Juan Gonzalez Perez AIDS Healthcare Foundation Is AZT-3TC-NVP still the best choice? Clinical outcomes of antiretroviral therapy in a Ugandan cohort Juan Gonzalez Perez AIDS Healthcare Foundation
Background Studies have found that TDF-containing regimens associated with less drug substitution and better tolerance compared with AZT regimens. Results on mortality and retention are conflicting, with some observational studies suggesting that AZT-3TC-NVP could be associated with better outcomes (Chi 2011, Eguzo 2014)
Objectives Estimate 12 months attrition by regimen in a cohort of patients initiated on ART in 4 sites in Uganda Compare clinical outcomes in the first year on ART between the four first line regimens recommended by WHO
Methods Retrospective observational cohort study. Exposure= ARV regimen during the 1st year of treatment. Outcome: 12 months attrition (LTFU+ death) Site: 4 facilities supported by AHF in Uganda: 2 Kampala/ 2 Central Region. Duration of the study: August 2005 until November 2014
Methods Study population: Adults (15 and above) started on AZT or TDF- containing 1st line regimens with complete demographic, baseline and follow up clinical data including: Age, gender, Baseline weight, WHO stage and CD4, ART start date, regimens and history TB treat 1st year ART
Statistical analysis Descriptive analysis: Patient characteristics at ART initiation by regimen compared using chi-squared or Kruskal-Wallis testing. Analytical techniques used: Kaplan-Meier survival methods to determine time to attrition Cox proportional hazards model to adjust for potential confounders Robust SE Propensity scores to account for non-randomized regimen allocation
Study Sites (Uganda)
Results
Cohort description 11,795 adults starting TDF or AZT containing regimens 7,017 excluded because: 6,365 missing baseline data 652 incomplete information on ART regimens first year 5,430 meet eligibility criteria for analysis cohort 1,061 (20%) start AZT-3TC-NVP 3,066 (56%) Start TDF-3TC-EFV 980 (18%) Start TDF-3TC-NVP 323 (6%) Start AZT-3TC-EFV
Population description Total (n=5,430) AGE: median (IQR) 32 (27-39) SEX Male: % 41% WEIGHT: median (IQR) 56 (50-63) WHO STAGE 3-4: % 22% CD4: median (IQR) 273 (143-382) YEAR of initiation 2011 or before 2012-2013 2014 415 (8%) 3112 (57%) 1903 (35%) TB treatment 1st year ART 293 (5%) Health facility: Site 1 Site 2 Site 3 Site 4 2,051 (38%) 916 (17%) 1570 (29%) 893 (16%) Outcomes LTFU Death Total attrition 851 133 984 (18%)
Population description AZT/3TC/NVP (n=1,061) TDF/3TC/EFV (n=3,066) TDF/3TC/NVP (n=980) AZT/3TC/EFV (n=323) p-value AGE: median (IQR) 33 (29-41) 31 (26-38) 33 (28-41) 35 (28-41) <0.001 SEX Male: % 47% 38% 46% 45% WEIGHT: median (IQR) 56 (50-62) 57 (50-64) 55 (49-62) 57(51-64) WHO STAGE 3-4: % 27% 19% 25% 29% CD4: median (IQR) 197 (110-281) 327 (195-436) 198 (113-295) 312 (177-414) YEAR of initiation 2011 or before 2012-2013 2014 246 (23%) 680 (64%) 135 (13%) 39 (1%) 1483 (48%) 1545 (51%) 84 (9%) 750 (77%) 146 (15%) 47 (15%) 199 (61%) 77 (24%) TB treatment 1st year ART 23 (2%) 191 (7%) 18 (2%) 51 (16%) Health facility: Site 1 Site 2 Site 3 Site 4 245 (23%) 106 (10%) 515 (49%) 195 (18%) 1,123 (37%) 653 (21%) 725 (24%) 565 (18%) 603 (61%) 107 (11%) 189 (19%) 81 (8%) 80 (25%) 50 (15%) 141 (44%) 52 (16%) Outcomes LTFU Death Total attrition 157 27 184 (17%) 483 57 540 (18%) 161 41 202 (20%) 50 8 58 (17%) 0.003
