Articles tagged as "Portugal"

How do we know which activities make a difference to HIV prevention?

Editor’s notes: In order to be fairly certain that an intervention is responsible for changes in HIV or HIV-related behaviours, the gold standard is randomization. This allows for fair comparisons between groups, since factors that might alter the outcomes will be more or less equally balanced between the study groups.  This is true whether such confounding factors are expected, but also importantly, even those factors that are unknown, unexpected and unmeasured will also be balanced between the arms. 

A second key determinant of high quality research is to use an approach that maximizes full engagement and follow-up of participants in the study.  One such approach that is widely recognized is to use Good Participatory Practice.  

Rhodes and colleagues study condom promotion and HIV testing among the Hispanic/Latino community of gay men and other men who have sex with men in North Carolina, USA.  Although gay men and other men who have sex with men represent approximately 4% of the adult male population in the United States of America, they account for more than 80% of new HIV infections among men.  Around one quarter of gay men and other men who have sex with men are Hispanic or Latino.  The authors therefore wanted to use research to make a difference to the HIV burden of the Hispanic/Latino gay men and other men who have sex with men community in North Carolina, USA.  They found that despite the impact of HIV on Hispanic/ Latino gay men and other men who have sex with men, they were only able to identify one evidence-based behavioural HIV prevention programme focussed on this population.

The authors used an extensive community based participatory research partnership, whose members represented the Hispanic/ Latino gay men and other men who have sex with men community, AIDS service organizations, Hispanic/Latino-serving community organizations, and universities to develop, implement, and evaluate a Spanish-language, small group intervention designed to increase condom use and HIV testing among Hispanic/Latino gay men and other men who have sex with men (HOLA en Grupos).

304 participants were randomly allocated to the HOLA en Grupos intervention, or to a general health education comparison intervention having the same number of sessions (4) and duration (16 hours in total) that focussed on prostate, lung, and colorectal cancers; diabetes; high cholesterol; cardiovascular disease; and alcohol misuse. These topics for the control group were identified on the basis of identified needs and priorities of Hispanic/Latino gay men and other men who have sex with men.

HOLA en Grupos is grounded on social cognitive theory, empowerment education, and traditional Hispanic/Latino cultural values and includes four interactive modules of four hours each delivered in groups.  Participants in both intervention and control arms received reimbursement for their time, certificates of completion and meals and a celebration at the completion of the course.  In other words this was an intensive intervention that might be hard to replicate in most settings, but it follows very high standards both for developing and conducting the research and also for determining the impact of the intervention.

The intervention was associated with a large effect on both condom usage (four-fold higher in the intervention arm than the control) and HIV test uptake (an astonishing 14-fold higher, reflecting the relatively low testing rate in the control group).

A major limitation in many HIV prevention studies, including this one, is that the outcome is based on reported behaviour.  The challenge is that the real outcome of interest, which is new HIV infections, is relatively rare in almost all communities so that studies have to be huge and expensive, and the large majority of participants in both intervention and control arms do not in fact acquire HIV.  This is in contrast to most studies of treatment, where there are clearly defined biological, standardized measures which many or all participants are likely to reach.  Nonetheless, there are many examples of studies that find changes in reported behaviour that are not associated with biological markers of such change (such as incidence of HIV or other sexually transmitted infections, or pregnancy). 

There are also many observational or ecological studies that report changes in new HIV infections but that cannot truly say why the number of infections fell and whether the interventions used in the study were responsible for the changes.  For example Nwokolo and colleagues report in a short research letter on the dramatic decline in new HIV diagnoses in the large London clinic where they work.  New infections in that clinic, and in fact in other large clinics in London, have dropped by a remarkable 40% from 2015 to 2016, as originally reported in the popular science press before any scientific publication or presentation. The authors of the research letter are suitably cautious about how to account for the impressive decline.  Various systems have been improved over the past few years in this clinic to make it easier to have an HIV test and start treatment immediately.  However, most of the clinic team (and many other commentators) assume that it is also due to the rapid rise in the use of PrEP.  Although it is still not available through the UK National Health Service, the clinic has been at the forefront of encouraging gay men and other men who have sex with men who might benefit from PrEP to purchase it from on-line pharmacies.  The clinic then provides the appropriate monitoring and follow up to ensure that their clients get the best possible PrEP service given the current constraints.  Whatever the cause, we should be celebrating the rapid fall in new HIV infections across London, which is home to a substantial proportion of the new HIV infections in the UK.

The challenges of demonstrating evidence of effectiveness for HIV prevention is also felt among black women in the USA.  Although they have the highest burden of HIV among women in the USA, the incidence rates are such that a traditional randomized trial design would need to be huge, and consequently hugely expensive.  Adimora and colleagues consider whether an alternative trial design might be to use data from high HIV incidence settings and then to develop proxies of protection, such as the concentration of a PrEP medicine to infer whether black women are protected.  An alternative that has been proposed for men who have sex with men would be to look for other markers of high risk, such as sexually transmitted infections, reported partners, age, and substance use and estimate the likely risk of HIV acquisition in the absence of PrEP from these parameters.  Then the observed incidence could be compared to this modelled counterfactual, much as was done in the open label extension of the Partners PrEP study in Kenyan and Ugandan sero-different couples.  However, translating risk factors for infection across populations, and even continents when there is such heterogeneity in risk of infection is not at all straightforward.  So there is still plenty to think about and no clear answers yet!

A useful addition to the tool box for designing studies and assessing the effectiveness of interventions, would be better tools for measuring recent infection.  There are several assays all with differing characteristics but increasingly these differences and how they interact with different clades of HIV are becoming clear.  Key determinants for each assay are the mean duration of recent infection (MDRI) estimate (which does seem to vary by clade) and the false recency rate (FRR) which needs to be less than 2% to be considered useful.  Hargrove and colleagues used three different assays to test samples from 101 women who seroconverted during the ZVITAMBO trial.  The MDRI measured using standard cut-off points, were considerably shorter than those published for the general population.  The authors point out that changes in antibody properties among women who have recently given birth or other unspecified physiological states, mean that incidence assays may give different results from those published and expected.  Yet more caution when comparing incidence estimates between studies.  As an endpoint in a comparison between two groups in the same population, the assays are still attractive. Although, given typical MDRIs of around six to nine months, these assays will still need to be embedded in very large samples to give reliable estimates of incidence and statistically significant differences between groups.

This month saw the production of a useful supplement on many aspects of how data from different sources, including incidence assays are used to inform the sophisticated models on which so much HIV planning, programming and financing is based.  An example is Mahiane and colleagues’ paper on the development of a new tool to fit existing programme data into the spectrum suite of models in order to estimate incidence.

