Supersensitive Viral Load Assay in Predicting CD4-Guided Treatment Failure

Simone Langforda, §, Angele Gayet-Ageronb, §, Chris Duncombea, Thidarat Jupimaia, Apicha Mahanontharita, Sasisopin Kiertiburanakulc, Warangkana Munsakuld, Kiat Ruxrungthama, e, Bernard Hirschelb, Jintanat Ananworanich*, a, f, Staccato Study Group
a The HIV Netherlands Australia Thailand Research Collaboration (HIV-NAT), Bangkok, Thailand
b HIV Unit, Infectious Disease Department, Geneva University Hospital, Geneva, Switzerland
c Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand
d Bangkok Metropolitan Administration Medical College and Vajira Hospital, Bangkok, Thailand
e Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
f South East Asia Research Collaboration with Hawaii, Bangkok, Thailand

© Langford et al.; Licensee Bentham Open.

open-access license: This is an open access article licensed under the terms of the Creative Commons Attribution Non-Commercial License ( which permits unrestricted, non-commercial use, distribution and reproduction in any medium, provided the work is properly cited.

* Address correspondence to this author at the HIV Netherlands Australia Thailand Research Collaboration (HIV-NAT), 104 Rajdumri Road, Pathumwan, Bangkok 10330, Thailand; Tel: +66-2-255-7335, Ext. 129; Fax: +66-2-252-5779; E-mail:
§ These Authors Contributed Equally


In HIV patients who discontinue highly active antiretroviral therapy (HAART), the degree of HIV RNA suppression at the time of treatment interruption may predict success of re-treatment after the interruption (STI). A case-control substudy of the Staccato trial in Thailand included CD4-guided STI subjects with HIV RNA > 50 copies /ml (virological failure cases, n=11) and HIV RNA < 50 copies/ml (controls, n=22) after 12-24 weeks of HAART re-treatment following a median of 2 STI cycles. Controls were matched for age, gender and pre-ART CD4 count. HIV RNA with 5 copies/ml detection limit was determined on pre-virological failure samples. HIV RNA increased in cases compared to controls with each successive STI cycle (p-trend across time-points 0.004). The last HIV RNA below 50 copies/ml was significantly higher among cases compared to controls (p=.004). Measuring HIV RNA below 50 copies/ml may be useful in predicting virological failure to STI.