|The Y181C Mutation
Aug 19, 2006
Dear Drs. Is the Y181C mutation that showed up 7 years ago after taken viramune that does not appear on a genotype done today rule out sustiva as a drug option? Thank you.
Response from Dr. Young
Thanks for your post.
In general resistance to one NNRTI [in your case, selected by nevirapine (Viramune) and evidenced by the Y181C mutation] confers resistance to other NNRTIs, like efavirenz (Sustiva). For this reason, if you've had previous failure of a nevirapine regimen, you shouldn't take efavirenz, especially if you have other treatment options.
The fact that the resistance mutation is no longer detected doesn't mean that the resistant virus isn't there, rather in the absence of either NNRTI, it's just present (or archived) at levels lower than the resistance test can detect. Once the virus population in your body becomes "challenged" by NNRTI, the resistance virus will readily grow (compared with the wild type, drug sensitive virus).
Hope this helps. BY
DO I NEED NEW MEDS?
This forum is designed for educational purposes only, and experts are not rendering medical, mental health, legal or other professional advice or services. If you have or suspect you may have a medical, mental health, legal or other problem that requires advice, consult your own caregiver, attorney or other qualified professional.
Experts appearing on this page are independent and are solely responsible for editing and fact-checking their material. Neither TheBody.com nor any advertiser is the publisher or speaker of posted visitors' questions or the experts' material.