title: A new tool to study ribavirin-induced haemolysis.
abstract: BACKGROUND
  Today, treatment of chronic hepatitis C is based on a synergistic combination of pegylated interferon and ribavirin with antiprotease inhibitors. Haemolytic anaemia, which is the major side effect of ribavirin treatment, disrupts ribavirin treatment compliance and varies significantly from one patient to another. There is an individual susceptibility to ribavirin haemolysis. With a view to studying haemolysis, and thus optimizing the treatment response, we have developed a new in vitro tool for analysing the ribavirin-induced lysis of red blood cells.
  
  
  METHODS
  Resuspended red blood cells were incubated with isotonic buffer and a range of concentrations of ribavirin. Haemolysis was quantified by spectrophotometric measurement of the supernatant at 540 nm. The assay was used to test the effects of various compounds and to investigate the susceptibility of patients to haemolytic anaemia.
  
  
  RESULTS
  In our assay, the degree of haemolysis is dependent on the ribavirin concentration used and can be inhibited by the addition of dipyridamole (50% inhibitory concentration [IC(50)] 30 μM), ATP or glutathione (IC(50) 1.63 mM and 767 μM, respectively). We observed a strong decrease in red blood cell haemolysis in the presence of the ribavirin prodrug viramidine (Taribavirin(®)). When testing the performance of this assay with blood from 24 patients before treatment, we observed a strong correlation between in vitro haemolysis before treatment and the decrease in haemoglobin levels seen in vivo during subsequent treatment (P<0.001).
  
  
  CONCLUSIONS
  With this new tool it is possible to better evaluate individual susceptibility to ribavirin-induced haemolysis before the start of treatment. In addition, this model will enable the mechanism of ribavirin-induced anaemia to be further explored and allow molecules that could reduce ribavirin haemolysis to be screened and tested in vitro. This approach could help optimize current and future therapeutic strategies involving ribavirin in the treatment of chronic hepatitis C.
authors.affiliation: Department of Virology, Amiens University Medical Center, Amiens, France. etienne.brochot@u-picardie.fr
authors.forename: Etienne
authors.initials: E
authors.lastname: Brochot
authors.forename: Catherine
authors.initials: C
authors.lastname: François
authors.forename: Sandrine
authors.initials: S
authors.lastname: Castelain
authors.forename: François
authors.initials: F
authors.lastname: Helle
authors.forename: Albert Nguyen
authors.initials: AN
authors.lastname: Van Nhien
authors.forename: Isabelle
authors.initials: I
authors.lastname: Duchaussoy
authors.forename: Dominique
authors.initials: D
authors.lastname: Capron
authors.forename: Eric
authors.initials: E
authors.lastname: Nguyen-Khac
authors.forename: Gilles
authors.initials: G
authors.lastname: Duverlie
mesh_terms: D000255:Adenosine Triphosphate / Q000494:pharmacology; D000328:Adult; D000743:Anemia, Hemolytic / Q000139:chemically induced / Q000473:pathology; D004176:Dipyridamole / Q000494:pharmacology; D004353:Drug Evaluation, Preclinical; D004359:Drug Therapy, Combination; D004912:Erythrocytes / Q000187:drug effects*; D005978:Glutathione / Q000494:pharmacology; D006403:Hematologic Tests / Q000379:methods; D006461:Hemolysis; D016174:Hepacivirus / Q000235:genetics / Q000472:pathogenicity; D019698:Hepatitis C, Chronic / Q000188:drug therapy / Q000821:virology; D006801:Humans; D020128:Inhibitory Concentration 50; D000077190:Interferon alpha-2; D016898:Interferon-alpha / Q000008:administration & dosage / Q000494:pharmacology; D017955:Poliovirus / Q000187:drug effects; D011092:Polyethylene Glycols / Q000008:administration & dosage / Q000494:pharmacology; D011355:Prodrugs / Q000494:pharmacology; D012367:RNA, Viral / Q000097:blood; D011994:Recombinant Proteins / Q000008:administration & dosage / Q000494:pharmacology; D012254:Ribavirin / Q000008:administration & dosage / Q000009:adverse effects* / Q000031:analogs & derivatives / Q000494:pharmacology / Q000627:therapeutic use
chemical_list: D000077190:Interferon alpha-2; D016898:Interferon-alpha; D011355:Prodrugs; D012367:RNA, Viral; D011994:Recombinant Proteins; D011092:Polyethylene Glycols; D012254:Ribavirin; D004176:Dipyridamole; D000255:Adenosine Triphosphate; C417083:peginterferon alfa-2b; D005978:Glutathione; C026956:taribavirin