Analysis of HCV-specific T cell responses in patients treated with boceprevir to assess whether therapy can induce restoration of the T cell function and to what extent this recovery can be achieved

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

Naïve genotype 1 chronic hepatitis C patients