Transmitted Drug Resistance
Mutations Among
Antiretroviral-naïve Adult
Patients In Northern Vietnam
Vu Phuong Thao, PhD
Oxford University Clinical Research Unit
Ho Chi Minh City, Viet Nam
Asia Pacific Aids & Co-infections Conference 2016
HIV epidemic in Vietnam
Estimated 280,000 people
HIV prevalence: 0.5%
+ IDU: 9.3%
+ FSW: 2.7%
+ MSM: 5.2%
Antiretroviral Therapy in Vietnam
2003
2005
CD4<200
2009
2011
CD4<350
2015
CD4<500
ARV resistance prior treatment in Vietnam
Study group
Stage of infection
Sample
size
2001-2002 HCMC
CSW, IDU, and
STD patients
chronic infection
200
200/200
13 (6.5%)
2006
VCT attendees
proxy recent infection
63
63/63
2 (3.2%)
2005-2007 HCMC
TBM co-infected
patients
chronic infection
219
218/218
14 (6.4%)
2006
Ha Noi
VCT attendees
proxy recent infection
70
49/49
1 (<5%)
2007
Hai Phong
CSW, IDU,
pregnant women, chronic infection
blood donor
301
273/294
8 (2.9%)
2008
Northern Vietnam
chronic infection
206
155/173
10 (6.5%)
2008-2009
Northern and
Southern Vietnam
chronic infection
122
92/92
7 (7.6%)
Year
Location
HCMC
CSW, IDU
Genotypes Prevalence
(RT/PR)
of HIV TDR
Objective
To investigate the prevalence, patterns and
risk factors of TDR among ART-naïve
patients starting ART in northern Vietnam
Study design
• Study population: Adult patients enrolling into the Viral Load
Monitoring RCT at Bach Mai Hospital in Hanoi from 04/2011
to 04/2014
• Resistance assessment:
o Population sequencing
o 2009 WHO Surveillance of Drug Resistance Mutations
• Statistical analyses
o Risk of TDR was evaluated using logistic regression
modeling. Predefined variables include: IDU, HBV or
HCV co-infection, baseline CD4 and HIV RNA
Results – Charactersitics of 388 patients
Characteristics
N=388
Male (%)
256 (82%)
Median age (years)
34 (29-39)
Median CD4 count (cells/mm3)
98 (32-258)
Median HIV RNA (log10 copies/mL)
5.2 (4.7-5.6)
Transmission route (%)
Injection drug user
Sexual transmission
Others
69 (18%)
303 (78%)
16 (4%)
Hepatitis co-infection (%)
HBSAg pos
Anti HCV
48 (12%)
144 (37%)
Identified TDR mutations by ARV class
SDRM detected in 24 patients (6.2%)
NRTI mutations: 13 patients (3.4%)
NNRTI mutations: 9 patients (2.3%)
Both NRTI and NNRTI: 3 patients
PI mutations: 5 patients (1.3%)
Results – risk factors of TDR
Patients
without
TDR
(N=364)
Patients
with TDR
(N=24)
IDU
65 (18%)
Median CD4
Covariates
Univariate effect
Multivariate effect
OR
(95% CI)
p-value
OR
(95% CI)
pvalue
4 (17%)
0.93
(0.26-2.53)
0.883
0.73
(0.19-2.37)
0.619
103
(31-262)
49
(22-222)
0.97
(0.82-1.13)
0.715
0.88
(0.60-1.23)
0.514
Median log10
HIV RNA
5.2
(4.7-5.6)
5.1
(4.3-5.6)
0.82
(0.48-1.43)
0.465
0.73
(0.40-1.38)
0.308
HBV or HCV
infection
154
(42%)
12
(50%)
1.36
(0.59-3.15)
0.462
1.48
(0.56-3.77)
0.413
Limitations
• Over-estimation of TDR due to self-reported ART
history
• Under-estimation of TDR due to:
o population of chronically HIV-infected patients
o limitation of Sanger sequencing method
• Not WHO recommended population for TDR
surveillance
Conclusions
• Prevalence of TDR in treatment-naïve adults initiating ART in
Hanoi remains at 5-10% level despite the continued scale up
of ART in Vietnam
• The identified RTI resistance mutations reflect the use of
NRTI/NNRTI as standard first-line. The identification of PI
resistance mutations reflects the history of IDV use and raises
a concern as PI is the last treatment option in Vietnam