An in vitro analysis of the interaction between infliximab and granulocyte–monocyte apheresis

Abstract

ObjectivePrimary non-response and secondary loss of response to anti-TNF agents are common in inflammatory bowel disease. Increasing drug concentrations are correlated to better clinical response and remission rates. Combination of granulocyte–monocyte apheresis (GMA) with anti-tumor necrosis factor (TNF) agents could be an option in these patients. The objective of our study was to perform an in vitro assay to determine if the GMA device can lead to infliximab (IFX) adsorption. Patients and methodsA blood sample was obtained from a healthy control. It was incubated with three concentrations of IFX (3, 6, and 9μg/ml) at room temperature for 10min. At that time, 1ml was collected to determine the IFX concentration. Then, 10ml of each drug concentration was incubated with 5ml of cellulose acetate (CA) beads from the GMA device at 200rpm for 1h at 37°C to simulate physiological human conditions. A second sample of each concentration was collected and IFX levels were determined. ResultsNo statistically significant differences were observed in the IFX levels in the blood samples before and after incubation with the CA beads (p=0.41) and after repeated measurements (p=0.31). Mean change was 3.8μg/ml. ConclusionsThe in vitro combination of GMA and IFX did not change the circulating levels of IFX at the three concentrations tested, suggesting that there is no interaction between the drug and the apheresis device in vitro and that they might be safely combined with each other.