Short summary

Hepatitis C treatment is now going through a revolution after the introduction of the new drugs, Direct-Acting Antivirals (DAA), with cure rates more than 90% after 3 months of treatment. It is only a matter of time and money when hepatitis C no longer poses a significant health problem in Denmark.

However, there are significant drug- drug interaction (DDI) between DAA and the other medicines that the patients take (co-medication). The extent and importance of these interactions are not well documented in current literature.

Rationale

For many years pegylated interferon-alfa (pegIFN) has been the backbone of chronic Hepatitis C (CHC) treatment. In the last couple of years, the treatment regime has increased enormously with the introduction of Direct Acting Antivirals (DAAs) with higher cure rates now up to 95% after 8-12 weeks of treatment in most cases. Furthermore fewer side effects and better tolerability are seen during treatment with these drugs compared to the previously used interferon and ribavirin treatment. An effective well-tolerated treatment for all infected is an important step towards achieving WHO's goal for viral hepatitis, which aims at 90% reduction of incidence rate  and 65% reduction of mortality rate in 2030.

DAA treatment is a combination of several different drug groups (protease inhibitor, NS5A inhibitor and polymerase inhibitor) that can be combined with ribavirin, dependent on viral genotype, presence of cirrhosis and comorbidity. This gives rise to significant interaction possibilities between DAA and co-medications.

A master's thesis was done in the spring of 2017 by 2 pharmacy students with record linking of treatment and prescription data (OPED) with a view to identification of interactions between DAA and given medication. However, that thesis did not provide insight into the patient-experienced side effects, and if the interactions required change in patient medication or discontinuation of DAA treatment.

This thesis extends the data set with patient journal information and information on adverse reactions and changes made in medication during the treatment due to interaction (potential) or (severe) adverse events.

The aim of this thesis is to identify these (severe) adverts events, art and frequency as well as the changes made in medication as a consequence.

Description of the cohort

Retrospective cohort study with 127 hepatitis C patients treated  with DAA at the Department  of Infectious  Diseases at Odense University Hospital (OUH) in period  01.01.2014 - 31.12.2016.

Data and biological material

Relevant database such  as patient journals (cosmic), Infcare database, data set from a previous master thesis.