, thus the drugs used must be both efficacious and safe. Clinical trials of tenofovir have demonstrated a good safety profile for this drug and it has potent antiviral properties. However, to better characterize the safety of this drug, the postmarketing surveillance must be taken into account. Clinicians need to be vigilant, as infrequent adverse events may be revealed during this phase. The current review presents a detailed exposé of preclinical and clinical data on tenofovir to increase awareness of possible adverse events and drug-drug interactions, based on the large experience of this drug in human immunodeficiency virus (HIV) treatment (and to date in patients with CHB). Several recommendations that may help the clinician to prevent the development of adverse events associated with tenofovir disoproxil fumarate (TDF) treatment are outlined, along with a suggested surveillance protocol for the timely and proper identification of possible renal and bone toxicity.

Blocking hepatitis C virus infection with recombinant form of envelope protein 2 ectodomain

More than 120 million people worldwide are chronically infected with hepatitis C virus (HCV), making HCV infection the leading cause of liver transplantation in developed countries. Treatment is limited, and efficacy depends upon the infecting strain and the initial viral load. The HCV envelope glycoproteins (E1 and E2) are involved in receptor binding, virus-cell fusion, and entry into the host cell. HCV infection proceeds by endosomal acidification, suggesting that fusion of the viral envelope with cellular membranes is a pH-triggered event. E2 consists of an amino-terminal ectodomain, an amphipathic helix that forms a stem region, and a carboxy-terminal membrane-associating segment. We have devised a novel expression system for the production of a secreted form of E2 ectodomain (eE2) from mammalian cells and performed a comprehensive biochemical and biophysical characterization. eE2 is properly folded, as determined by binding to human CD81, blocking of infection of cell culture-derived HCV, and recognition by antibodies from patients chronically infected with different genotypes of HCV. The glycosylation pattern, number of disulfide bonds, oligomerization state, and secondary structure of eE2 have been characterized using mass spectrometry, size exclusion chromatography, circular dichroism, and analytical ultracentrifugation. These results advance the understanding of E2 and may assist in the design of an HCV vaccine and entry inhibitor.