Key clinical point: Treatment of irradiated peripheral blood mononuclear cells (PBMCs) with filgotinib in particular correlated with enhanced foci in vitro; the study was a rare comparison of all four JAKis approved for RA: tofacitinib, baricitinib, and upadacitinib, and filgotinib.
Major finding: Lymphocyte proliferation was similar for tofacitinib, baricitinib, and upadacitinib, while dosage of filgotinib was two orders of magnitude higher when these JAKis were added to peripheral blood mononuclear cells from healthy donors.
Study details: The data come from an in vitro study of four JAK inhibitors currently approved for the treatment of RA: tofacitinib, baricitinib, upadacitinib, and filgotinib, in which increasing concentrations of the JAKis or methotrexate were added to peripheral blood mononuclear cells from healthy volunteers.
Disclosures: The study was supported by the European Union Program Regional Development Fund of the Ministry of Economy, Science and Digitalisation in Saxony-Anhalt. Lead author Dr. Reddig had no financial conflicts to disclose.
Source: Reddig A et al. J Clin Med. 2021 Apr 1. doi: 103390/jcm10071431.