Outcomes after virologic failure of first-line ART in South Africa (original) (raw)

Rates and predictors of failure of first-line antiretroviral therapy and switch to second-line ART in South Africa

2012

Objectives-To measure rates and predictors of virologic failure and switch to second-line ART in South Africa. Design-Observational cohort study Methods-We included ART-naïve adult patients initiated on public-sector ART (Jan 2000-July 2008) at five sites in South Africa who completed ≥6 months of follow-up. We estimated cumulative risk of virologic failure (viral load ≥400 copies/ml with confirmation above varying thresholds) and switching to second-line ART. Results-19,645 patients (29,935 person-years) had a median of 1.3 years of study follow-up (1.8 years on ART) and a median CD4 count of 96 (IQR:40-159) cells/μl at ART initiation. 9.9% (4.5/100 person-years) failed ART in median 16 (IQR:12-23) months since ART initiation, with median 2.9 (IQR:1.8-5.0) months between first elevated and confirmatory viral loads. By survival analysis, using a confirmatory threshold of 400 copies/ml, 16.9% (95%CI:15.4-18.6%) failed by

Virological Failure and Drug Resistance in Patients on Antiretroviral Therapy After Treatment Interruption in Lilongwe, Malawi

Clinical Infectious Diseases, 2012

Background. Since 2004, Malawi has rapidly scaled up access to antiretroviral therapy (ART) in the national program following a public health approach with limited laboratory monitoring. We examined virological outcomes in patients with treatment interruption at 2 clinics of the Lighthouse Trust, Lilongwe, Malawi. Methods. We evaluated patients who resumed first-line ART after having at least 1 treatment interruption documented in the electronic data system in 2008-2009. Viral load (VL) was analyzed at least 2 months after resumption of ART. For VL ≥1000 copies/mL, drug-resistance genotype was characterized using the Stanford database. Results. Between June and November 2009, we enrolled 133 patients (58.7% female) with a mean age of 38.4 years. Mean duration of ART prior to treatment interruption was 14.3 months. After a minimum of 2 months following ART resumption, VL was undetectable in 81 (60.9%) patients, was 400-1000 copies/mL in 12 (9.0%) patients, and was ≥1000 copies/mL in 40 (30.1%) patients. Genotyping and drug-resistance testing were successfully performed for 36 of 40 patients, all carrying human immunodeficiency virus type 1 subtype C. Relevant mutations affecting nonnucleoside reverse transcriptase inhibitors were found in 32 of 133 (24.1%) patients and combined with relevant nucleoside reverse transcriptase mutations in 27 of 133 (20.3%) patients. Conclusions. Virological failure combined with drug resistance after resumption of first-line ART occurred in 24.1% of the patients with treatment interruption, requiring a switch to protease inhibitor-based second-line therapy. Patients with treatment interruption should receive VL assessment after resumption of ART to detect treatment failure and to reduce development and spread of drug resistance.

Drug level testing as a strategy to determine eligibility for drug resistance testing after failure of ART: a retrospective analysis of South African adult patients on second‐line ART

Journal of the International AIDS Society

Introduction: When protease inhibitor (PI)-based second-line ART fails, guidelines recommend drug resistance testing and individualized third-line treatment. However, PI-resistant viral strains are rare and drug resistance testing is costly. We investigated whether less costly PI-exposure testing can be used to select those patients who would benefit most from drug resistance testing. Methods: We performed a retrospective analysis of South African adults living with HIV experiencing failure of ritonavirboosted-lopinavir (LPV/r)-based second-line ART for whom drug resistance testing results were available. We included patients who received plasma-based drug resistance testing at a central South African reference laboratory in 2017 and patients who received dried blood spots (DBS)-based drug resistance testing at a rural South African clinic between 2009 and 2017. PI-exposure testing was performed on remnant plasma or DBS using liquid chromatography mass spectrometry (LCMS). Additionally, a low-cost immunoassay was used on plasma. Population genotypic drug resistance testing of the pol region was performed on plasma and DBS using standard clinical protocols. Results: Samples from 544 patients (494 plasma samples and 50 DBS) were included. Median age was 41.0 years (IQR: 33.3 to 48.5) and 58.6% were women. Median HIV-RNA load was 4.9 log10 copies/mL (4.3 to 5.4). Prevalence of resistance to the NRTI-backbone was 70.6% (349/494) in plasma samples and 56.0% (28/50) in DBS. Major PI-resistance mutations conferring high-level resistance to LPV/r were observed in 26.7% (132/494) of plasma samples and 12% (6/50) of DBS. PI-exposure testing revealed undetectable LPV levels in 47.0% (232/494) of plasma samples and in 60.0% (30/50) of DBS. In pooled analysis of plasma and DBS samples, detectable LPV levels had a sensitivity of 90% (84% to 94%) and a negative predictive failure of 95% (91% to 97%) for the presence of major LPV/r resistance. Conclusions: PI-exposure testing revealed non-adherence in half of patients experiencing failure on second-line ART and accurately predicted the presence or absence of clinically relevant PI resistance. PI-exposure testing constitutes a novel screening strategy in patients with virological failure of ART that can differentiate between different underlying causes of therapy failure and may allow for more effective use of limited resources available for drug resistance testing.

