THE 6TH
NATIONAL SCIENTIFIC CONFERENCE ON HIV/AIDS
The acquired HIV drug resistance
among HIV adults receiving ART
at least 36 months in Vietnam
Vũ Quốc Đạt1, Đỗ Thị Nhàn2, Nguyễn Hữu Hải2, Trương Thị Xuân Liên3, Nguyễn Thị Lan Anh4,
Huỳnh Hoàng Khánh Thư3, Nguyễn Trần Hiển4, Lương Quế Anh3, Dương Thị Thu Thủy4, Đỗ Thị Ngọc Thảo3,
Tạ Thị Thu Hồng4, Nguyễn Vũ Thượng3, Đỗ Huy Dương4, Trần Phúc Hậu3, Khưu Văn Nghĩa3,
Nguyễn Duy Phúc3, Phạm Thị Minh Hằng3, Nguyễn Thị Thúy Vân5, Bùi Đức Dương2, Masaya Kato5
1
Hanoi Medical University (HMU)
2
Viet Nam Administration of HIV/AIDS Control (VAAC)
3
Pasteur Institute (PI) – Ho Chi Minh city
4
National Institute of Hygiene and Epidemiology (NIHE)
5
World Health Organisation (WHO)
Outline
1. Background
2. Objectives
3. Methods
4. Results & Discussions
5. Conclusions
The 6th National Scientific Conference on HIV/AIDS
Background
• The surveillance of acquired drug resistance is
essential in context of rapid ART scaling up.
• The study aims to estimate representative
prevalence of viral load suppression and HIV
drug resistance among individuals who started
ART ≥ 36 months in Vietnam.
The 6th National Scientific Conference on HIV/AIDS
Objectives
• 1. Prevalence of viral load suppression (VL<1000 copies/mL) among
individuals sampled who have been on ART ≥ 36 months
– Prevalence of viral load suppression (VL<1000 copies/mL) among
individuals sampled who have been on first-line ART ≥ 36 months
• 2. Prevalence of HIV drug resistance among individuals sampled
who have been on ART ≥ 36 months
• 3. Prevalence of HIV drug resistance among individuals sampled
with viral load >1000 copies/mL who have been on ART ≥36 months
– Prevalence of HIV drug resistance among individuals sampled with viral
load >1000 copies/mL who have been on first-line ART ≥ 36 months
The 6th National Scientific Conference on HIV/AIDS
Survey Population
• Participant inclusion criteria
– HIV (+) Individuals who provide informed consent
– Adults who are 18 years of age or older who have
been on ART for at least 36 months at the time of
clinic visit, regardless of site of therapy initiation.
• Participant exclusion criteria
– Individuals with HIV-2 or HIV-1/HIV-2 co-infection, if
information available
The 6th National Scientific Conference on HIV/AIDS
Methods
• A cross-sectional surveys using cluster sampling
• The sampling frame is the list of all adult ART clinics in
Vietnam by the end of 2010 where patients receiving ART
•
Probability proportional to proxy size (PPPS) sampling
– A likely proxy is the total eligible number of patients on ART for ≥ 36
months at each clinic that as of December 2010.
– This number of patients is proxy population size will be used for
sampling.
– In PPPS sampling, the probability that a clinic is sampled is
proportional to the size of the proxy patient population.
The 6th National Scientific Conference on HIV/AIDS
Methods
• We planed to sample n=16 clinics without
stratification assumes that prevalence of viral
load suppression of 70% for the 36+ month time
point, and desires a confidence interval length of
±7%, assume laboratory failure rate of 15%
• The actual sample size of 368
The 6th National Scientific Conference on HIV/AIDS
Methods
• Until 12/2010, there was total of 217 ART clinics with 48.606
patients on ART by 2010 throughout Vietnam
• Sampling frame consist of 216 eligible clinics, exclude:
– 9 pediatric ART clinics
– 4 military ART clinics and 3 interim ART offices under Department of
Labor, War Invalids and Social Affairs without tracking system
(consists of 494 patients)
• To enhance the geographic representativeness of the sample,
clinics are listed by geographic area before using systematic
sampling for generating probability proportional to size sample
The 6th National Scientific Conference on HIV/AIDS
Study locations
Name of OPC
Name of
province
No. of active ART
pts by end of 2010
Region
Level
Required
sample
OPC of Health Center, Thanh hoa city
Thanh Hoa
395
Mid
District
23
Quang Ninh Provincial Hospital OPC
Quang Ninh
984
North
Provincial
23
Dong Da hospital OPC
Ha Noi
583
North
District
23
Yen Bai provincial hospital OPC
Yen Bai
478
North
Provincial
23
Quang Ninh
330
North
National
23
Ha Noi
250
North
District
23
Thai Nguyen
178
North
Provincial
23
Health Center, Thanh Xuan district OPC
Ha Noi
101
North
District
23
Tropical Diseases Hospital
HCMC
3334
South
Provincial
23
Binh Thanh district OPC
HCMC
1146
South
District
23
District 6 OPC
HCMC
1033
South
District
23
District 2 OPC
HCMC
963
South
District
23
Phu Nhuan preventive medicine center OPC
HCMC
530
South
District
23
Dong Thap Provincial AIDS prevention center
Dong Thap
386
South
Provincial
23
Vinh Long provincial hospital OPC
Vinh Long
322
South
Provincial
23
Kien Giang provincial hospital OPC
Kien Giang
180
South
Provincial
23
Vietnam-Sweden Friendship Hospital, Uong Bi OPC
Health Center, Tu Liem district OPC
OPC of the Health Center, Thai Nguyen city
TOTAL
368
The 6th National Scientific Conference on HIV/AIDS
Methods
• Specimens with a VL of ≥1000 copies/mL were genotyped to
determine HIVDR status in the two laboratories accredited by
WHO for National HIV Drug Resistance laboratory (NIHE and
Pasteur Institute).
