Dr Andrew Ustianowski

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1 15 TH ANNUAL CONFERENCE OF THE BRITISH HIV ASSOCIATION ( BHIVA) Dr Andrew Ustianowski North Manchester General Hospital 1-3 April 2009, Arena and Convention Centre Liverpool Top 10 Papers of Andy Ustianowski Monsall Infectious Diseases Unit North Manchester General Hospital 2

2 What is not included... ARV comparative studies Some have been very important Artemis, Castle etc. Data known, discussed & digested long before publication of paper Other well known studies DAD, SMART etc. Again fully discussed and digested long before formal publication What I have included... Questions that come up in clinic... Can I be cured via bone marrow transplant? How long will I live? I hear its OK to have unsafe sex... History When did HIV arise in humans? Prevention Vaccines, PrEP What does HIV interact with in the cell? Low-abundance drug-resistant viral variants A new way of assessing ARV activities How are we doing globally? 3

3 Questions that come up in clinic... Can I be cured via bone marrow transplant? How long will I live? I hear its OK to have unsafe sex... 4

4 Hutter et al. NEJM 2008 Background: 32-bp deletions occur naturally in CCR5 allele resulting in an inactive CCR5 gene product delta32/delta32 homozygosity in 1% Caucasians confers high resistance against HIV-1 acquisition Hutter et al. NEJM 2009;360:692-8 Case Report 40yr newly diagnosed acute myeloid leukaemia HIV+ >10yrs HAART for 4yrs (TDF, FTC, EFV) No AIDS defining illnesses CD4=415 VL=undetectable Induction & consolidation chemotherapy 7/12 later AML relapse allogenic stem-cell transplant Hutter et al. NEJM 2009;360:

5 Received stem-cell transplant from donor screened as being delta32/delta32 Conditioning regimen, rabbit anti-thymocyte globulin, cyclosporin, mycophenolate HAART discontinued on day of procedure Day 332 AML relapse Re-induction, cytarabine, gemtuzumab Second transplant from same donor & whole body irradiation Remission at month 20 Hutter et al. NEJM 2009;360:692-8 What about the HIV is it cured? No HAART since transplant HIV RNA & pro-viral DNA undetectable Blood, bone marrow or rectal mucosa HIV-antigenic stimulus apparently gone HIV-specific T-cells undetectable Some loss of HIV-antibody responses Hutter et al. NEJM 2009;360:

6 Further points Routine genotypic tests pre-transplant demonstrated R5 only virus However ultra-deep sequencing demonstrated small proportion of X4 Rectal biopsy at day 159 CCR5 expressing macrophages still present but no HIV DNA detected Hutter et al. NEJM 2009;360:

7 Antiretroviral Therapy Cohort Collaboration Multinational cohort study of naive patients commencing cart Canada, Europe & USA 14 cohorts 43,355 eligible patients 2050 deaths (4.7%) ARV Therapy Cohort Collaboration. Lancet 2008;372:293-9 Life Expectancy ARV Therapy Cohort Collaboration. Lancet 2008;372:

8 Subgroups ARV Therapy Cohort Collaboration. Lancet 2008;372:

9 Background Consensus statement from Swiss Federal Commission for HIV/AIDS 1 : Those with undetectable plasma HIV viraemia (VL<40 copies/ml), and without other genital infections, cannot transmit HIV through sexual contact Evidence: Rakai cohort 2 Strong relation between plasma HIV VL & heterosexual transmission rates 0 transmission from 51 partners with UD VL Spanish cohort 3 No infections between heterosexual partners with UD VL 1 Vernazza et al. Bulletin des Medecins Suisses 2008;89:165-9 ; 2 Quinn et al. NEJM 2000;342:921-9 ; 3 Castilla et al. J AIDS 2005;40: Wilson et al. Lancet 2008;372: Methods Mathematical modelling Using results of Rakai study of heterosexual transmission 1 each 10-fold increment in VL associated with a 2.45-fold (95% CI ) increase in risk of HIV transmission per sexual contact Assumptions: This incremental increase Applies to female-male, male-female & male-male sex Applies across the range of VL, including below detectable Probability of receptive penile-vaginal , insertive penilevaginal 0.001, penile-anal 0.01 (transmission per sex act) Untreated HIV has VL between 10 4 and 10 5 used VL Quinn et al. NEJM 2000;342: Wilson et al. Lancet 2008;372:

10 Cumulative risk of HIV transmission with varying VL Insertive penile-vaginal Receptive penile-vaginal Penile-anal Wilson et al. Lancet 2008;372: Condoms? If condom use is maintained at 80% (and deemed to be 95% effective per act) then over 10 years expect transmissions in 10,000 couples to be: 52 for female-male 104 for male-female 990 for male-male Therefore if condoms not used (as per original model) Incidence increased 4 times Wilson et al. Lancet 2008;372:

