Johan Vingerhoets, Ilse Van Dromme, Wilbert van Duijnhoven, David Anderson, Sandra De Meyer, Lorant Leopold
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引用次数: 0
Abstract
Background: Pimodivir is a first-in-class polymerase basic protein 2 (PB2) subunit inhibitor of the influenza A polymerase complex. The randomized double-blinded placebo-controlled phase 2b TOPAZ study demonstrated antiviral activity and safety of twice daily pimodivir alone (300 mg, 600 mg) or in combination with oseltamivir (pimodivir 600 mg, oseltamivir 75 mg) in adult study participants with acute uncomplicated influenza A. The detailed genotypic and phenotypic characterization of viral variants observed in this study are reported.
Methods: Population sequencing of PB2 and neuraminidase genes, and phenotypic susceptibility testing, were performed using baseline and last virus-positive post-baseline nasal swab samples.
Results: Sequencing of baseline samples in 206 of 223 (92.4%) randomized study participants with confirmed influenza A infection identified no polymorphisms at any predefined PB2 positions of interest for pimodivir and no phenotypic reduced susceptibility to pimodivir was observed. Post-baseline sequencing data for 105/223 (47.1%) participants identified emergence of PB2 mutations at amino acid positions of interest in 10 (9.5%) participants (pimodivir 300 mg: n = 3; 600 mg: n = 6; combination: n = 1; placebo: n = 0) and included positions S324, F325, S337, K376, T378, and N510. These emerging mutations were typically associated with decreased pimodivir susceptibility, but not viral breakthrough. No reduced phenotypic susceptibility was observed in the one (1.8%) participant with emerging PB2 mutations from the pimodivir plus oseltamivir group.
Conclusions: Participants with acute uncomplicated influenza A treated with pimodivir in the TOPAZ study infrequently developed reduced susceptibility to pimodivir and combining pimodivir with oseltamivir further decreased the risk of reduced susceptibility development.
期刊介绍:
Antiviral Therapy (an official publication of the International Society of Antiviral Research) is an international, peer-reviewed journal devoted to publishing articles on the clinical development and use of antiviral agents and vaccines, and the treatment of all viral diseases. Antiviral Therapy is one of the leading journals in virology and infectious diseases.
The journal is comprehensive, and publishes articles concerning all clinical aspects of antiviral therapy. It features editorials, original research papers, specially commissioned review articles, letters and book reviews. The journal is aimed at physicians and specialists interested in clinical and basic research.