Finally in this section, for those who are keen on laboratory studies, Richardson-Harman and colleagues describe the current state of ex-vivo challenge models for assessing potential candidates as microbicides.  In these models, biopsies of rectal, cervical or vaginal tissue, taken during other procedures, or from volunteers, are kept alive in the laboratory.  The tissues can then be challenged with HIV in the presence or absence of potential microbicide products.  The current model works best for rectal tissues, in which infection occurs promptly and consistently, so that the effect of a microbicide can clearly be seen by a reduction in the production of HIV p24 antigen.  However, for cervical and vaginal tissues, the infection (in the absence of any microbicide) was less consistent, slower and lasted longer making it less easy to determine statistical differences between those tissues with microbicide and those without.  Further work of this sort may help to streamline the choice of microbicide or PrEP products that can most sensibly be taken out of the laboratory and into the (almost) real world of clinical trials.

Small-group randomized controlled trial to increase condom use and HIV testing among Hispanic/Latino gay, bisexual, and other men who have sex with men.

Rhodes SD, Alonzo J, Mann L, Song EY, Tanner AE, Arellano JE, Rodriguez-Celedon R, Garcia M, Freeman A, Reboussin BA, Painter TM. Am J Public Health. 2017 Jun;107(6):969-976. doi: 10.2105/AJPH.2017.303814. Epub 2017 Apr 20.

Objectives: To evaluate the HOLA en Grupos intervention, a Spanish-language small-group behavioral HIV prevention intervention designed to increase condom use and HIV testing among Hispanic/Latino gay, bisexual, and other men who have sex with men.

Methods: In 2012 to 2015, we recruited and randomized 304 Hispanic/Latino men who have sex with men, aged 18 to 55 years in North Carolina, to the 4-session HOLA en Grupos intervention or an attention-equivalent general health education comparison intervention. Participants completed structured assessments at baseline and 6-month follow-up. Follow-up retention was 100%.

Results: At follow-up, relative to comparison participants, HOLA en Grupos participants reported increased consistent condom use during the past 3 months (adjusted odds ratio [AOR] = 4.1; 95% confidence interval [CI] = 2.2, 7.9; P < .001) and HIV testing during the past 6 months (AOR = 13.8; 95% CI = 7.6, 25.3; P < .001). HOLA en Grupos participants also reported increased knowledge of HIV (P < .001) and sexually transmitted infections (P < .001); condom use skills (P < .001), self-efficacy (P < .001), expectancies (P < .001), and intentions (P < .001); sexual communication skills (P < .01); and decreased fatalism (P < .001).

Conclusions: The HOLA en Grupos intervention is efficacious for reducing HIV risk behaviors among Hispanic/Latino men who have sex with men.

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Not just PrEP: other reasons for London's HIV decline.

Nwokolo N, Whitlock G, McOwan A. Lancet HIV. 2017 Apr;4(4):e153. doi: 10.1016/S2352-3018(17)30044-9.

The reduction in HIV diagnoses in London in 2016 is attributed to pre-exposure prophylaxis (PrEP). We believe that the causes of the 42% decline seen at our clinic are likely to be multifactorial. 56 Dean Street diagnoses one in four of London's HIV cases, 50% of whom have incident infection (ie, within 4 months of infection). Because of this, and following the results of the START study, we actively recommend treatment at, or close to, diagnosis, reducing the risk of transmission in people who would otherwise be highly infectious.

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US black women and HIV prevention: time for new approaches to clinical trials.

Adimora AA, Cole SR, Eron JJ Clin Infect Dis. 2017 Apr 5. doi: 10.1093/cid/cix313. [Epub ahead of print]. 

Black women bear the highest burden of HIV infection among US women. Tenofovir/ emtricitabine HIV prevention trials among women in Africa have yielded varying results. Ideally, a randomized controlled trial (RCT) among US women would provide data for guidelines for US women's HIV pre-exposure prophylaxis use. However, even among US black women at high risk for HIV infection, sample size requirements for an RCT with HIV incidence as its outcome are prohibitively high. We propose to circumvent this large sample size requirement by evaluating relationships between HIV incidence and drug concentrations measured among participants in traditional phase 3 trials in high incidence settings - and then applying these observations to drug concentrations measured among at risk individuals in lower incidence settings, such as US black women. This strategy could strengthen the evidence base to enable black women to fully benefit from prevention research advances and decrease racial disparities in HIV rates.

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Heightened HIV antibody responses in postpartum women as exemplified by recent infection assays: implications for incidence estimates.

Hargrove JW, van Schalkwyk C, Humphrey JH, Mutasa K, Ntozini R, Owen SM, Masciotra S, Parekh BS, Duong YT, Dobbs T, Kilmarx PH, Gonese E. AIDS Res Hum Retroviruses. 2017 May 24. doi: 10.1089/AID.2016.0319. [Epub ahead of print].

Laboratory assays that identify recent HIV infections are important for assessing impacts of interventions aimed at reducing HIV incidence. Kinetics of HIV humoral responses can vary with inherent assay properties, and between HIV subtypes, populations, and physiological states. They are important in determining mean duration of recent infection (MDRI) for antibody-based assays for detecting recent HIV infections. We determined MDRIs for multi-subtype peptide representing subtypes B, E and D (BED)-capture enzyme immunoassay, limiting antigen (LAg), and Bio-Rad Avidity Incidence (BRAI) assays for 101 seroconverting postpartum women, recruited in Harare from 1997 to 2000 during the Zimbabwe Vitamin A for Mothers and Babies trial, comparing them against published MDRIs estimated from seroconverting cases in the general population. We also compared MDRIs for women who seroconverted either during the first 9 months, or at later stages, postpartum. At cutoffs (C) of 0.8 for BED, 1.5 for LAg, and 40% for BRAI, estimated MDRIs for postpartum mothers were 192, 104, and 144 days, 33%, 32%, and 52% lower than published estimates of 287, 152 and 298 days, respectively, for clade C samples from general populations. Point estimates of MDRI values were 7%-19% shorter for women who seroconverted in the first 9 months postpartum than for those seroconverting later. MDRI values for three HIV incidence biomarkers are longer in the general population than among postpartum women, particularly those who recently gave birth, consistent with heightened immunological activation soon after birth. Our results provide a caution that MDRI may vary significantly between subjects in different physiological states.

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Improvements in Spectrum's fit to program data tool.

Mahiane SG, Marsh K, Grantham K, Crichlow S, Caceres K, Stover J.  AIDS. 2017 Apr;31 Suppl 1:S23-S30. doi: 10.1097/QAD.0000000000001359.

