Case Discussion: HIV resistance and salvage regimens The 3 rd HIV-NAT Symposium Series Wasana Prasitsuebsai, MD, MPH 25 th July 2013

Case 1 A 6 year-old Thai boy presented at HIV-NAT clinic with poor weight gain and chronic cough and dyspnea. Perinatally HIV infection with lymphocytic interstitial pneumonitis were identified (CDC B). d4T/3TC/NVP were initiated and switched to AZT/3TC/NVP when he was 8 year-old. His father and mother died since he was young. He lives with grandparents and aunts in the slum. His home is a gambling house.

Progression Age (years) BW (kg) CD4% (CD4 count; cells/mm 3 ) HIV-RNA (copies/mL) HAARTRemark 6121 (22)132,000d4T/3TC/NVPStart treatment (451)<50AZT/3TC/NVPTo prevent LD (472)<40AZT/3TC/NVP (GPO-vir Z) (439)149GPO-vir ZPill count 66% 14 y 6 m (411)2719GPO-vir ZPill count 83%

VOTE now Question What is next step? 1.Continue GPO-vir Z with adherence counselling and HIV status disclosure 2. Switch to once daily regimen (EFV-based HAART) 3. Genotypic resistance testing then switch to second-line HAART 4. Switch to second-line HAART without genotypic resistance testing

Answer discussion 1. Continue GPO-vir Z with adherence counselling with disclosure Incorrect. HIV disclosure should be considered. Adherence counselling should be performed continually. But a failing regimen should not be continued. 2. Switch to once daily regimen (EFV-based HAART) Incorrect 3. Genotypic resistance testing then switch to second-line HAART Correct 4. Switch to second-line HAART without genotypic resistance testing Incorrect. Genotyping can be performed under the National Program. Genotyping should be performed before switching to the next regimen.

Progression Genotypic resistance testing was performed at last visit. His resistance testing identified: – M184V – V108I – Y181C Which ARV will be affected by these mutations?

NNRTI Mutations

Question What should be the best second-line regimen? 1. TDF + AZT + LPV/r 2. TDF + 3TC + LPVr once daily regimen 3. AZT + 3TC + LPV/r 4. TDF + 3TC + ATV/r VOTE now

Answer Discussion 1. TDF + AZT + LPV/r Optional. Patient has to take ARVs twice daily. 2. TDF + 3TC + LPV/r once daily regimen Best option as this is once daily regimen. It may help to improve adherence to ART. 3. AZT + 3TC + LPV/r Optional. Patient has to take ARVs twice daily. 4. TDF + 3TC + ATV/r ATV/r is not co-formulated and harder to take. Not a good option for this child since he had poor adherence.

d4T or AZT + 3TC + NVP or EFV Select 2NRTI according to genotyping*/ARV history + 1 Protease inhibitor LPV/r (preferred) ATV/r (alternative) Select 2NRTI according to genotyping*/ARV history + 1 Protease inhibitor LPV/r (preferred) ATV/r (alternative) Treatment Failure 2010 Thai MOPH Guidelines *Send genotyping when VL > 2000 copies/ml Recommended Second-line Regiments in Children with Treatment Failure of First-line Regimens

Clinical Progression Age (years) BW (kg) CD4% (CD4 count; cells/mm 3 ) HIV-RNA (copies/mL) HAARTRemark 6121 (22)132,000d4T/3TC/NVPStart treatment (451)<50AZT/3TC/NVPTo prevent LD (472)<40AZT/3TC/NVP (GPO-vir Z) (439)149GPO-vir ZPill count 66% 14 y 6 m (411)2719GPO-vir ZPill count 83% TC/TDF/LPV/r OD 15 y 3 m (497)<203TC/TDF/LPV/r ODPill count 92% 16 y (344)65,8703TC/TDF/LPV/r ODPill count 90%

Question What is your management plan? 1. Follow-up and continue TDF/3TC/LPV/r with adherence counselling and repeat VL next 3 months 2. Switch to a third-line regimen 3. Stop ART 4. Therapeutic drug monitoring (TDM) 5. Genotypic resistance testing VOTE now

Answer Discussion 1. Follow-up with adherence counselling and repeat VL Correct 2. Switch to a third-line regimen Incorrect 3. Stop ART Incorrect 4. Therapeutic drug monitoring (TDM) Optional if accessible. TDM can help identify poor adherence. 5. Genotypic resistance testing Incorrect. It should be performed in case of persistent detectable VL after adherence strengthening.

