Abstract

We read the article published by Alagozlu et al. (2013) with interest. The authors found that 100% of chronic HBV patients who underwent antiviral therapy using either lamivudine/adefovir alone or in combination, contained either silent (24.4%) or missense (75.6%) mutations in their YMDD motif of HBV polymerase proteins. A variety of unusual silent mutations were found in the former group. Authors did not present the details for treatment regimen for patients group. Therefore, the mutation profiles in the text cannot be assigned to the type of drug-used. However, some comments deserve to mention. Interestingly, authors found a population of transitions/transversion nucleotide substitutions that might have some impacts on HBV combination therapy. Our unpublished data on Iranian genotype D patients (the same main genotype circulating in Turkey) confirms such hypothesis. We investigated the mutational profile for 3 similar groups as Alagozlu et al’s study (Mahabadi et al., 2013) . In Lamivudine-only group, we found F221Y/S and L229G which are related to adefovir (ADV) resistancy. W153Q, I169T, A200V and S202G which are related to Lamivudine-resistancy were found in ADV-only group. Finally, highest frequency of substitutions for residues L180M (43.7%) and M204I/V (68.7%) were found for Lamivudine/ADV combination group than all other groups. L217R and L229M/W were found in combination group. All of these patients showed partial resistance to these drugs, thus, they switched to other new anti-HBV nucleoside analogues regimen. Among 100 treatment-naive patients (control group), we found a variety of above mono/combination mutations in an average of 1-8%. Similarly, in another national-based retrospective study, 2.4 to 17.3% of treatment naive patients contained a cocktail of either mono- or combination related mutations;

Highlights

  • Taken together, we believe that a genotypic and/or phenotypic assay (s) should be performed before starting treatment for the chronic HBV patients who are candidate for therapy to identify the mutational profile of patients to avoid partial/typical resistance occurance

  • The authors found that 100% of chronic HBV patients who underwent antiviral therapy using either lamivudine/adefovir alone or in combination, contained either silent (24.4%) or missense (75.6%) mutations in their YMDD motif of HBV polymerase proteins

  • A variety of unusual silent mutations were found in the former group

Read more

Summary

Introduction

We believe that a genotypic and/or phenotypic assay (s) should be performed before starting treatment for the chronic HBV patients who are candidate for therapy to identify the mutational profile of patients to avoid partial/typical resistance occurance. We read the article published by Alagozlu et al (2013) with interest. The authors found that 100% of chronic HBV patients who underwent antiviral therapy using either lamivudine/adefovir alone or in combination, contained either silent (24.4%) or missense (75.6%) mutations in their YMDD motif of HBV polymerase proteins. A variety of unusual silent mutations were found in the former group.

Results
Conclusion

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.