Objective: The Joint United Nations Program on HIV/AIDS-supported Spectrum software package (Glastonbury, Connecticut, USA) is used by most countries worldwide to monitor the HIV epidemic. In Spectrum, HIV incidence trends among adults (aged 15-49 years) are derived by either fitting to seroprevalence surveillance and survey data or generating curves consistent with program and vital registration data, such as historical trends in the number of newly diagnosed infections or people living with HIV and AIDS related deaths. This article describes development and application of the fit to program data (FPD) tool in Joint United Nations Program on HIV/AIDS' 2016 estimates round.

Methods: In the FPD tool, HIV incidence trends are described as a simple or double logistic function. Function parameters are estimated from historical program data on newly reported HIV cases, people living with HIV or AIDS-related deaths. Inputs can be adjusted for proportions undiagnosed or misclassified deaths. Maximum likelihood estimation or minimum chi-squared distance methods are used to identify the best fitting curve. Asymptotic properties of the estimators from these fits are used to estimate uncertainty.

Results: The FPD tool was used to fit incidence for 62 countries in 2016. Maximum likelihood and minimum chi-squared distance methods gave similar results. A double logistic curve adequately described observed trends in all but four countries where a simple logistic curve performed better.

Conclusion: Robust HIV-related program and vital registration data are routinely available in many middle-income and high-income countries, whereas HIV seroprevalence surveillance and survey data may be scarce. In these countries, the FPD tool offers a simpler, improved approach to estimating HIV incidence trends.

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Analytical advances in the ex vivo challenge efficacy assay.

Richardson-Harman N, Parody R, Anton P, McGowan I, Doncel G, Thurman AR, Herrera C, Kordy K, Fox J, Tanner K, Swartz G, Dezzutti CS. AIDS Res Hum Retroviruses. 2017 Apr;33(4):395-403. doi: 10.1089/AID.2016.0073. Epub 2016 Dec 16.

The ex vivo challenge assay is being increasingly used as an efficacy endpoint during early human clinical trials of HIV prevention treatments. There is no standard methodology for the ex vivo challenge assay, although the use of different data collection methods and analytical parameters may impact results and reduce the comparability of findings between trials. In this analysis, we describe the impact of data imputation methods, kit type, testing schedule and tissue type on variability, statistical power, and ex vivo HIV growth kinetics. Data were p24 antigen (pg/ml) measurements collected from clinical trials of candidate microbicides where rectal (n = 502), cervical (n = 88), and vaginal (n = 110) tissues were challenged with HIV-1BaL ex vivo. Imputation of missing data using a nonlinear mixed effect model was found to provide an improved fit compared to imputation using half the limit of detection. The rectal virus growth period was found to be earlier and of a relatively shorter duration than the growth period for cervical and vaginal tissue types. On average, only four rectal tissue challenge assays in each treatment and control group would be needed to find a one log difference in p24 to be significant (alpha = 0.05), but a larger sample size was predicted to be needed for either cervical (n = 21) or vaginal (n = 10) tissue comparisons. Overall, the results indicated that improvements could be made in the design and analysis of the ex vivo challenge assay to provide a more standardized and powerful assay to compare efficacy of microbicide products.

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Stigma and sex work

Editor’s notes: Two interesting studies this month looked at aspects of stigma.  There are big methodological challenges to the study of stigma.  Stigma comprises several different domains and few studies use standardized approaches to measurement that can be translated easily into other contexts.  A systematic review and meta-analysis concludes that people who feel more stigmatized are twice as likely to delay presenting for HIV care.  Gesesew HA and colleagues found only ten studies that met their pre-specified inclusion criteria, and five of these came from Ethiopia.  They acknowledge many of the challenges in combining the results of these ten studies into a single conclusion.  They recommend engagement of health care workers to try to reduce perceived stigma among people living with HIV.

The Nyblade L et al. study from Kenya emphasizes the perception of stigma among sex workers.  In a large sample of 497 females and 232 males, most reported experiencing stigma both verbal and measured from health care workers. For female sex workers, the anticipation of such stigma led to avoidance of health services for both HIV and non-HIV related conditions. In order to provide effective services for key populations, health care workers must be trained to be non-judgemental.  HIV services need to be provided in the context of an overall package of health care.

A study from Europe used ecological data to explore structural risks for HIV among sex workers.  Reeves A and colleagues used regression modelling with data on sex work policies from 27 countries.  They showed a strong correlation between criminalisation of sex work and higher prevalence of HIV among sex workers.  Although they included other factors such as the level of economic development and using drugs, the relatively small number of data points does mean that there may be other confounding factors that could not be measured or adjusted for.

Significant association between perceived HIV related stigma and late presentation for HIV/AIDS care in low and middle-income countries: A systematic review and meta-analysis.

Gesesew HA, Tesfay Gebremedhin A, Demissie TD, Kerie MW, Sudhakar M, Mwanri L. PLoS One. 2017 Mar 30;12(3):e0173928. doi: 10.1371/journal.pone.0173928.eCollection 2017.

Background: Late presentation for human immunodeficiency virus (HIV) care is a major impediment for the success of antiretroviral therapy (ART) outcomes. The role that stigma plays as a potential barrier to timely diagnosis and treatment of HIV among people living with HIV/AIDS (acquired immunodeficiency syndrome) is ambivalent. This review aimed to assess the best available evidence regarding the association between perceived HIV related stigma and time to present for HIV/AIDS care.

Methods: Quantitative studies conducted in English language between 2002 and 2016 that evaluated the association between HIV related stigma and late presentation for HIV care were sought across four major databases. This review considered studies that included the following outcome: 'late HIV testing', 'late HIV diagnosis' and 'late presentation for HIV care after testing'. Data were extracted using a standardized Joanna Briggs Institute (JBI) data extraction tool. Meta- analysis was undertaken using Revman-5 software. I2 and chi-square test were used to assess heterogeneity. Summary statistics were expressed as pooled odds ratio with 95% confidence intervals and corresponding p-value.

Results: Ten studies from low- and middle- income countries met the search criteria, including six (6) and four (4) case control studies and cross-sectional studies respectively. The total sample size in the included studies was 3788 participants. Half (5) of the studies reported a significant association between stigma and late presentation for HIV care. The meta-analytical association showed that people who perceived high HIV related stigma had two times more probability of late presentation for HIV care than who perceived low stigma (pooled odds ratio = 2.4; 95%CI: 1.6-3.6, I2 = 79%).

Conclusions: High perceptions of HIV related stigma influenced timely presentation for HIV care. In order to avoid late HIV care presentation due the fear of stigma among patients, health professionals should play a key role in informing and counselling patients on the benefits of early HIV testing or early entry to HIV care. Additionally, linking the systems and positive case tracing after HIV testing should be strengthened.