11 History When did HIV arise in humans? 12

12 Worobey et al. Nature 2008 Background: Oldest known HIV infection was from 1959 (none others sampled prior to 1976) Now a further sequence from a paraffin-embedded lymph node biopsy described Leopoldville, Belgian Congo (now Kinshasa, DRC) Allows comparative evolutionary genetic study of early HIV-1 viruses (i.e. estimate date of most recent common ancestor of ZR59 & DRC60) Worobeyet al. Nature 2008;455(2):661-4 Validity Legitimate isolation of HIV Multiple independent PCR reactions Different laboratories etc. Very low rate (1.4%) variance between laboratories implies little damage-induced mutations Comparisons with known more recent HIV sequences and known evolution Blinded estimate of age of DRC60 = 1959 Worobeyet al. Nature 2008;455(2):

13 When did these viral strains diverge? (rooted tree topology) Time to most recent common ancestor (TMRCA) = 1908 ( ) Worobeyet al. Nature 2008;455(2):661-4 How does this fit in with urbanisation? Bayesian Skyline Plot - tracks effective population size through time HIV-1 experienced an extensive period of relatively slow growth in the first half of 20 th Century Rise of cities may have facilitated the initial establishment and early spread of HIV Founding & growth of colonial administration and trading centres such as Kinshasa may have enabled the region to become the epicentre of the HIV pandemic Worobeyet al. Nature 2008;455(2):

14 Prevention Vaccines, PrEP 15

15 Background Cell-mediated vaccines a potential way forward Adenovirus type 5 (Ad5) vector-based vaccines very immunogenic SIV Ad5 worked to control viraemia in some primate models Candidate vaccine of Ad5 & HIV-1 gag, pol and nef genes developed Phase 1 good immunogenicity whether Ad5 sero-positive or negative Buchbinder et al. Lancet 2008;371: Test-of of-concept Trial Multicentre, doubleblind, randomised, placebo-controlled of MRKAd5 vaccine In HIV-negatives at high risk of HIV N & S America, Caribbean, Australia 1ml day 1, week 4 & week 26 Stratification to Ad5 antibody titres <18, , and >1000 Endpoints: Reduction in HIV acquisition rates Decrease in viral load set-point if sero-convert Buchbinder et al. Lancet 2008;371:

16 Numbers Buchbinder et al. Lancet 2008;371: HIV Seroconversions by Ad5 titres Rates higher in vaccine recipients if Ad5>18 Buchbinder et al. Lancet 2008;371:

17 No effect on viral load set-points p>0.25 for all comparisons Buchbinder et al. Lancet 2008;371: Increased risk especially in Ad5 seropositive and uncircumcised Buchbinder et al. Lancet 2008;371:

18 HIV incidence roughly constant over time Buchbinder et al. Lancet 2008;371: Conclusions Vaccine did not prevent HIV or reduce early viral load Increased HIV infection rates in vaccine recipients with prior Ad5 antibodies and uncircumcised Why? A confounder? Assessing HSV rates & sexual networks Mucosal immune activation? Mucosal immunity being investigated Something else? Buchbinder et al. Lancet 2008;371:

19 Change in directions of HIV vaccine research... Anthony Fauci. HIV Vaccine Research: The Way Forward. Science 2008;321: Dan Barouch. Challenges in the development of an HIV-1 vaccine. Nature 2008;455: Also disappointments in vaginal microbicides Skoler-Karpoff et al. Efficacy of Carraguard for the prevention of HIV infection in women in S Africa. Lancet 2008;371: Grant et al. Whither or Wither Microbicides? Science 2008;321:

20 Pre-exposure exposure prophylaxis (PrEP ( PrEP) PrEP proven concept for malaria and other infections Mathematical models estimate an effective PrEP could prevent million new HIV-1 infections in SS Africa over next 10 years Garcia-Lermaet al. PLOS Medicine 2008;5:291-9 Methods Repeat-low-dose exposure model in macaques SHIV virus challenge contains an R5 tropic HIV-1 envelope Chimeric virus with tat, rev & env of HIV-1 Low/physiological mucosal inoculum 7.6x10 5 RNA copies Akin to semen levels in acute HIV Multiple potential transmission events Rectal exposure weekly for 14 weeks 1ml, non-traumatic, recumbent for 15mins Garcia-Lermaet al. PLOS Medicine 2008;5:

21 Study Design FTC subcutaneously Tenofovir & FTC orally Tenofovir & FTC subcutaneously Tenofovir & FTC subcutaneously Intermittent 2hr pre & 24hr post Daily Oral drug doses established as achieving plasma and intracellular concentrations similar to seen in humans Subcutaneous doses exceed usual human concentrations & may be toxic Garcia-Lermaet al. PLOS Medicine 2008;5:291-9 Protection Weekly PCR & serology performed Considered protected if seronegative and negative for plasma RNA & PBMC DNA during PrEP and after 70 days washout (in absence of drugs) All breakthrough infections (n=6) with wild-type virus but under continuing drug therapy 4 developed resistance mutations Garcia-Lermaet al. PLOS Medicine 2008;5:

22 Conclusions Moderate protection for Truvada-equivalent oral daily PrEP Complete protection from high-dose subcut. FTC/Tenofovir either: daily or intermittent (2hr pre- and 24hr post-challenge) Garcia-Lermaet al. PLOS Medicine 2008;5:291-9 What does HIV interact with in the cell? 23

23 Methods : Genome-wide RNA interference screen to identify host factors involved in HIV infection Small interfering RNA (sirna) transfected cells infected with HIV-1 48hr later stained for p24 (viral entry) Culture supernatants placed with fresh cells 24hr later assayed for Tat-dependent reporter gene expression (Late acting factors) Genome-wide sirnas Brass et al. Science 2008;319:

24 Host proteins required for HIV infection identified Brass et al. Science 2008;319:921-6 Host proteins required for HIV-1 infection Brass et al. Science 2008;319:

25 Low-abundance drug-resistant viral variants 26

26 Background Current clinical genotypic resistance tests are restricted to mutations that >20% prevalence Ultradeep sequencing may detect ~1% prevalence Some data suggests that these minority variants may influence outcome on ARV for naive patients 1 1 Shafer. JID 2009;199: Simenet al. JID 2009;199: Methods FIRST study (USA naive study) NRTI & NNRTI NRTI & PI (unboosted) NRTI & NNRTI & PI (unboosted) Conventional drug resistance analysis = 10.8% prevalence 454 parallel sequencing technique utilised on subset of 258 patients Baselines minority resistance correlated with outcome Simenet al. JID 2009;199:

27 Prevalence of drug-resistance resistance mutations Simenet al. JID 2009;199: Resistance & outcome NNRTI & NRTI Regimen: 11/11 with NNRTI resistance identified at baseline failed Hazard ratios for Resistance > 20% = 5.99 (95% CI ) Resistance < 20% = 2.41 (95% CI ) PI & NRTI Regimen Simenet al. JID 2009;199:

28 Conclusions Minor (low-abundance) drug resistant HIV variants common in naive HIV-1 Do they lead to failure? Time to VF for whole cohort not different whether ultradeep resistance detected or not However if randomised to a ARV strategy that corresponded to the mutations detected an associated was seen with NNRTI resistance. Similar findings found in other studies using different methodology 1 PI resistance only in 5 patients placed on PI regimen and probably under-powered to detect similar 1 Shafer. JID 2009;199: Simenet al. JID 2009;199: A new way of assessing ARV activities 29

29 Shen et al. Nat Med 2008 Rationale: Clinical outcome of ART may depend on whether 99% or 99.99% inhibition of HIV is achieved IC50 and Inhibitory Quotient (IQ) are too insensitive for this... Method: Analysis of dose-response curves for ART in single-round infectivity assay with the sensitivity to detect infection of a single cell Shen et al. Nat Med 2008;14(7):

30 IC50 and IIP IIP = Instantaneous Inhibitory Potential the log reduction in infectivity at clinically relevant concentrations Shen et al. Nat Med 2008;14(7):762-6 What does this mean for 2 differing drugs AZT & EFV? Shen et al. Nat Med 2008;14(7):

31 What about all the drugs? Shen et al. Nat Med 2008;14(7):762-6 IIP is not the sole answer decay in IIP with missed doses... Shen et al. Nat Med 2008;14(7):

32 Does this fit in with studies? Shen et al. Nat Med 2008;14(7):762-6 What does it all mean? Authors conclusions: IIP provides a more accurate in-vitro pharmacodynamic measure of antiviral activity than traditional measures But many other factors in the magnitude & durability of viral load suppression Pharmacokinetics, distribution, toxicity, adherence, interactions, barriers to resistance Intriguing potential insights into drug efficacy if true Shen et al. Nat Med 2008;14(7):

33 How are we doing globally? Report on the global HIV/AIDS epidemic

34 Report on the global HIV/AIDS epidemic Decrease in new infections in children Report on the global HIV/AIDS epidemic

35 ARV roll-out out Report on the global HIV/AIDS epidemic Number of people living with HIV and HIV prevalence Report on the global HIV/AIDS epidemic

36 15 th Annual Conference of the British HIV Association (BHIVA) 1-3 April 2009, Arena and Convention Centre Liverpool 1-3 April 2009, Arena and Convention Centre Liverpool 37