The first international standard for antibodies to HPV 16

► A candidate WHO 1st international standard for anti-HPV 16 serum was evaluated. ► The candidate 05/134 is freeze-dried serum from women naturally infected with HPV 16. ► For the study, 05/134 was assessed in a range of typical assays in 11 laboratories. ► 05/134 will facilitate the harmonization of anti-HPV 16 assays worldwide. ► WHO ECBS established 05/134 with an assigned potency of 5 IU per ampoule.