Abstract  Full-text [free] access

The relationship between health worker stigma and uptake of HIV counseling and testing and utilization of non-HIV health services: the experience of male and female sex workers in Kenya.

Nyblade L, Reddy A, Mbote D, Kraemer J, Stockton M, Kemunto C, Krotki K, Morla J, Njuguna S, Dutta A, Barker C. AIDS Care. 2017 Mar 22:1-9. doi: 10.1080/09540121.2017.1307922. [Epub ahead of print]

The barrier HIV-stigma presents to the HIV treatment cascade is increasingly documented; however less is known about female and male sex worker engagement in and the influence of sex-work stigma on the HIV care continuum. While stigma occurs in all spheres of life, stigma within health services may be particularly detrimental to health seeking behaviors. Therefore, we present levels of sex-work stigma from healthcare workers (HCW) among male and female sex workers in Kenya, and explore the relationship between sex-work stigma and HIV counseling and testing. We also examine the relationship between sex-work stigma and utilization of non-HIV health services. A snowball sample of 497 female sex workers (FSW) and 232 male sex workers (MSW) across four sites was recruited through a modified respondent-driven sampling process. About 50% of both male and female sex workers reported anticipating verbal stigma from HCW while 72% of FSW and 54% of MSW reported experiencing at least one of seven measured forms of stigma from HCW. In general, stigma led to higher odds of reporting delay or avoidance of counseling and testing, as well as non-HIV specific services. Statistical significance of relationships varied across type of health service, type of stigma and gender. For example, anticipated stigma was not a significant predictor of delay or avoidance of health services for MSW; however, FSW who anticipated HCW stigma had significantly higher odds of avoiding (OR = 2.11) non-HIV services, compared to FSW who did not. This paper adds to the growing evidence of stigma as a roadblock in the HIV treatment cascade, as well as its undermining of the human right to health. While more attention is being paid to addressing HIV-stigma, it is equally important to address the key population stigma that often intersects with HIV-stigma.

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National sex work policy and HIV prevalence among sex workers: an ecological regression analysis of 27 European countries.

Reeves A, Steele S, Stuckler D, McKee M, Amato-Gauci A, Semenza JC. Lancet HIV. 2017 Mar;4(3):e134-e140. doi: 10.1016/S2352-3018(16)30217-X. Epub2017 Jan 25.

Background: Sex workers are disproportionately affected by HIV compared with the general population. Most studies of HIV risk among sex workers have focused on individual-level risk factors, with few studies assessing potential structural determinants of HIV risk. In this Article, we examine whether criminal laws around sex work are associated with HIV prevalence among female sex workers.

Method: We estimate cross-sectional, ecological regression models with data from 27 European countries on HIV prevalence among sex workers from the European Centre for Disease Control; sex-work legislation from the US State Department's Country Reports on Human Rights Practices and country-specific legal documents; the rule of law and gross-domestic product per capita, adjusted for purchasing power, from the World Bank; and the prevalence of injecting drug use among sex workers. Although data from two countries include male sex workers, the numbers are so small that the findings here essentially pertain to prevalence in female sex workers.

Findings: Countries that have legalised some aspects of sex work (n=17) have significantly lower HIV prevalence among sex workers than countries that criminalise all aspects of sex work (n=10; β=-2·09, 95% CI -0·80 to -3·37;p=0·003), even after controlling for the level of economic development (β=-1·86; p=0·038) and the proportion of sex workers who are injecting drug users (-1·93;p=0·026). We found that the relation between sex work policy and HIV among sex workers might be partly moderated by the effectiveness and fairness of enforcement, suggesting legalisation of some aspects of sex work could reduce HIV among sex workers to the greatest extent in countries where enforcement is fair and effective.

Interpretation: Our findings suggest that the legalisation of some aspects of sex work might help reduce HIV prevalence in this high-risk group, particularly in countries where the judiciary is effective and fair.

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Community-based HIV testing for MSM: available at an acceptable cost in Europe

Economic evaluation of HIV testing for men who have sex with men in community-based organizations - results from six European cities.

Perelman J, Rosado R, Amri O, Morel S, Rojas Castro D, Chanos S, Cigan B, Lobnik M, Fuertes R, Pichon F, Slaaen Kaye P, Agusti C, Fernandez-Lopez L, Lorente N, Casabona J. AIDS Care. 2016 Dec 27:1-5. doi: 10.1080/09540121.2016.1271392. [Epub ahead of print]

The non-decreasing incidence of HIV among men who have sex with men (MSM) has motivated the emergence of Community Based Voluntary Counselling and Testing (CBVCT) services specifically addressed to MSM. The CBVCT services are characterized by facilitated access and linkage to care, a staff largely constituted by voluntary peers, and private not-for-profit structures outside the formal health system institutions. Encouraging results have been measured about their effectiveness, but these favourable results may have been obtained at high costs, questioning the opportunity to expand the experience. We performed an economic evaluation of HIV testing for MSM at CBVCT services, and compared them across six European cities. We collected retrospective data for six CBVCT services from six cities (Copenhagen, Paris, Lyon, Athens, Lisbon, and Ljubljana), for the year 2014, on the number of HIV tests and HIV reactive tests, and on all expenditures to perform the testing activities. The total costs of CBVCTs varied from 54 390€ per year (Ljubljana) to 245 803€ per year (Athens). The cost per HIV test varied from to 41€ (Athens) to 113€ (Ljubljana). The cost per HIV reactive test varied from 1966€ (Athens) to 9065€ (Ljubljana). Our results show that the benefits of CBVCT services are obtained at an acceptable cost, in comparison with the literature (values, mostly from the USA, range from 1600$ to 16 985$ per HIV reactive test in clinical and non-clinical settings). This result was transversal to several European cities, highlighting that there is a common CBVCT model, the cost of which is comparable regardless of the epidemiological context and prices. The CBVCT services represent an effective and "worth it" experience, to be continued and expanded in future public health strategies towards HIV.

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Editor’s notes: Although HIV incidence among some key populations in Europe has declined in recent years, new cases among gay men and other men who have sex with men have steadily increased over the last decade. Among those new cases, over a third are reported late, leading to worse health outcomes for the person, as well as an increased risk of onward transmission. As a result, community-based voluntary counselling and testing has been rolled out in European cities to encouraging results in terms of effectiveness.

In that context, the authors of this paper have carried out an economic evaluation of community-based voluntary counselling and testing programmes in six cities across Europe (Athens, Copenhagen, Lisbon, Lyon, Paris and Ljubljana). They collected total annual costs of running the programmes. They found that the cost per HIV test ranged from €41 in Athens to €113 in Ljubljana and the cost per reactive HIV test ranged from €1966 to €9065 in the same two cities. The authors found that these costs are acceptable compared to those found in the literature.

