In primary infection

Wide variations in the prevalence of drug-resistant HIV in newly infected and treatment-naive individuals have been reported, together with differences in the rates of change in prevalence over time.

Across Europe, several large recent studies have reported that around 10% to 14% of new infections are drug-resistant.

  • The CATCH study assessed resistance in over 1630 newly infected people in Europe between 1996 and 2002, finding primary resistance mutations in 10% of the group: NRTI resistance mutations in 7%, NNRTI mutations in 3%, and PI mutations in 2%.1
  • An analysis of 2208 newly infected Europeans, first presented in 2003, found drug resistance in 11%.2 Similar rates were found in the SPREAD study of 1,083 newly infected individuals from 17 European countries, with only 1% of the study group demonstrating dual-class resistance.3
  • In the French Primo study of 303 patients with acute HIV infection, 14% had resistance mutations: 10% to NRTIs, 3% to NNRTIs, and 4% to PIs.4
  • In the French Odyssee cohort of 363 newly infected, treatment-naive patients, 6% had resistance mutations: 4% to NRTIs, 1% to NNRTIs and 1% to PIs.4
  • In the Swiss HIV cohort study of 858 recently infected participants, 8% had resistance mutations: 2% to NRTIs, 6% to NNRTIs, and 3% to PIs.5

Other, smaller or more geographically limited studies have reported comparable findings.6,7,8 9 10 Reports in certain areas and time periods have been considerably higher.11 12 

In the United Kingdom, rates have varied with time, reaching a high around 2002 and then declining. From 1994 to 2000, 14% of newly infected individuals (seroconverters) had resistant virus, but 27% of people who contracted HIV in 2000 were infected with drug-resistant virus.13 In 2002, 27% of gay men identified as recent seroconverters in England, Wales, and Northern Ireland had resistance to at least one drug, compared to 20% in 2001.14

The UK Drug Resistance Database shows that the prevalence of genotypic resistance in antiretroviral-naive individuals in the United Kingdom has declined from 16% in 2002 to 12% in 2003 and 8% by the end of 2004. Most of the resistant cases were resistant to a single drug class (4.5% to NRTIs or NNRTIs, 2.1% to PIs); 17% to two drug classes, and 8% to three. Resistance in antiretroviral-experienced individuals is also showing a downward trend.15 16

Estimates of drug-resistant new infections in the United States also vary, from reports of 8% to 9% prevalence in treatment-naive people 17 18 19 to nearly 25% in others.20 21 Upward trends in overall resistance have been shown in many cities (3% between 1995 and 1998 versus 12% between 1999 and 2000).20 22 However, at least in San Francisco and New York, the prevalence of NRTI resistance has been declining: by 2001, to 6% in San Francisco and 3% in New York. 22 21

In the Swiss HIV Cohort Study, researchers found an 8% overall prevalence of transmitted drug resistance (6% NNRTI, 3% PI, and 2% NRTI class) during the period 1996-2005. Analysis of data from 858 participants found no temporal increase in the prevalence of transmitted drug resistance, with the exception of a rise in transmission of NNRTI-resistant strains from 0% in 2004 to 6% in 2005. An average of 3.4 drugs were affected by transmitted resistance. A 2% prevalence of dual- or triple-class resistance did not reflect a significant increase. Of gender, exposure category, ethnicity, and subtype, only infection with subtype B was a factor in the prevalence of transmitted drug resistance; however, this too was not a temporal change. The researchers found that effective ART by itself can help contain the spread of primary HIV drug resistance; in particular, through the use of boosted PI-based regimens for first-line treatment regimens.5

In Montreal, Canada, a decline in resistance amongst newly infected individuals has been noted since 2000, and this is significantly correlated with the proportion of patients receiving antiretroviral treatment, a drop in the average viral load of chronically infected people and the availability of resistance testing.23

A study carried out between June 2000 and March 2002 found no significant increase in transmitted drug resistance when compared with the periods 1995 to 1998 and 1998 to 2000. Indeed, NRTI and PI resistance in seroconverters declined significantly when 2000 to 2002 was compared with 1998 to 2000, with much of the resistance detected in the 2000 to 2002 period attributable to NNRTI resistance. Multidrug resistance declined significantly, from 7 to 1%.