• HIVDR genotypic test was conducted on pol gene with the
ABI 3130XL system using the Big-Dye Terminator v3.1 Cycle
Sequencing Kit (Applied Biosystem, California, USA).
• HIVDR was interpreted with the HIValg program in the
Stanford HIV drug resistance database.
The 6th National Scientific Conference on HIV/AIDS
Results
• A total of 368 patients with HIV was recruited from
16 clinics throughout the country.
– Three were excluded because of the violation of the
inclusion criteria of ART duration of at least 36 months.
• The final number of 365 PLHIV was eligible for
analysis
– 365 patients receiving viral load testing
– 20 patients failure to viral load suppression
– 19 patients with any drug mutation
The 6th National Scientific Conference on HIV/AIDS
Results
Characteristic of study population
Characteristic
N
All participants
Age in years (CI95%)
Sex
Male
Female
HIV risk exposure
Injecting drug use
Heterosexual
Homosexual
Others or unknown
Length of ART
Median (IQR)
36 month - 47 months
48 months - 71 months
≥ 72 months
Total sampled patients
N
Pts with any mutation
365
365
38.0 (37.3 - 38.7)
19
19
38.1 (35.4 -40.7)
247
118
67.7%
32.3%
13
6
68.4%
31.6%
141
201
1
22
38.6%
55.1%
0.3%
6%
9
9
47.4%
47.4%
1
5.2%
365
38
129
198
75 (56-90)
10.4%
35.3%
54.3%
19
2
8
9
65 (57-85)
10.5%
42.1%
47.4%
The 6th National Scientific Conference on HIV/AIDS
Results
Characteristic of study population (cont.)
Characteristic
N
Total sampled
patients
N Pts with any mutation
Median (IQR)
351
105 (47-189)
19
124 (43-179)
<100
166
47.3%
8
42.1%
≥100
185
52.7%
11
57.9%
Pre-treatment CD4 cell count (cells/µL)
Pre-treatment immunodeficiency
classification by CD4 count
351
Normal (CD4 ≥500)
7
2.0%
0
0
Mild (CD4 350-499)
18
5.0%
0
0
Advanced (200-349)
53
15.2%
4
21.1%
Severe (CD4<200)
273
77.8%
15
78.9%
The 6th National Scientific Conference on HIV/AIDS
Results
Characteristic of study population (cont.)
Characteristic
N
Total sampled
patients
N Pts with any mutation
362
421 (295-590)
19
250 (115-320)
<100
7
1.9%
3
15.8%
≥100
355
98.1%
16
84.2%
Most recent CD4 cell count (cells/µL)
Median (IQR)
Current immunodeficiency classification
by CD4 count
362
Normal (CD4 ≥500)
136
37.6%
2
10.5%
Mild (CD4 350-499)
99
27.4%
1
5.3%
Advanced (200-349)
92
25.4%
8
42.1%
Severe (CD4<200)
35
9.6%
8
42.1%
The 6th National Scientific Conference on HIV/AIDS
Results
Characteristic of study population (cont.)
Characteristic
N
Total sampled
patients
N
Pts with any
mutation
364
99.7%
19
100%
1
0.3%
0
0
NNRTI regimen
345
94.5%
19
100
PI regimen
20
5.5%
0
0
Initiating ART regimen
NNRTI regimen
PI regimen
Current ART regimen
The 6th National Scientific Conference on HIV/AIDS
Results
Prevalence of viral load suppression and HIV drug resistance
Objectives
%
95%CI
1. Prevalence of viral load suppression (VL<1000 copies/mL)
among individuals sampled who have been on ART for at least 36
months at the time of the clinic visit
95.1
92.3-96.9
a. Prevalence of viral load suppression (VL<1000 copies/mL)
among individuals sampled who have been on first-line ART for
at least 36 months
92.9
89.2-95.4
2. Prevalence of HIV drug resistance among individuals sampled
who have been on ART for at least 36 months
4.6
2.8-7.5
3. Prevalence of HIV drug resistance among individuals sampled
with viral load >1000 copies/mL
94.8
64.3-99.4
a. Prevalence of HIV drug resistance among individuals
sampled with viral load >1000 copies/mL who have been on
first-line ART for at least 36 months
93.9
59.8-99.4
The 6th National Scientific Conference on HIV/AIDS
Results
18
17
16
14
12
10
8
6
4
2
1
1
0
0
Only resistance to Only resistance to Resistance to both
NNRTI
NRTI
NNRTI and NRTI
Resistance to PI
Resistance profile among mutations
The 6th National Scientific Conference on HIV/AIDS
Results
1
0.8
0.6
0.4
0.2
0
3TC
ABC
AZT
D4T
DDI
FTC
TDF
High-level resistance
Intermediate resistance
Potential low-level resistance
Susceptible
EFV
ETR
NVP
Low-level resistance
Level of resistance among RT mutations
The 6th National Scientific Conference on HIV/AIDS
RPV
Conclusions
• This is the first survey to describe acquired HIV
drug resistance status using nationally
representative sample in Vietnam.
• The results suggest a low acquired HIV drug
resistance prevalence of 4.6% and high viral
load suppression rate of 95.1% among patients
who initiated ART for at least 36 months
The 6th National Scientific Conference on HIV/AIDS
Thank you for your attention!
• Acknowledgment
– Viet Nam Administration of HIV/AIDS Control (VAAC)
– Pasteur Institute (PI) – Ho Chi Minh city
– National Institute of Hygiene and Epidemiology
(NIHE)
– World Health Organisation (WHO)
The 6th National Scientific Conference on HIV/AIDS