Oddly, one of the more interesting results found in the article, but not discussed within the text, is the cost per reactive HIV test link to care. This varied in absolute terms (€2297- €20 215) likely due to different linkages to care rates, from 100% in Copenhagen to under 40% in Paris. Given the ultimate aims of testing (which ought to be to improve health outcomes and reduce onward transmission) this is a more important figure than the cost per test. Further research therefore should explore the unit costs further down the treatment cascade resulting from these programmes. These would be, for example, cost per person on treatment and cost per person with a suppressed viral load. 

Europe
Denmark, France, Greece, Portugal, Slovenia
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Tenofovir resistance – need for caution but not panic

Global epidemiology of drug resistance after failure of WHO recommended first-line regimens for adult HIV-1 infection: a multicentre retrospective cohort study.

TenoRes Study Group. Lancet Infect Dis. 2016 Jan 28. pii: S1473-3099(15)00536-8. doi: 10.1016/S1473-3099(15)00536-8. [Epub ahead of print]

Background: Antiretroviral therapy (ART) is crucial for controlling HIV-1 infection through wide-scale treatment as prevention and pre-exposure prophylaxis (PrEP). Potent tenofovir disoproxil fumarate-containing regimens are increasingly used to treat and prevent HIV, although few data exist for frequency and risk factors of acquired drug resistance in regions hardest hit by the HIV pandemic. We aimed to do a global assessment of drug resistance after virological failure with first-line tenofovir-containing ART.

Methods: The TenoRes collaboration comprises adult HIV treatment cohorts and clinical trials of HIV drug resistance testing in Europe, Latin and North America, sub-Saharan Africa, and Asia. We extracted and harmonised data for patients undergoing genotypic resistance testing after virological failure with a first-line regimen containing tenofovir plus a cytosine analogue (lamivudine or emtricitabine) plus a non-nucleotide reverse-transcriptase inhibitor (NNRTI; efavirenz or nevirapine). We used an individual participant-level meta-analysis and multiple logistic regression to identify covariates associated with drug resistance. Our primary outcome was tenofovir resistance, defined as presence of K65R/N or K70E/G/Q mutations in the reverse transcriptase (RT) gene.

Findings: We included 1926 patients from 36 countries with treatment failure between 1998 and 2015. Prevalence of tenofovir resistance was highest in sub-Saharan Africa (370/654 [57%]). Pre-ART CD4 cell count was the covariate most strongly associated with the development of tenofovir resistance (odds ratio [OR] 1.50, 95% CI 1.27-1.77 for CD4 cell count <100 cells per µL). Use of lamivudine versus emtricitabine increased the risk of tenofovir resistance across regions (OR 1.48, 95% CI 1.20-1.82). Of 700 individuals with tenofovir resistance, 578 (83%) had cytosine analogue resistance (M184V/I mutation), 543 (78%) had major NNRTI resistance, and 457 (65%) had both. The mean plasma viral load at virological failure was similar in individuals with and without tenofovir resistance (145 700 copies per mL [SE 12 480] versus 133 900 copies per mL [SE 16 650; p=0.626]).

Interpretation: We recorded drug resistance in a high proportion of patients after virological failure on a tenofovir-containing first-line regimen across low-income and middle-income regions. Effective surveillance for transmission of drug resistance is crucial.

Abstract  Full-text [free] access 

Editor’s notes: Global surveillance for tenofovir (TDF) resistance is important at a time of expanding use of TDF-containing regimens for treatment and prevention. This collaborative analysis used data collated from several small studies in different settings. Overall, around one in three people who had failed on TDF-containing treatment had evidence of TDF resistance, although this frequency varied between 20% in Europe to almost 60% in Africa. Mutations associated with NNRTIs and lamivudine/emtricitabine resistance were more common overall and were present in most people with TDF resistance.

The regional variation probably reflects differences in clinical practice and study inclusion criteria. All European studies involved cohorts with frequent viral load monitoring, whereas half of the African cohorts had no routine viral load monitoring. All European studies included people with virologic failure but with low-level viraemia (viral load <1000 copies/ml) whereas almost all African studies included only people with viral load >1000 copies/ml.

While these data provide useful estimates of the frequency of drug resistance mutations in people with virologic failure on first-line ART, there should be caution about extrapolating beyond this. Reports from cohort studies with an accurate denominator of all people starting TDF-containing first-line ART would be useful to give more reliable estimates of overall incidence of acquired TDF resistance. Moreover, there remains a need for representative population-based surveillance for acquired and transmitted drug resistance. So far, global surveillance has detected limited evidence of transmitted TDF-associated mutations, but this needs to be monitored closely, especially in high incidence settings.

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Abacavir: a safe first line drug for children

Adverse events associated with abacavir use in HIV-infected children and adolescents: a systematic review and meta-analysis.

Jesson J, Dahourou DL, Renaud F, Penazzato M, Leroy V. Lancet HIV. 2016 Feb;3(2):e64-75. doi: 10.1016/S2352-3018(15)00225-8. Epub 2015 Dec 7.

Background: Concerns exist about the toxicity of drugs used in the implementation of large-scale antiretroviral programmes, and documentation of antiretroviral toxicity is essential. We did a systematic review and meta-analysis of adverse events among children and adolescents receiving regimens that contain abacavir, a widely used antiretroviral drug.

Methods: We searched bibliographic databases and abstracts from relevant conferences from Jan 1, 2000, to March 1, 2015. All experimental and observational studies of HIV-infected patients aged 0-18 years who used abacavir, were eligible. Incidence of adverse outcomes in patients taking abacavir (number of new events in a period divided by population at risk at the beginning of the study) and relative risks (RR) compared with non-abacavir regimens were pooled with random effects models.

Findings: Of 337 records and 21 conference abstracts identified, nine studies (eight full-text articles and one abstract) collected information about 2546 children, of whom 1769 (69%) were on abacavir regimens. Among children and adolescents taking abacavir, hypersensitivity reactions (eight studies) had a pooled incidence of 2.2% (95% CI 0.4-5.2); treatment switching or discontinuation (seven studies) pooled incidence was 10.9% (2.1-24.3); of grade 3-4 adverse events (six studies) pooled incidence was 9.9% (2.4-20.9); and adverse events other than hypersensitivity reaction (six studies) pooled incidence was 21.5% (2.8-48.4). Between-study inconsistency was significant for all outcomes (p<0.0001 for all inconsistencies). Incidence of death (four studies) was 3.3% (95% CI 1.5-5.6). In the three randomised clinical trials with comparative data, no increased risk of hypersensitivity reaction (pooled RR 1.08; 95% CI 0.19-6.15), grade 3 or 4 events (0.79 [0.44-1.42]), or death (1.72 [0.77-3.82]) was noted for abacavir relative to non-abacavir regimens. None of the reported deaths were related to abacavir.