Progression Adherence problem was discussed with patient and his grandfather. Social worker team helped call patient to remind his ARV schedule randomly TDF/3TC/LPV/r regimen was continued. VL was repeated every 6 months Genotypic resistance testing was performed with TDM at next visit. Results revealed: – LPV Cmin level – undetectable – RTV Cmin level – undetectable – Resistance: no NRTI, NNRTI and PI mutations identified

Progression Adherence problem was discussed with patient and his grandfather. Social worker team helped call patient to remind his ARV schedule randomly. TDF/3TC/LPV/r regimen was continued. VL was repeated every 6 months. Genotypic resistance testing was performed with TDM at next visit. Results revealed: – LPV Cmin level – undetectable – RTV Cmin level – undetectable – Resistance: no NRTI, NNRTI and PI mutations identified What should we do next?

Case 2 A 15 years 6 months boy with perinatally HIV infection Refer to HIV-NAT after failing the 2 nd line regimen BW 38 kg, height 159 cm CDC A, No active HIV-related illness AgeART Start-Stop DateReason to Stop 2AZT monotherapy Switched to HAART 8d4T/3TC/NVP Unknown 9d4T/3TC/EFV Virologic failure 10d4T/3TC/NFV Virologic failure 11IDV/LPV/r IDV toxicity 153TC/LPV/r2011-going on

CD4, VL and Genotypic Resistant Mutations The patient were receiving 3TC plus LPV/r DateAge (yr)ARTCD4% (cells/mm3)HIV RNA (copies/ml) Feb IDV/LPV/r30 (963)<40 Jan TC/LPV/r26 (596)52,200 Mar TC/LPV/r18 (284)86,800 Mutations NRTIM41L, D67N, T69D, K70R, M184V, K219Q NNRTIA98G, K101H, Y181C, G190A PIL10F, K20R, L33I, M36I, M46L, I54V, T74S, N83D, I84V

Genotypic Mutations What is your third-line HAART for this patient? 1. ddI/3TC/darunavir/r 2. TDF/3TC/darunavir/r 3. TDF/3TC/etravirine/darunavir/r 4. TDF/3TC/darunavir/r/raltegravir Mutations NRTIM41L, D67N, T69D, K70R, M184V, K219Q NNRTIA98G, K101H, Y181C, G190A PIL10F, K20R, L33I, M36I, M46L, I54V, T74S, N83D, I84V

69 insertion complex + TAMs at 41, 210 or complex (Q151M+others, TDF not resistant) Multi-NRTI resistance (≥ 4 thymidine analog mutations) 69 insertion complex + TAMs at 41, 210 or complex (Q151M+others, TDF not resistant) Multi-NRTI resistance (≥ 4 thymidine analog mutations) Johnson VA, Topics in Antiviral medicine, March 2013 Multi-NRTI Mutations

NRTI Mutations K65R = tenofovir resistance (mainly selected by TDF, d4T) AZT prevents K65R when used with TDF M184V = 3TC, FTC resistance (delays TAMs) TAMs = M41L, D67N, K70R, L210W, T215Y/F, K219Q/E K65R = tenofovir resistance (mainly selected by TDF, d4T) AZT prevents K65R when used with TDF M184V = 3TC, FTC resistance (delays TAMs) TAMs = M41L, D67N, K70R, L210W, T215Y/F, K219Q/E

NNRTI Mutations Resistance to NVP and EFV = require 1 major mutation Universal cross resistance between NVP and EFV Resistance to etravirine = require > 1 major mutation K103N = no resistance to etravirine Resistance to NVP and EFV = require 1 major mutation Universal cross resistance between NVP and EFV Resistance to etravirine = require > 1 major mutation K103N = no resistance to etravirine

PI Mutations Multiple mutations required for reduced activity ATV/r and LPV/r have different patterns of resistance DRV = negative impact by I47V (LPV), I84V (ATV) but positive impact by V82A (LPV) Multiple mutations required for reduced activity ATV/r and LPV/r have different patterns of resistance DRV = negative impact by I47V (LPV), I84V (ATV) but positive impact by V82A (LPV)

Answer Discussion 1.ddI/3TC/darunavir/r Incorrect 2. TDF/3TC/darunavir/r Correct 3. TDF/3TC/etravirine/darunavir/r Incorrect. ETR score is TDF/3TC/darunavir/r/raltegravir The best option

