Effect of Boceprevir on HCV-specific T Cell Responses

Reconstitution of the antiviral T cell function may represent a component of the anti-viral effect of protease inhibitors. If T cell responsiveness is restored under therapy, potentiation of anti-viral T cell functions by exogenous T cell stimulation might be exploited to complement and to further improve response to available therapies. Monitoring the T cell function might also be useful to predict more accurately response to therapy.

To address these issues, phenotype and function of HCV-specific T cells will be analyzed longitudinally before, during and after therapy in naïve genotype 1 chronic hepatitis C patients treated with peginterferon plus ribavirin or with peginterferon and ribavirin plus boceprevir. To analyze the global CD4 and CD8 reactivity against all structural and non-structural HCV proteins a wide panel of peptides corresponding to the whole HCV genome of genotype 1 will be employed. To further analyze CD8 reactivity, HLA-A2/peptide tetramers will be used in HLA-A2 positive patients to directly quantify ex vivo HCV-specific CD8 cells circulating in the peripheral blood.The T cell function will be analyzed as capacity of expansion in vitro, cytokine production and cytotoxicity.

Inclusion criteria

Subjects must meet all of the following inclusion criteria to be eligible for participation in this study.

• Male or female, aged from 18 to 70 years old, inclusive.
• Willing and able to provide written informed consent
• Chronic HCV infection for at least 6 month prior to baseline (Day 1) in subjects currently positive for HCV-RNA and anti-HCV antibody documented by:
• A positive anti-HCV antibody test, positive HCV-RNA assay, or HCV genotype test at least 6 month prior to baseline (Day 1) or
• A liver biopsy performed prior to baseline (Day 1) with evidence of chronic HCV infection
• Subjects must have liver biopsy results (performed no more than two years prior the screening) indicating the absence of cirrhosis
• HCV infection limited to genotype 1
• Detectable plasma HCV-RNA at screening
• BMI between 18 and 36 Kg/m2
• Eligible subjects must also be HCV treatment-naïve, defined as no prior exposure to PEG-INF and ribavirin, and must be eligible to standard of care therapy with PEG/RBV
• Subjects must have the following laboratory parameters at screening:

ALT and AST ≤ 5 x upper limit of normal range (ULN) Hemoglobin (Hb) ≥ 12 g/dl WBC ≥ 2.500 cells/μL with absolute neutrophil count ≥ 1500 cells/μL If a woman of childbearing potential, must have negative serum β-human chorionic gonadotropin (β-HCG) pregnancy test documented at the screening visit and a negative serum or urine pregnancy test before the first dose of study drug to ensure that they are not pregnant at the time of starting treatment A female subjects of childbearing potential and nonvasectomized male subjects with a female partners of childbearing potential must agree that they and their partner will use effective contraception (two separate forms of contraception simultaneously, one of which must be a male condom with spermicide) from screening throughout the duration of study treatment and for at least 7 months

Exclusion criteria

• Pregnant women or women who may wish to become pregnant during the course of the study
• Male with a female who is pregnant or is planning to become pregnant within seven month the study of anticipated last dose of ribavirin
• Evidence of infection or co-infection with a no-genotype 1 HCV-strain
• History of hemoglobinopathy
• History of sarcoidosis
• History of invasive malignancy diagnosed or treated within 5 years.
• Untreated or significant psychiatric illnesses including severe depression, schizophrenia, psychosis, history of a suicide attempt
• Co-infection with HBV or HIV
• Chronic use of systemic immunosuppressive agents
• Presence of autoimmune disorders; subjects with treated hypothyroidism with normal TSH may be enrolled
• History of significant cardiac disease
• Clinical evidence of chronic pulmonary disease
• Known cirrhosis
• History of solid organ transplantation
• Suspicion of hepatocellular carcinoma
• Chronic liver disease of a non-HCV etiology
• Ongoing alcohol abuse
• History of clinical relevant drug abuse
• Positive urine screen for cocaine, opiate etc, or methadone use