Population description AZT/3TC/NVP (n=1,061) TDF/3TC/EFV (n=3,066) TDF/3TC/NVP (n=980) AZT/3TC/EFV (n=323) p-value AGE: median (IQR) 33 (29-41) 31 (26-38) 33 (28-41) 35 (28-41) <0.001 SEX Male: % 47% 38% 46% 45% WEIGHT: median (IQR) 56 (50-62) 57 (50-64) 55 (49-62) 57(51-64) WHO STAGE 3-4: % 27% 19% 25% 29% CD4: median (IQR) 197 (110-281) 327 (195-436) 198 (113-295) 312 (177-414) YEAR of initiation 2011 or before 2012-2013 2014 246 (23%) 680 (64%) 135 (13%) 39 (1%) 1483 (48%) 1545 (51%) 84 (9%) 750 (77%) 146 (15%) 47 (15%) 199 (61%) 77 (24%) TB treatment 1st year ART 23 (2%) 191 (7%) 18 (2%) 51 (16%) Health facility: Site 1 Site 2 Site 3 Site 4 245 (23%) 106 (10%) 515 (49%) 195 (18%) 1,123 (37%) 653 (21%) 725 (24%) 565 (18%) 603 (61%) 107 (11%) 189 (19%) 81 (8%) 80 (25%) 50 (15%) 141 (44%) 52 (16%) Outcomes LTFU Death Total attrition 157 27 184 (17%) 483 57 540 (18%) 161 41 202 (20%) 50 8 58 (17%) 0.003
Kaplan-Meier analysis 12 months Attrition AZT/3TC/NVP 18% AZT/3TC/EFV 19% TDF/3TC/EFV 21% TDF/3TC/NVP 22% Log rank p-value= 0.09
Multivariable analysis: Cox model aHR (95% CI) p-value ART regimen AZT/3TC/NVP Ref TDF/3TC/EFV 1.48 (1.23-1.69) <0.001 TDF/3TC/NVP 1.26 (1.03-1.54) 0.02 AZT/3TC/EFV 1.22 (0.91-1.65) 0.17 Sex (male) 1.19 (1.03-1.37) 0.01 Age (10 year increase) 0.90 (0.83-0.97) WHO Stage 3-4 1.29 (1.10-1.52) 0.002 Weight 0.97 (0.96-0.98) < 0.001 CD4 baseline cells/uL < 100 100-200 0.64 (0.53-0.8) > 200 0.57 (0.43-0.74) Year ART initiation 2011 or before 2012-2013 1.37 (1.90-2.10) 0.13 2014 0.87 (0.45-1.67) 0.68 TB treatment 1st year 0.91 (0.68-1.22) 0.65
Conclusion In the data from our cohort AZT-3TC-NVP was associated with better retention at 12 months when compared with TDF-containing regimens Inferiority of TDF+3TC+NVP has been suggested in comparative studies before. For TDF+3TC+EFV, we hypothesized that in contexts like the one in our study, with limited access to investigations and reduced capacity to rule out OI, the increased potency of TDF+3TC+EFV to suppress viral replication (and cause more severe IRIS in those with undetected OIs) could be one factor to explain its negative performance
Acknowledgements Buzaalirwa Lydia Ssamula Kate Ikapule Jonathan Ssali John Lubanga Augustine Ssemakadde Matthew Babakhani Arin Iutung Amor Penninah Agnes Kiragga
Thank you
Observational studies comparing 1st line regimens SSA Bygrave 2011: 1124 patients started in TDF, d4T or AZT regimens in 2008 in Lesotho No difference between groups in terms of mortality and LTFU Chi 2011: 18,866 patients starting ARV in Lusaka 2007-2010, looking at the association between ARV regimen (initial, at time of event, predominant exposure) and outcomes Results of AZT-3TC-NVP were better than TDF regimens when categorizing drug regimen at time of event on Mortality and Program failure (30d lag time)
Observational studies comparing 1st line regimens SSA Velen 2014: 6169 patients started in TDF, d4T or AZT regimens between 2007 and 2009 from 2 different programs (workplace and community) in SA Sensitivity analysis in the community program didn’t find differences in mortality and LTFU between TDF and AZT regimens Eguzo 2014: 1069 patients started 2008-2013 in Nigeria In Cox model mortality of patients started on TDF regimens was higher (HR 1.88, p=0.03) compared with patients initiated on AZT/3TC regimens