1Division of Gastroenterology and Hepatology, UNC School of Medicine, Chapel Hill, NC, USA.
2Department of Biostatistics, Yale University School of Public Health, New Haven, CT, USA.
3United Therapeutic Corporation, Research Triangle Park, NC, USA.
Pegylated interferon-2a (PegIFN-2a)+ribavirin treatment for chronic hepatitis C is often associated with depressive symptoms. Previous studies have failed to explore whether PegIFN-2a pharmacokinetic variability plays an etiologic role in PegIFN-2a-induced mood disorders. The objective of this investigation was to evaluate the association between trough PegIFN-2a concentration at treatment week 4 ("PegIFN-2a Cmin4") and an increase in depressive symptoms.
Using data from Virahep-C, the association between PegIFN-2a Cmin4 and the following depression outcomes were evaluated using the Center for Epidemiological Studies-Depression scale (CES-D): (1) change in CES-D score from baseline to week 12; (2) greatest difference in CES-D score between baseline and weeks 4, 12, or 24; and (3) occurrence of severe depressive symptoms (CES-D greater than 23) at weeks 4, 12, or 24. One post-hoc analysis examined whether PegIFN-2a exposure during the first week of treatment was associated with change in CES-D score from baseline to week 4.
No significant associations between PegIFN-2a Cmin4 and the depression outcomes were observed (p>0.05). Exploratory analyses suggest a possible relationship between PegIFN-2a exposure during the first week of therapy and CES-D score change from baseline to week 4 (p=0.03).
PegIFN-2a concentration levels from baseline to week 4 do not predict the onset and severity of depressive symptoms during 24 weeks of antiviral therapy; however PegIFN-2a levels during the first week of treatment may predict depressive symptoms in the first 4 weeks, earlier than anticipated and warrants further exploration.