Progression DateARTCD4% (cells/mm3) HIV RNA (copies/ml) Remark Mar 20113TC/LPV/r18 (284)86,800 Jan 20123TC/LPV/r16 (288)104,201Refer to HIV-NAT Feb 2012TDF/3TC/DRV/r May 2012TDF/3TC/DRV/r17 (302)24705Pill count 99% Aug 2012TDF/3TC/DRV/r19 (314)45849Pill count 99% What is your management? 1. Continue TDF/3TC/DRV/r with VL monitoring and adherence counseling 2. Perform genotypic resistance testing 3. Add AZT and RAL 4. Add ETR, RAL and AZT

PI Mutations MajorV32I, M46L, I54L, I84V MinorL10F, L33I, N83D OthersI13V, L19LV, A22V, E35D, M36I, R41K, I62IV, I64V, H69K, K70KR, G73DG, T74S, I85IV, L89I, T91s

Progression DateART CD4% (cells/mm3) HIV RNA (copies/ml) Remark Mar 20113TC/LPV/r18 (284)86,800 Jan 20123TC/LPV/r16 (288)104,201 Refer to HIV-NAT Feb 2012TDF/3TC/DRV/r May 2012TDF/3TC/DRV/r17 (302)24705Pill count 99% Aug 2012TDF/3TC/DRV/r19 (314)45849Pill count 99% Jan 2013AZT/TDF/3TC/RAL/DRV/r Apr 2013AZT/TDF/3TC/RAL/DRV/r20 (308)<20

Take Home Message Children have fewer ARV options than adults especially for treatment of first- and second-line treatment failure. TDF may be used in children with multi NRTI failure who do not have K65R and have wt>30 kg or Tanner >4. Use of new drugs should be done with expert advice. Viral load monitoring after switching to a new regimen is recommended to detect early failure.

Back Up Case

Case 3 A 12 year-old HIV-infected girl CDC clinical classification B (TB lung) Underlying Homozygous HbE disease Live with parents, good adherence to ARVs, disclosed by mom Hb 9.4%, CD4 34% (1085), VL 3370 copies/mL Age (years)ART 2ddI / AZT 4d4T / 3TC / NVP 9AZT / 3TC / NVP 123TC

Genotypic Mutations Mutations NRTIM41L, D67N, L210W, T215Y, K219E, M184V NNRTIK103N What is your second-line HAART for this patient? 1. TDF + AZT + LPV/r 2. TDF + 3TC + LPVr 3. ABC + ddI + LPV/r 4. ABC + 3TC + LPV/r

69 insertion complex + TAMs at 41, 210 or complex (Q151M+others, TDF not resistant) Multi-NRTI resistance (≥ 4 thymidine analog mutations) 69 insertion complex + TAMs at 41, 210 or complex (Q151M+others, TDF not resistant) Multi-NRTI resistance (≥ 4 thymidine analog mutations) Johnson VA, Topics in Antiviral medicine, March 2013 Multi-NRTI Mutations

NRTI Mutations K65R = tenofovir resistance (mainly selected by TDF, d4T) AZT prevents K65R when used with TDF M184V = 3TC, FTC resistance (delays TAMs) TAMs = M41L, D67N, K70R, L210W, T215Y/F, K219Q/E K65R = tenofovir resistance (mainly selected by TDF, d4T) AZT prevents K65R when used with TDF M184V = 3TC, FTC resistance (delays TAMs) TAMs = M41L, D67N, K70R, L210W, T215Y/F, K219Q/E

NNRTI Mutations Resistance to NVP and EFV = require 1 major mutation Universal cross resistance between NVP and EFV Resistance to etravirine = require > 1 major mutation K103N = no resistance to etravirine Resistance to NVP and EFV = require 1 major mutation Universal cross resistance between NVP and EFV Resistance to etravirine = require > 1 major mutation K103N = no resistance to etravirine

Answer Discussion 1.TDF + AZT + LPV/r Incorrect. Patient had anemia. 2. TDF + 3TC + LPVr Correct 3. ABC + ddI + LPV/r Optional (ABC is not available through the National Program) 4. ABC + 3TC + LPV/r Optional

Progression ART was switched to TDF/3TC/LPV/r BID regimen Month of 2 nd line HAART BW (kg) CD4% (CD4 count; cells/mm 3 ) HIV-RNA (copies/mL) (971) (1298)<40