Lopinavir/ritonavir monotherapy after virologic failure of first-line antiretroviral therapy in resource-limited settings

AIDS, 2012

Objective: To evaluate virologic response rates of lopinavir/ritonavir (LPV/r) monotherapy as second-line antiretroviral treatment (ART) among adults in resource-limited settings (RLSs). Design: An open-label pilot study of LPV/r monotherapy in participants on first-line nonnucleoside reverse transcriptase inhibitor three-drug combination ART with plasma HIV-1 RNA 1000-200 000 copies/ml. Methods: Participants were recruited from five sites in Africa and Asia within the AIDS Clinical Trials Group (ACTG) network. All participants received LPV/r 400/100 mg twice daily. The primary endpoint was remaining on LPV/r monotherapy without virologic failure at week 24. Participants with virologic failure were offered addition of emtricitabine and tenofovir (FTC/TDF) to LPV/r. Results: Mutations associated with drug resistance were encountered in nearly all individuals screened for the study. One hundred and twenty-three participants were enrolled, and 122 completed 24 weeks on study. A high proportion remained on LPV/r monotherapy without virologic failure at 24 weeks (87%). Archived samples with HIV-1 RNA levels less than 400 copies/ml at week 24 (n ¼ 102) underwent ultrasensitive assay. Of these individuals, 62 had levels less than 40 copies/ml and 30 had levels 40-200 copies/ml. Fifteen individuals experienced virologic failure, among whom 11 had resistance assessed and two had emergent protease inhibitor mutations. Thirteen individuals with virologic failure added FTC/TDF and one individual added FTC/ TDF without virologic failure. At study week 48, 11 of 14 adding FTC/TDF had HIV-1 RNA levels less than 400 copies/ml. Conclusion: In this pilot study conducted in diverse RLS, LPV/r monotherapy as second-line ART demonstrated promising activity.

Third-Line Antiretroviral Therapy Program in the South African Public Sector: Cohort Description and Virological Outcomes

Journal of Acquired Immune Deficiency Syndromes, 2019

Background: The World Health Organization recommends that antiretroviral therapy (ART) programs in resource-limited settings develop third-line ART policies. South Africa developed a national third-line ART program for patients who have failed both first-line non-nucleoside reverse transcriptase inhibitor-based ART and second-line protease inhibitor (PI)-based ART. We report on this program. Methods: Third-line ART in South Africa is accessed through a national committee that assesses eligibility and makes individual regimen recommendations. Criteria for third-line include the following: $1 year on PI-based ART with virologic failure, despite adherence optimization, and genotypic antiretroviral resistance test showing PI resistance. We describe baseline characteristics and resistance patterns of this cohort and present longitudinal data on virological suppression rates. Results: Between August 2013 and July 2014, 144 patients were approved for third-line ART. Median age was 41 years [interquartile range (IQR): 19-47]; 60% were women (N = 85). Median CD4 + count and viral load were 172 (IQR: 128-351) and 14,759 (IQR: 314-90,378), respectively. About 2.8% started PI-based ART before 2004; 11.1% from 2004 to 2007; 31.3% from 2008 to 2011; and 6.3% from 2012 to 2014 (48.6% unknown start date). Of the 144 patients, 97% and 98% had resistance to lopinavir and atazanavir, respectively; 57% had resistance to darunavir. All were initiated on a regimen containing darunavir, with raltegravir in 101, and etravirine in 33. Among those with at least 1 viral load at least 6 months after third-line approval (n = 118), a large proportion (83%, n = 98) suppressed to ,1000 copies per milliliter, and 79% (n = 93) to ,400 copies per milliliter. Conclusion: A high proportion of third-line patients with followup viral loads are virologically suppressed.

Magnitude and correlates of virological failure among adult HIV patients receiving PI based second line ART regimens in north western Tanzania; a case control study

Background: With a growing access to free ART, switching of ART to second line regimen has also become common following failure of first line ART regimens. Patients failing on first line ART regimens have been shown to stand a high risk of failing on subsequent second line ART regimens. The magnitude of those who are failing virologicaly on second line ART is not documented in our setting. This study was designed to assess the magnitude and correlates of second line ART treatment failure. Methods: A retrospective analysis of patients on second line ART for at least 1 year was done at Bugando care and treatment center. Information on demographic, clinical and laboratory data were collected and analyzed using STATA 11. The proportion of patients with Virological failure was calculated and potential correlates of virological failure were determined by logistic regression model. Results: In total 197 patients on second line ART were included in this study and 24 (12.18%) of them met criteria for virological failure. The odds of having virological failure on second line ART were independently associated with age of less than 30 years (AOR = 12.5, p = 0.001), being on first line for less than 3 years (AOR = 6.1, p = 0.002) and CD4 at switch to second line ART of less than 200cells/μl (AOR = 16.3, p < 0.001). Conclusion: Virological failure among patients on second line ART is common. Predictors of virological failure in this study could assist in planning for strategies to improve the outcome of this subgroup of patients including close clinical follow up of patients at risk, a continued adherence intensification and a targeted resistance testing before switching to second line ART.