References

  1. van der Vijver DAMC et al. Analysis of more than 1600 newly diagnosed patients with HIV from 17 European countries shows that 10% of the patients carry primary drug resistance: The CATCH study. Second International AIDS Society Conference, Paris, late breaker 1, 2003
  2. Wensing AMJ et al. Prevalence of drug-resistant HIV-1 variants in untreated individuals in Europe: implications for clinical management. J Infect Dis 192: 958-966, 2005
  3. Wensing AMJ et al. First representative prospective surveillance data on HIV baseline drug resistance from 17 countries in Europe; the SPREAD-programme. Fourth European HIV Drug Resistance Workshop, Monte Carlo, abstract 1, 2006
  4. Descamps D et al. French national sentinel survey of antiretroviral drug resistance in patients with HIV-1 primary infection and in antiretroviral-naïve chronically infected patients in 2001-2002. J Acquir Immune Defic Syndr 38: 545-552, 2005
  5. Yerly S et al. Transmission of HIV-1 drug resistance in Switzerland: a 10-year molecular epidemiology survey. AIDS 21(16): 2223-2229, 2007
  6. Brenner B et al. Resistance to antiretroviral drugs in patients with primary HIV-1 infection. Investigators of the Quebec Primary Infection Study. Int J Antimicrob Agents 16: 429-434, 2000
  7. Wegner S et al. Prevalence of genotypic and phenotypic resistance to anti-retroviral drugs in a cohort of therapy-naive HIV-1 infected US military personnel. AIDS 14: 1009-1015, 2000
  8. Verbiest W et al. Prevalence of HIV-1 drug resistance in antiretroviral-naive patients: a prospective study. AIDS 15: 647-650, 2001
  9. Bielawski KP et al. Occurrence of HIV-1 drug-resistant mutations in Poland among patients selected for HAART. First European HIV Resistance Workshop, Luxembourg, abstract 66, 2003
  10. Kucherer C et al. Transmission of drug-resistant HIV: an update of the German seroconverter study. First European HIV Resistance Workshop, Luxembourg, abstract 55, 2003
  11. Loveday C et al. High prevalence of multiple drug resistance mutations in a UK HIV/AIDS patient population. AIDS 13: 627-628, 1999
  12. Tamalet C et al. Resistance of HIV-1 to multiple antiretroviral drugs in France: a 6-year survey (1997 2002) based on an analysis of over 7000 genotypes. AIDS 17: 2383 - 2387, 2003
  13. UK Collaborative Group on Monitoring the Transmission of HIV Drug Resistance. Analysis of prevalence of HIV-1 drug resistance in primary infections in the United Kingdom. Br Med J 322: 1087-1088, 2001
  14. Rinck G et al. Trends in transmitted antiretroviral drug resistance in men who have sex with men attending genitourinary medicine clinics in England, Wales and Northern Ireland. Fifteenth International AIDS Conference, Bangkok, abstract PpC4713, 2004
  15. Health Protection Agency, Centre for Infections The UK Collaborative Group for HIV and STI Surveillance. A Complex Picture. HIV and other Sexually Transmitted Infections in the United Kingdom Health Protection Agency, 2006
  16. UK Collaborative HIV Cohort (CHIC) Study Steering Committee. Rate of AIDS diseases or death in HIV-infected antiretroviral therapy-naive individuals with high CD4 cell count. AIDS 21: 1717-1721, 2007
  17. Becker M et al. HIV-1 genotypic resistance in treatment-naive subjects enrolled in an observational trial (GAIN). Antivir Ther 7: S134, 2002
  18. Ross L et al. Prevalence of antiretroviral drug resistance and resistance mutations in antiretroviral therapy (ART)-naive HIV-infected individuals from 40 US cities during 2003. 44th Interscience Conference on Antimicrobial Agents and Chemotherapy, Washington, abstract H-173, 2004
  19. Weinstock H et al. The epidemiology of antiretroviral drug resistance among drug-naive HIV-1-infected persons in 10 US cities. J Infect Dis 189: 2174-2181, 2004
  20. Little S et al. Antiretroviral-drug resistance among patients recently infected with HIV. N Engl J Med 347: 385-394, 2002
  21. Simon V et al. Evolving patterns of HIV-1 resistance to antiretroviral agents in newly infected individuals. AIDS 16: 1511-1519, 2002
  22. Grant RM et al. Time trends in primary HIV-1 drug resistance among recently infected persons. JAMA 188: 181-188, 2002
  23. Routy JP et al. Link between the declines of drug-resistance prevalence in newly infected individuals and of the proportion of patients receiving treatment in Montreal. Antivir Ther 7: S147, 2002
Community Consensus Statement on Access to HIV Treatment and its Use for Prevention

Together, we can make it happen

We can end HIV soon if people have equal access to HIV drugs as treatment and as PrEP, and have free choice over whether to take them.

Launched today, the Community Consensus Statement is a basic set of principles aimed at making sure that happens.

The Community Consensus Statement is a joint initiative of AVAC, EATG, MSMGF, GNP+, HIV i-Base, the International HIV/AIDS Alliance, ITPC and NAM/aidsmap
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