Hi,
So they say some hepb patient become resistant to drugs. They say it is because the virus has mutated to be resistant to the drugs.
So if this hep b patient infect another person can this person have the drug resistant virus so the drugs will not work on him also ?
Br,
Hi, I am not a doctor or a researcher. I will give you a layman view. If a person is infected by a HBV patient with a strain of HBV that is resistant to a certain anti-HBV drug, and if the person becomes chronic, it is very certain that the new HBV patient will also be resistant to that HBV drug. In adults, when infected, the virus must survive in a new environment, so the infected adult may not become chronic. If a drug targets the Hep B virus itself, then it is almost certain that the virus will develop resistance against that drug. However, if the drug targets the virus in several different ways (e.g. different sites in the Reverse Transcription region of the HBV polymerase gene), then it will take the virus a long time or never to become resistant to that drug. This is the case for Tenofovir and Entecavir. These drugs target more than one site in the RT region of the polymerase gene; and also because less virus production means less mutation. So, probability of Tenofovir resistance is very low. Also, if an antiviral drug becomes resistant, there are drug combinations that can overcome the resistance. The combination may involve drugs that target the Hep B virus differently, such as viral capsid’s formation, CAM, or drugs that target the translation of viral mRNA, such as siRNA, RNAi, or immunomodulatory drugs such as Interferons, NAPs to block HBsAg release, and even mono or multi-clonal HBsAb. Drug resistance is no longer a problem for HBV, today we concentrate on developing cheap drugs and a finite treatment resulting in a functional cure.
Dear @hepb1,
There is no evidence of widespread resistance to tenofovir or entecavir. The case you lay out was relatively common for older drugs like lamivudine (because of this it is now not recommended as a first-line treatment).There have been some cases of entecavir resistance in people, but it doesn’t seem to spread very well because of all the mutations that have to be made for it to happen. In any case, people with these viruses can successfully be treated with tenofovir.
Hope this helps,
Thomas