JVI Figure table search 04
Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Eastman, P. S.
Right arrow Articles by Markowitz, M.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Eastman, P. S.
Right arrow Articles by Markowitz, M.

 Previous Article  |  Next Article 

J Virol, June 1998, p. 5154-5164, Vol. 72, No. 6
0022-538X/98/$04.00+0
Copyright © 1998, American Society for Microbiology. All rights reserved.

Genotypic Changes in Human Immunodeficiency Virus Type 1 Associated with Loss of Suppression of Plasma Viral RNA Levels in Subjects Treated with Ritonavir (Norvir) Monotherapy

P. Scott Eastman,1,* John Mittler,2 Reed Kelso,1 Chris Gee,1 Eric Boyer,1 Janice Kolberg,1 Mickey Urdea,1 John M. Leonard,3 Daniel W. Norbeck,4 Hongmei Mo,5 and Martin Markowitz5

Chiron Corporation, Emeryville, California 946081; Theoretical Biology and Biophysics and Center for Nonlinear Studies, Los Alamos National Laboratory, Los Alamos, New Mexico 875452; Pharmaceutical Products Division3 and Anti-Infective Research,4 Abbott Laboratories, Abbott Park, Illinois 60064; and Aaron Diamond AIDS Research Center, New York University School of Medicine, New York, New York 100165

Received 10 March 1997/Accepted 18 February 1998

Ten subjects received 600 to 1,200 mg of the human immunodeficiency virus type 1 (HIV-1) protease inhibitor ritonavir per day. Following 2 weeks of therapy, plasma HIV RNA levels decreased by a mean of 1.57 (range, 0.89 to 1.96) log units. With continued therapy, HIV RNA levels began to rise in eight subjects. The initial rise in plasma RNA levels was temporally associated with the development and quantitative increase in the V82 resistance mutation. Doubling times of the V82A mutant virus were estimated to be 2.4 to 4.8 days. An L63P/A mutation was commonly present at baseline even in subjects with a durable virologic response. The concomitant acquisition of an L63P/A mutation with the V82A/F mutation at the time when plasma RNA levels rebounded suggests a role for the L63P/A mutation in improving the fitness of the V82A/F mutation. Subsequent additional genotypic changes at codons 54 and 84 were often associated with further increases in plasma RNA levels. Ongoing viral replication in the presence of drugs resulted in the appearance of additional genotypic changes, including the L90M saquinavir resistance mutation, and decreased phenotypic susceptibility. The relative fitness of the protease V82A ritonavir resistance mutation and reverse transcriptase T215Y/F zidovudine resistance mutation following drug withdrawal were estimated to be 96 to 98% that of the wild type. Durability of the virologic response was associated with plasma RNA levels at the nadir. A virologic response beyond 60 days was not observed unless plasma HIV RNA levels were suppressed below 2,000 copies/ml, consistent with estimates from V82A doubling times for selection of a single resistance mutation to dominate the replicating population.

* Corresponding author. Mailing address: Chiron Corporation, 4560 Horton St., Emeryville, CA 94608. Phone: (510) 601-3048. Fax: (510) 655-7733. E-mail address: scott_eastman{at}cc.chiron.com.

J Virol, June 1998, p. 5154-5164, Vol. 72, No. 6
0022-538X/98/$04.00+0
Copyright © 1998, American Society for Microbiology. All rights reserved.


This article has been cited by other articles:



Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
J. Bacteriol. Mol. Cell. Biol. Microbiol. Mol. Biol. Rev.
Clin. Vaccine Immunol. ALL ASM JOURNALS

Copyright © 1998 by the American Society for Microbiology. All rights reserved.