India has gained an incredible ground in controlling HIV since the start of the pandemic. The National AIDS Control Organization (NACO) realized early on that the western model of specialist physician management and advanced laboratory monitoring was not feasible in India. From 2004 onwards, the NACO set up antiretroviral treatment (ART) focuses, which gave one of the world's biggest free ART, and HIV testing and directing destinations all over the nation.

The present program, National AIDS Control Program IV (NACP-IV) (2012-2017) is gone for diagnosing and decreasing yearly new HIV cases by 50 percent through complete HIV treatment, instruction, care and backing for the overall public and to expand on focused mediations for the key influenced groups and those at a high danger of HIV transmission [1]. Efficacy of ART is monitored by both clinical and laboratory measures, including estimation of HIV-1 viral load and CD4 cell count, while on treatment.

WHO recommends viral load estimation as the preferred monitoring approach to diagnose and confirm treatment failure [2]. The 90-90-90 treatment targets call for 90% of those living with HIV to know their status, 90% of those who know their status to be on treatment, and 90% of those on treatment to be virally suppressed [3]. However, in low and middle-income countries, such monitoring has proved difficult given the inadequate laboratory facilities, shortage of trained staff and expensive reagents. The success of ART depends on the maintenance of long-term virological suppression, which is particularly challenging.

Plasma HIV-1 RNA (viral load) testing quantifies theHIV viral burden in the plasma. The viral load is a standard tool used to monitor treatment response in patients taking ART and, in conjunction with the CD4+ T cell count, to assess HIV progression. In some situations, viral load may factor into decisions to initiate or change ART [4]. A study have shown that patients who have high plasma viral loads have an increased risk of progression to symptomatic disease and AIDS compared with patients who have low or undetectable levels [5]. Based on the recommendations of Consolidated Treatment Guidelines of World Health Organization (WHO) and National Consolidated guideline on HIV prevention, treatment, and care.

Compared toclinical or immunological monitoring, viral load provides an early and more accurate indicationof treatment failure and the need to switch from first-line to second-line drugs, reducing the accumulation of drug resistance mutations and improving clinical outcomes. Measuring viral loadcan also help to distinguish between treatment failure and non-adherence. Studies suggest thataround 70 % of patients on first-line ART, who have a first high viral load, will be suppressed following an adherence intervention, indicating non-adherence as the reason for the initial highviral load in the majority of cases [6].

Each patient was followed-up every month for clinical assessment (body weight, WHO stage, opportunistic infections) and adverse drug reaction (ADR) till completion of 1 year of second line treatment. CD4 count was monitored at baseline, 6 and 12 months while plasma viral load (PVL) was tested at baseline and 6 months after switching to second line ART regimen. Patients were offered adherence counseling at each visit. Adherence to second line ARDs was assessed by pill count. The data was recorded in Microsoft Excel Worksheet and analyzed with Excel software programs.

Study population and baseline characteristics: A total of 147 patients aged >18 years initiated second-line therapy between January 2009 to January 2010.

Baseline characteristics: A total of 147 HIV infected patients received second line ART of which 114 were men and 33 were women. All the 147 patients were treated with regimen TL, ATV/r. The mean age of patients was 38.3±8.2 years. Of 147 patients, 142 had at least one HIV positive family member; of which 5 patients were serodiscordant. The most common cause to switch on second line ART was combined immunological and clinical failure (135) followed by all three failure (12).Duration of first line ART therapy below 5 years – 106, and above 5 years was 41.

Mean baseline CD4 count was 220.06 (95% confidence interval [CI]: 243.73-196.38) and mean base line ofPVL of patients was 291356.6 cells/mm³ (95% CI: 364843.8-217869.29) copies/ml, respectively. Baseline characteristics, mean CD4 count and mean PVL of patients receiving regimen TL, ATV/r were comparable.

with viral suppression (<400 copies/ml) at 12 months. 25 patients were expired till now. It was found that poor personal habits (tobacco, smoking, and alcohol), WHO stage III/IV condition, low baseline CD4 count and high baseline PVL were associated with poor treatment outcome in terms of failure to achieve virological suppression [Table 2].

Safety assessment and adherence- A total of 25 adverse drug reactions (ADRs) were observed in during the studyperiod. The most common ADR was diarrhoea, anemia, dyslipidemia, nephro toxicity.

The pill count showed that the majority of patients (94%, 95% CI: 89-97) on second line ART were adherent to the treatment with more than 95% compliance. The number of tablets to be consumed by each patient per day in regimen TL, ATV/ris 2per day respectively.

This study reports the outcome of patients receiving secondline antiretroviral therapy under the National AIDScontrolprogram of India. To our knowledge, this is the first study to systematically evaluate the Virological outcomes of second-line ART in patients who fail first-line therapy in Telangana and Andhra Pradesh.

As the extent of ART in developing countries continues, and the number of patients switching to second line therapy will inevitably increase. Our study shows an analysis describing the outcomes of 147 patients on second line TL, ATV/rbased ART regimens for 12 months treated at Centre of Excellence (COE), Gandhi Hospital Secundrabad, Telangana, India. After 12 months of follow-up on second line regimens, Of 147 patients 116 showed TND (Target not detected) and 6 patients were showing with viral suppression (<400 copies/ml) at 12 months. 25 patients were expired till now.

The pill count showed that the majority of patients (94%, 95% CI: 89-97) on second line ART were adherent to the treatment with more than 95% compliance. In another study [7]interestingly, 17/50 (34.0 %) of patients who had ongoing viremia or virological failure at 6 months adequately suppressed their viral load at 12 months. Another Similar findings were observed in a study where 62 % patients suspected of second-line ART failure, responded to enhanced adherence support and had a two-log decrease in their level of HIV on subsequent VL testing [8].

This early mortality can be circumvented by introducing routine virological monitoring in the program which will help in early detection of patients with failure.

Dr. Raja Rao and Dr. P. Deepak Supervised the research work and guided, Dr. Krishna analyzed data and wrote the paper. P. Malikarjun performed bioinformatics analyses.

Authors would like to thank the Telangana State AIDS Control Society (TSACS) for granting permission and financial support tocarry out the work. The authors would also like to thank SACEP coordinator P.N. Sailaja and all the patients who participated in this study.

Competing Interests: The authors declare that they have no competing interests.

Abbreviations

ART: antiretroviral therapy

TL: Tenofovir + lamivudine

LPV/r: lopinavir/ritonavir

NACO: National AIDS control organization;

PLHIV: people living with HIV

VL-viral load