title: Effect of leflunomide and cidofovir on replication of BK virus in an in vitro culture system.
abstract: BACKGROUND
  Cidofovir and Leflunomide are used empirically in the treatment of BK virus nephropathy. The aim of this study is to quantify the antiviral activity of these drugs.
  
  
  METHODS
  BK virus was grown in a cell-culture system. The rate of viral replication in the presence or absence of the drug being tested was assessed using a quantitative polymerase chain reaction assay.
  
  
  RESULTS
  The inhibitory concentration, effective concentration, and selectivity index for Leflunomide are 39.7+/-6.9, 11.3+/-2.8, and 3.8+/-0.8 microg/mL, respectively. For Cidofovir, these indices were, respectively, 63.9+/-17.2, 36.3+/-11.7, and 2.3+/-0.8 microg/mL.
  
  
  CONCLUSIONS
  The in vitro activity of Cidofovir and Leflunomide is modest, and the selectivity index is low. There is a need to develop more effective and less toxic anti-BK virus drugs for clinical use.
authors.affiliation: Department of Pathology, University of Pittsburgh Medical Center, Pittsburgh, PA 15213, USA.
authors.forename: Noush Afarin
authors.initials: NA
authors.lastname: Farasati
authors.forename: Ron
authors.initials: R
authors.lastname: Shapiro
authors.forename: Abhay
authors.initials: A
authors.lastname: Vats
authors.forename: Parmjeet
authors.initials: P
authors.lastname: Randhawa
mesh_terms: D000998:Antiviral Agents / Q000494:pharmacology*; D001739:BK Virus / Q000187:drug effects* / Q000502:physiology; D000077404:Cidofovir; D003596:Cytosine / Q000031:analogs & derivatives* / Q000494:pharmacology*; D007555:Isoxazoles / Q000494:pharmacology*; D000077339:Leflunomide; D063065:Organophosphonates / Q000494:pharmacology*; D014779:Virus Replication / Q000187:drug effects*
chemical_list: D000998:Antiviral Agents; D007555:Isoxazoles; D063065:Organophosphonates; D003596:Cytosine; D000077339:Leflunomide; D000077404:Cidofovir