Interpretation: Abacavir-related toxicity occurs early after ART initiation and is manageable. Abacavir can be safely used for first-line or second-line antiretroviral regimens in children and adolescents, especially in sub-Saharan Africa where HLA B5701 genotype is rare.

Abstract access

Editor’s notes: Abacavir is a nucleoside reverse transciptase inhibitor (NRTI), available as a paediatric formulation. Abacavir in combination with lamivudine is the preferred NRTI backbone for children aged three to ten years and for adolescents weighing under 35 kilograms. It is thus part of both first- and second-line antiretroviral therapy (ART) regimens recommended for children by World Health Organization (WHO), American and European guidelines.  

In the context of implementation of large-scale ART programmes where abacavir is recommended as the NRTI of choice, understanding its toxicity is crucial. In adults the main concern is the increased risk of hypersensitivity reactions, particularly among people with the HLA B5701 genotype, and of myocardial infarction. Children have specific characteristics that affect both the pharmacokinetic profiles of drugs, and also drug tolerability in the short and the long term. Despite the widespread use of abacavir, there has been no systematic evaluation of the toxicity profile of abacavir in children. 

This systematic review of nine studies conducted between 2000 and 2015 demonstrates that there is a low risk of hypersensitivity reactions, especially for children living in sub-Saharan Africa, where 90% of children with HIV live. This is consistent with studies in adults which illustrates that the frequency of the HLAB5701 allele genotype in African populations is low, estimated to be less than two percent.

Other adverse events such as gastrointestinal symptoms and laboratory abnormalities were common. Rates of adverse events should be interpreted with caution as these could depend on factors such as other drugs in the regimen, adherence and so on. Furthermore, data on adverse events were obtained from cohort studies that were not blinded and selection or recall bias cannot be excluded.

Notwithstanding this, most adverse events occurred early after initiation of abacavir, were no more common than with other NRTI regimens, and were manageable. Importantly, there were no deaths associated with abacavir in any of the reported studies. This study supports the use of abacavir as a preferred drug in the NRTI backbone for treatment of children living with HIV. 

HIV Treatment
Africa, Europe, Latin America
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TB still responsible for large proportion of admissions and in-patient deaths among people living with HIV

TB as a cause of hospitalization and in-hospital mortality among people living with HIV worldwide: a systematic review and meta-analysis.

Ford N, Matteelli A, Shubber Z, Hermans S, Meintjes G, Grinsztejn B, Waldrop G, Kranzer K, Doherty M, Getahun H. J Int AIDS Soc. 2016 Jan 12;19(1):20714. doi: 10.7448/IAS.19.1.20714. eCollection 2016.

Introduction: Despite significant progress in improving access to antiretroviral therapy over the past decade, substantial numbers of people living with HIV (PLHIV) in all regions continue to experience severe illness and require hospitalization. We undertook a global review assessing the proportion of hospitalizations and in-hospital deaths because of tuberculosis (TB) in PLHIV.

Methods: Seven databases were searched to identify studies reporting causes of hospitalizations among PLHIV from 1 January 2007 to 31 January 2015 irrespective of age, geographical region or language. The proportion of hospitalizations and in-hospital mortality attributable to TB was estimated using random effects meta-analysis.

Results: From an initial screen of 9049 records, 66 studies were identified, providing data on 35 845 adults and 2792 children across 42 countries. Overall, 17.7% (95% CI 16.0 to 20.2%) of all adult hospitalizations were because of TB, making it the leading cause of hospitalization overall; the proportion of adult hospitalizations because of TB exceeded 10% in all regions except the European region. Of all paediatric hospitalizations, 10.8% (95% CI 7.6 to 13.9%) were because of TB. There was insufficient data among children for analysis by region. In-hospital mortality attributable to TB was 24.9% (95% CI 19.0 to 30.8%) among adults and 30.1% (95% CI 11.2 to 48.9%) among children.

Discussion: TB remains a leading cause of hospitalization and in-hospital death among adults and children living with HIV worldwide.

Abstract  Full-text [free] access

Editor’s notes: The last 30 years have seen radical improvements in outcomes for many people living with HIV. This study reminds us that in some parts of the world HIV-associated infections, tuberculosis (TB) in particular, still have a devastating effect on thousands of lives.

The importance of TB is widely recognised. WHO aim to reduce deaths due to TB by 75% over the next 10 years.  The question remains: do we really know how many people die due to TB?  Death certification has repeatedly been shown to be unreliable, particularly in the parts of the world where TB is most prevalent. Verbal autopsy is used to estimate cause of death in areas with poor notification systems, but poorly differentiates deaths due to TB and other HIV-associated conditions. Similar challenges are faced when counting and classifying morbidity and hospitalisations. Data are sparse, and determining the cause of an admission is not straightforward, even with access to well-maintained hospital records.  

This review, a sub-analysis of data from a broader study of HIV-associated hospital admissions, is by far the largest of its kind. The authors have been rigorous, given the heterogeneity of the studies included, and their findings are sobering. Among adults living with HIV, in all areas except Europe and South America, TB was the cause of 20-33% of admissions, and some 30% of adults and 45% of children who were admitted with TB were thought to have died from it. These findings are limited by the fact that not all reviewed studies reported on mortality and very few stated how causes of death were assigned.

This paper raises more questions than it answers, but they are important questions.  We are left in no doubt that TB is a major contributor to global morbidity and mortality in HIV-positive people, but we need to look closely at how we count and classify ‘TB deaths’ and ‘TB-associated admissions’. The recent systematic review of autopsy studies cited by the authors also found that almost half the TB seen at autopsy was not diagnosed before death. Global autopsy rates are in decline. Without access to more accurate data, how will we know if we’re winning or losing in our efforts to end TB deaths?

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AIDS and bacterial disease remain leading causes of hospital admission

Causes of hospital admission among people living with HIV worldwide: a systematic review and meta-analysis.

Ford N, Shubber Z, Meintjes G, Grinsztejn B, Eholie S, Mills EJ, Davies MA, Vitoria M, Penazzato M, Nsanzimana S, Frigati L, O'Brien D, Ellman T, Ajose O, Calmy A, Doherty M. Lancet HIV. 2015 Oct;2(10):e438-44. doi: 10.1016/S2352-3018(15)00137-X. Epub 2015 Aug 11.

