Effect of indomethacin, aspirin, and acetaminophen on in vitro antiviral and antiproliferative activities of recombinant human interferon-alpha 2a.

The effects of indomethacin, aspirin, and acetaminophen on the antiviral and antiproliferative activities of recombinant human interferon-alpha 2a (rIFN-alpha 2a) were studied in vitro. None of the drugs inhibited the antiviral activity of rIFN-alpha 2a in human amnion FL cells against vesicular stomatitis virus, or interfered with its antiproliferative activity against acute lymphoblastic leukemia MOLT-4 cells or renal cell carcinoma NC 65 cells. Although, at high concentrations, aspirin (1 mM) or indomethacin (0.1 mM) alone inhibited the cell growth, rIFN-alpha 2a showed clear additive growth inhibition. It was concluded that neither indomethacin, aspirin, nor acetaminophen directly inhibited the antiviral and antiproliferative activities of rIFN-alpha 2a. The possible use of these three drugs to reduce the adverse effects of rIFN-alpha 2a without spoiling its profitable efficacy in clinical practice is suggested.