20% HIV affected people in South India resistant to
ARV drugs: study

Monday, September 12, 2005 08:00 IST
Gireesh Babu, Chennai

Twenty per cent of the HIV-1 affected AntiRetroViral
(ARV) naïve individuals in South India have drug
resistance, according to a study conducted by experts
under YRG care centre for AIDS Research and Education
in Chennai.

The study conducted by a group of experts say that the
failure of ARV therapy has developed drug resistance
in HIV-1 affected patients, and the resistance will be
transmitted with the virus to other individuals. The
study shows that 20% of the HIV-1 cases have to be
treated by second line drugs, which are intended for
patients with drug resistance. The project was to
determine the prevalence of mutations at protease and
reverse transcriptase drug resistance positions in ARV
naïve individuals in Southern India.

Among the study samples of 50 HIV-1 infected
drug-naïve individuals, 10 (20%) had mutations at
known major subtype B protease drug resistance
positions and all had mutations in minor subtype B
protease drug resistance positions. In the reverse
transcriptase, 8 (16%) persons had mutations at known
subtype B drug resistance positions, 3 (6%) persons
had at Nucleoside Reverse Transcriptase Inhibitor
(NRTI) and 7 (14%) at Non Nucleoside Reverse
Transcriptase Inhibitor (NNRTI). Two persons (4%) had
mutations at NRTI and NNRTI subtype B drug resistance
positions.

Although these mutations are associated with
treatment, they are commonly encountered in naïve
patients, particularly in those infected with non-B
subtypes, according to the study. Nevertheless, the
study assures that the contemporary subtype C viruses
in Southern India are not likely exhibit high levels
of drug resistance.

The study mentions that although HIV-1 drug resistance
is usually acquired during failure of ARV therapy,
drug resistance strains are also transmitted between
individuals with the virus. In the United States and
Europe, nearly 10% of new infections are due to HIV-1
isolates harbouring resistance to at least one or the
three classes of anti-HIV drugs and the study shows
that the rate of drug resistant cases continues to
increase.

Larger scale studies are needed to better define the
genotype variation of circulating Indian subtype C
viruses and their potential impact on drug
susceptibility and clinical outcome in treated
individuals, the experts opined.

The study was conducted by Dr. Suniti Solomon, Dr. P
Balakrishnan, Dr. N Kumarasamy and Dr.S.Vidya of
Y.R.G.Care Centre for AIDS Research and Education,
Chennai, Dr.Kenneth H Mayer, Dr. Michael Newstein, Dr.
Bharat Ramaratnam of Division of Infectious Diseases,
Dept. of Medicine, Brown University Medical School,
Rhode Island, Dr. Rami Kantor and Dr. David
Katzenstein of Division of Infectious Diseases,
Stanford University, California and Dr. Sadras P
Thyagarajan, Dept. of Microbiology, University of
Madras, Chennai.

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