Background: Morbidity associated with HIV infection is poorly characterised, so we aimed to investigate the contribution of different comorbidities to hospital admission and in-hospital mortality in adults and children living with HIV worldwide.

Methods: Using a broad search strategy combining terms for hospital admission and HIV infection, we searched MEDLINE via PubMed, Embase, Web of Science, LILACS, AIM, IMEMR and WPIMR from inception to Jan 31, 2015, to identify studies reporting cause of hospital admission in people living with HIV. We focused on data reported after 2007, the period in which access to antiretroviral therapy started to become widespread. We estimated pooled proportions of hospital admissions and deaths per disease category by use of random-effects models. We stratified data by geographical region and age.

Findings: We obtained data from 106 cohorts, with reported causes of hospital admission for  313 006 adults and 6182 children living with HIV. For adults, AIDS-related illnesses (25 119 patients, 46%, 95% CI 40-53) and bacterial infections (14 034 patients, 31%, 20-42) were the leading causes of hospital admission. These two categories were the most common causes of hospital admission for adults in all geographical regions and the most common causes of mortality. Common region-specific causes of hospital admission included malnutrition and wasting, parasitic infections, and haematological disorders in the Africa region; respiratory disease, psychiatric disorders, renal disorders, cardiovascular disorders, and liver disease in Europe; haematological disorders in North America; and respiratory, neurological, digestive and liver-related conditions, viral infections, and drug toxicity in South and Central America. For children, AIDS-related illnesses (783 patients, 27%, 95% CI 19-34) and bacterial infections (1190 patients, 41%, 26-56) were the leading causes of hospital admission, followed by malnutrition and wasting, haematological disorders, and, in the African region, malaria. Mortality in individuals admitted to hospital was 20% (95% CI 18-23, 12 902 deaths) for adults and 14% (10-19, 643 deaths) for children.

Interpretation: This review shows the importance of prompt HIV diagnosis and treatment, and the need to reinforce existing recommendations to provide chemoprophylaxis and vaccination against major preventable infectious diseases to people living with HIV to reduce serious AIDS and non-AIDS morbidity.

Abstract access 

Editor’s notes: Despite the widening availability of antiretroviral therapy (ART), HIV-associated disease remains an important cause of illness and death. In this systematic review the authors summarise published data concerning causes of hospital admission among HIV-positive people since 2007. This date was selected on the basis that access to ART was limited prior to 2007.

Overall the most common causes of admission among adults, across all geographical regions, were AIDS-associated illness and bacterial infections. Tuberculosis was the most common cause among adults, accounting for 18% of all admissions, followed by bacterial pneumonia (15%). Among children, similarly AIDS-associated illnesses (particularly tuberculosis and Pneumocystis pneumonia) and bacterial infections were the most common causes of admission. Among the 20% of adults who died during their admission, the most common causes of death were tuberculosis, bacterial infections, cerebral toxoplasmosis and cryptococcal meningitis. Among children the most common causes of death were tuberculosis, bacterial infections and Pneumocystis pneumonia. Tuberculosis is likely to have been underestimated in these studies. Autopsy studies consistently illustrate that around half of HIV-positive people who have tuberculosis identified at autopsy had not been diagnosed prior to death.

The review highlights that the majority of severe HIV-associated disease remains attributable to advanced immunosuppression. This is reflected by a median CD4 count at admission among adults of 168 cells per µl. Some 30% of people first tested HIV positive at the time of the admission. The review underlines the need to promote HIV testing so that HIV-positive people can access ART, and prevent the complications of advanced HIV disease. It also underscores the need for better coverage of screening for tuberculosis and preventive therapy for people without active disease.  

Avoid TB deaths
Comorbidity, Epidemiology
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START trial illustrates benefit of ART start with CD4>500

Initiation of antiretroviral therapy in early asymptomatic HIV infection.

Lundgren J, Babiker A,  Gordin F, Emery S, Grund B, Sharma S, Avihingsanon A, Cooper D, Fätkenheuer G, Llibre J, Molina J, Munderi P, Schechter M, Wood R, Klingman K, Collins S, Lane H, Phillips A,  Neaton J. INSIGHT START Study Group. N Engl J Med. 2015 Jul 20. [Epub ahead of print]

Background: Data from randomized trials are lacking on the benefits and risks of initiating antiretroviral therapy in patients with asymptomatic human immunodeficiency virus (HIV) infection who have a CD4+ count of more than 350 cells per cubic millimeter.

Methods: We randomly assigned HIV-positive adults who had a CD4+ count of more than 500 cells per cubic millimeter to start antiretroviral therapy immediately (immediate-initiation group) or to defer it until the CD4+ count decreased to 350 cells per cubic millimeter or until the development of the acquired immunodeficiency syndrome (AIDS) or another condition that dictated the use of antiretroviral therapy (deferred-initiation group). The primary composite end point was any serious AIDS-related event, serious non-AIDS-related event, or death from any cause.

Results: A total of 4685 patients were followed for a mean of 3.0 years. At study entry, the median HIV viral load was 12 759 copies per milliliter, and the median CD4+ count was 651 cells per cubic millimeter. On May 15, 2015, on the basis of an interim analysis, the data and safety monitoring board determined that the study question had been answered and recommended that patients in the deferred-initiation group be offered antiretroviral therapy. The primary end point occurred in 42 patients in the immediate-initiation group (1.8%; 0.60 events per 100 person-years), as compared with 96 patients in the deferred-initiation group (4.1%; 1.38 events per 100 person-years), for a hazard ratio of 0.43 (95% confidence interval [CI], 0.30 to 0.62; P<0.001). Hazard ratios for serious AIDS-related and serious non-AIDS-related events were 0.28 (95% CI, 0.15 to 0.50; P<0.001) and 0.61 (95% CI, 0.38 to 0.97; P=0.04), respectively. More than two thirds of the primary end points (68%) occurred in patients with a CD4+ count of more than 500 cells per cubic millimeter. The risks of a grade 4 event were similar in the two groups, as were the risks of unscheduled hospital admissions.

Conclusions: The initiation of antiretroviral therapy in HIV-positive adults with a CD4+ count of more than 500 cells per cubic millimeter provided net benefits over starting such therapy in patients after the CD4+ count had declined to 350 cells per cubic millimeter.

Abstract  Full-text [free] access

Editor’s notes: Guidelines on when to start antiretroviral therapy (ART) are rapidly evolving. The major point of uncertainty, and disagreement between guidelines, has been whether the benefits to individuals of starting ART outweigh the risks for people with high CD4 counts, where the absolute risk of morbidity and mortality is relatively low.

