Retrospective Study
Copyright ©The Author(s) 2017. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Mar 7, 2017; 23(9): 1618-1626
Published online Mar 7, 2017. doi: 10.3748/wjg.v23.i9.1618
Optimizing hepatitis C virus treatment through pharmacist interventions: Identification and management of drug-drug interactions
Jacob A Langness, Matthew Nguyen, Amanda Wieland, Gregory T Everson, Jennifer J Kiser
Jacob A Langness, Matthew Nguyen, Amanda Wieland, Gregory T Everson, Jennifer J Kiser, Hepatology and Transplant Clinic, University of Colorado Hospital, Aurora, CO 80045, United States
Jacob A Langness, Department of Pharmacy, University of Colorado Hospital, Aurora, CO 80045, United States
Matthew Nguyen, Jennifer J Kiser, University of Colorado Skaggs School of Pharmacy and Pharmaceutical Sciences, Aurora, CO 80045, United States
Amanda Wieland, Gregory T Everson, Department of Gastroenterology, School of Medicine, University of Colorado, Aurora, CO 80045, United States
Author contributions: Langness JA and Nguyen M contributed equally to this work; Wieland A, Everson GT and Kiser JJ contributed to the original project proposal and identification of key components; Kiser JJ is senior author and oversaw the initial proposal, design, statistical analysis and editing and formatting of manuscript; Langness JA and Nguyen M contributed to data collection, statistical analysis, and manuscript; Wieland A, Everson GT and Kiser JJ edited manuscript; all authors have read and approved final version to be published.
Institutional review board statement: This retrospective review was considered exempt by the Colorado Institutional Review Board since the research involves the study of existing data and all data was de-identified prior to analysis.
Informed consent statement: As this was a retrospective review that involved de-identified data and did not affect patient care. Therefore informed consent was not required.
Conflict-of-interest statement: Langness JA and Nguyen M have nothing to disclose. Wieland A receives grant funding from Janssen. Everson GT receives grant funding from Merck, Abbvie, Gilead, BMS, and Janssen and is on Ad Boards for Merck, Abbvie, Gilead, BMS, and Janssen. Everson GT has ownership and management of HepQuant LLC. Kiser JJ receives research support paid to her institution from ViiV Healthcare and free study medication for an NIH trial from Gilead Sciences.
Data sharing statement: Technical appendix, statistical code, and dataset available from the corresponding author at jennifer.kiser@ucdenver.edu. All data associated with this study are de-identified and no personal health information is available through the dataset.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Jennifer J Kiser, PhD, University of Colorado Skaggs School of Pharmacy and Pharmaceutical Sciences, Mail Stop C238, 12850 E. Montview Blvd. V20-4102 , Aurora, CO 80045, United States. jennifer.kiser@ucdenver.edu
Telephone: +1-303-7246131 Fax: +1-303-7246135
Received: October 21, 2016
Peer-review started: October 24, 2016
First decision: December 28, 2016
Revised: January 12, 2017
Accepted: February 6, 2017
Article in press: February 8, 2017
Published online: March 7, 2017
Processing time: 136 Days and 3.1 Hours
Abstract
AIM

To quantify drug-drug-interactions (DDIs) encountered in patients prescribed hepatitis C virus (HCV) treatment, the interventions made, and the time spent in this process.

METHODS

As standard of care, a clinical pharmacist screened for DDIs in patients prescribed direct acting antiviral (DAA) HCV treatment between November 2013 and July 2015 at the University of Colorado Hepatology Clinic. HCV regimens prescribed included ledipasvir/sofosbuvir (LDV/SOF), paritaprevir/ritonavir/ombitasvir/dasabuvir (OBV/PTV/r + DSV), simeprevir/sofosbuvir (SIM/SOF), and sofosbuvir/ribavirin (SOF/RBV). This retrospective analysis reviewed the work completed by the clinical pharmacist in order to measure the aims identified for the study. The number and type of DDIs identified were summarized with descriptive statistics.

RESULTS

Six hundred and sixty four patients (83.4% Caucasian, 57% male, average 56.7 years old) were identified; 369 for LDV/SOF, 48 for OBV/PTV/r + DSV, 114 for SIM/SOF, and 133 for SOF/RBV. Fifty-one point five per cent of patients were cirrhotic. Overall, 5217 medications were reviewed (7.86 medications per patient) and 781 interactions identified (1.18 interactions per patient). The number of interactions were fewest for SOF/RBV (0.17 interactions per patient) and highest for OBV/PTV/r + DSV (2.48 interactions per patient). LDV/SOF and SIM/SOF had similar number of interactions (1.28 and 1.48 interactions per patient, respectively). Gastric acid modifiers and vitamin/herbal supplements commonly caused interactions with LDV/SOF. Hypertensive agents, analgesics, and psychiatric medications frequently caused interactions with OBV/PTV/r + DSV and SIM/SOF. To manage these interactions, the pharmacists most often recommended discontinuing the medication (28.9%), increasing monitoring for toxicities (24.1%), or separating administration times (18.2%). The pharmacist chart review for each patient usually took approximately 30 min, with additional time for more complex patients.

CONCLUSION

DDIs are common with HCV medications and management can require medication adjustments and increased monitoring. An interdisciplinary team including a clinical pharmacist can optimize patient care.

Keywords: Clinical pharmacist; Drug-drug interaction; Hepatitis C virus treatment

Core tip: Identification and management of potential drug-drug interactions (DDI) is a critical aspect of current hepatitis C virus (HCV) treatment. This retrospective analysis of patients prescribed common HCV treatments identifies DDIs and the interventions made by the clinical pharmacist, as well as the approximate time required to complete these activities. This novel review illustrates that DDIs are common in this population. Identification and management of DDIs is resource intensive and requires medication adjustments and increased monitoring. An interdisciplinary care team including a clinical pharmacist is critical to optimize patient care for new HCV therapies.