The Boceprevir and Sildenafil Pharmacokinetics Study
Condition: Hepatitis C
MeSH terms: Hepatitis C
Study type: Interventional
Phase: Phase 1

Summary: 
      This is a healthy volunteer study looking at the interactions between two drugs: boceprevir
      and sildenafil.

      New drugs are being developed to treat people with the chronic viral infection hepatitis C.
      Very little is know how these new treatments interact with other medications such as the
      drugs used to treat erectile dysfunction.

      The purpose of this study is to look at levels of both a new hepatitis C drug called
      boceprevir (BOC) and an existing erectile dysfunction drug called sildenafil to see if they
      affect the blood levels of each other when given separately and together.
    

Detailed description: 
      Total duration for each participant will be up to 40 days plus a screening visit 1 - 3 weeks
      prior to the start of the study.

      They will visit the clinic on 10 occasions: screening visit, baseline visit (day 0), day 1, a
      visit between day 4 and 7, day 10, day 14, day 15, day 16, day 17 and a follow up visit
      between days 26 and 40.

      The total amount of blood collected from participants during the entire study will be no
      greater than 350 ml in total (around 23 tablespoons).

      At the screening visit a clinical assessment will be performed. At the baseline visit
      participants will attend the clinic fasted and will be required to remain on the unit for
      approximately 14 hours.

      On the morning of the visit clinical assessments will be performed. Sildenafil 25mg (1
      tablet) will be administered with a standardised meal. Blood samples will be taken at the
      following times in order to measure the levels of sildenafil in the blood: predose,0.5, 1, 2,
      3, 4, 6, 8, 10,12 and 24 hours post dose.

      On day Day 10 boceprevir will be initiated 800mg (4 capsules 3 times a day) for the next 4
      days on day 14 the participants will attend the clinic for a witnessed dose of boceprevir and
      safety assessment.

      On day 15 the participants will attend for their 2nd long visit (10 hours) when they will be
      administered boceprevir (BOC) 800mg (4 capsules) with a standardised meal then have blood
      samples taken at the following times in order to measure the levels of BOC in the blood:
      predose,0.5, 1, 2, 3, 4, 6 and 8 hours post dose.

      After the 8 hour blood collection participants will be administered boceprevir (BOC) 800mg (4
      capsules) with food and they will self administer BOC 800mg (4 capsules) with food at home 8
      hours later.

      On day 16 participants will attend for the 3rd long visit (14 hours) where they will be
      administered boceprevir (BOC) 800mg (4 capsules) and sildenafil 25mg with a standardised
      meal. Blood samples will be taken at the following times in order to measure the levels of
      both BOC and sildenafil in the blood: predose,0.5, 1, 2, 3, 4, 6 and 8 hours post dose.

      After the 8 hour blood collection participants will be administered boceprevir (BOC) 800mg (4
      capsules) with food and will then self administer BOC 800mg (4 capsules) with food at home 8
      hours later. This will be their last dose of study medication. They will return the next day
      for a final blood test post 24 hours. A final visit between days 26 and 40 will be performed
      including clinical assessments.
    

Intervention name(s): Sildenafil and Boceprevir
Intervention type(s): Drug
Intervention description(s): 25mg once/800mg three times a day
Other intervention name(s): Viagra and Victrelis
Intervention MeSH terms: Sildenafil Citrate
Intervention model: Single Group Assignment
Masking: None (Open Label)
Primary purpose: Treatment
Keywords: Healthy volunteers