The START study addressed this question among people with CD4 counts greater than 500 cells per µl. Study participants were recruited across the global regions, with the largest number from Europe (33%) followed by Latin America (25%) and Africa (21%). Some 55% were gay men and other men who have sex with men. Retention in the study was very good, and virologic outcomes among people who started ART were excellent (98% and 97% had virologic suppression by 12 months in the immediate versus deferred study arms). There was a 57% reduction in the hazard of the primary outcome, a composite of serious AIDS-associated events, serious non-AIDS associated events or death from any cause. The most common AIDS-associated events were tuberculosis (mostly seen in African participants), malignant lymphoma and Kaposi’s sarcoma. Among the serious non-AIDS events, cancers unrelated to AIDS were reduced by 50%, but interestingly there was no change in cardiovascular events. There was no increase in risk of serious adverse events. Interestingly the magnitude of risk reduction for the primary outcome was similar in high- and low-income countries.

These results will be very important as ART guidelines are reviewed and are likely to lead to recommendations for ART initiation, regardless of CD4 count in most settings. The authors note that, with a relatively low absolute risk of serious events, some people with high CD4 counts may opt to defer treatment, and this trial has produced very useful data to inform this discussion. Benefits from earlier ART initiation are dependent on earlier testing.  With an estimated 50% of people with HIV globally unaware of their status, the uptake of testing by asymptomatic people will need to be increased. In addition, retention in care will need to be optimised if the potential benefits of ART demonstrated by this study are to be realised.

HIV Treatment
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TAF: a new, safer version of tenofovir?

Tenofovir alafenamide versus tenofovir disoproxil fumarate, coformulated with elvitegravir, cobicistat, and emtricitabine, for initial treatment of HIV-1 infection: two randomised, double-blind, phase 3, non-inferiority trials.

Sax PE, Wohl D, Yin MT, Post F, DeJesus E, Saag M, Pozniak A, Thompson M, Podzamczer D, Molina JM, Oka S, Koenig E, Trottier B, Andrade-Villanueva J, Crofoot G, Custodio JM, Plummer A, Zhong L, Cao H, Martin H, Callebaut C, Cheng AK, Fordyce MW, McCallister S, GS-US-292-0104/0111 Study Team. Lancet. 2015 Jun 27;385(9987):2606-15. doi: 10.1016/S0140-6736(15)60616-X. Epub 2015 Apr 15.

Background: Tenofovir disoproxil fumarate can cause renal and bone toxic effects related to high plasma tenofovir concentrations. Tenofovir alafenamide is a novel tenofovir prodrug with a 90% reduction in plasma tenofovir concentrations. Tenofovir alafenamide-containing regimens can have improved renal and bone safety compared with tenofovir disoproxil fumarate-containing regimens.

Methods: In these two controlled, double-blind phase 3 studies, we recruited treatment-naive HIV-infected patients with an estimated creatinine clearance of 50 mL per min or higher from 178 outpatient centres in 16 countries. Patients were randomly assigned (1:1) to receive once-daily oral tablets containing 150 mg elvitegravir, 150 mg cobicistat, 200 mg emtricitabine, and 10 mg tenofovir alafenamide (E/C/F/tenofovir alafenamide) or 300 mg tenofovir disoproxil fumarate (E/C/F/tenofovir disoproxil fumarate) with matching placebo. Randomisation was done by a computer-generated allocation sequence (block size 4) and was stratified by HIV-1 RNA, CD4 count, and region (USA or ex-USA). Investigators, patients, study staff, and those assessing outcomes were masked to treatment group. All participants who received one dose of study drug were included in the primary intention-to-treat efficacy and safety analyses. The main outcomes were the proportion of patients with plasma HIV-1 RNA less than 50 copies per mL at week 48 as defined by the US Food and Drug Administration (FDA) snapshot algorithm (pre-specified non-inferiority margin of 12%) and pre-specified renal and bone endpoints at 48 weeks. These studies are registered with ClinicalTrials.gov, numbers NCT01780506 and NCT01797445.

Findings: We recruited patients from Jan 22, 2013, to Nov 4, 2013 (2175 screened and 1744 randomly assigned), and gave treatment to 1733 patients (866 given E/C/F/tenofovir alafenamide and 867 given E/C/F/tenofovir disoproxil fumarate). E/C/F/tenofovir alafenamide was non-inferior to E/C/F/tenofovir disoproxil fumarate, with 800 (92%) of 866 patients in the tenofovir alafenamide group and 784 (90%) of 867 patients in the tenofovir disoproxil fumarate group having plasma HIV-1 RNA less than 50 copies per mL (adjusted difference 2.0%, 95% CI -0.7 to 4.7). Patients given E/C/F/tenofovir alafenamide had significantly smaller mean serum creatinine increases than those given E/C/F/tenofovir disoproxil fumarate (0.08 vs 0.12 mg/dL; p<0.0001), significantly less proteinuria (median % change -3 vs 20; p<0.0001), and a significantly smaller decrease in bone mineral density at spine (mean % change -1.30 vs -2.86; p<0.0001) and hip (-0.66 vs -2.95; p<0.0001) at 48 weeks.

Interpretation: Through 48 weeks, more than 90% of patients given E/C/F/tenofovir alafenamide or E/C/F/tenofovir disoproxil fumarate had virological success. Renal and bone effects were significantly reduced in patients given E/C/F/tenofovir alafenamide. Although these studies do not have the power to assess clinical safety events such as renal failure and fractures, our data suggest that E/C/F/tenofovir alafenamide will have a favourable long-term renal and bone safety profile.

Abstract access 

Editor’s notes: Tenofovir alafenamide fumarate (TAF) is a new antiretroviral agent developed by Gilead Sciences and is closely related to tenofovir disoproxil fumarate (TDF).  TDF is widely used, highly potent, and safe in the majority of people but long-term use has been associated with small risks of decreased kidney function, chronic kidney disease, and decreased bone mineral density.  Both TAF and TDF are prodrugs of tenofovir but TAF achieves highly potent concentrations of tenofovir inside HIV-relevant immune cells with much lower plasma concentrations than TDF.  The lower plasma concentration of tenofovir associated with TAF is hypothesised to reduce the toxic effects with regards to kidney and bone health. TAF is also effective at the lower dose of 10-25 mg, compared with the standard TDF dose of 300mg per day.  This may translate into lower drug costs if the lower dose required means lower manufacturing costs.

The authors report the combined results of two phase III, non-inferiority studies comparing the safety and effectiveness of TAF with TDF, funded by Gilead Sciences. In both studies, TAF was co-formulated into one, once-a-day tablet with elvitegravir, cobicistat and emtricitabine. There was a high rate of virologic suppression with the TAF-containing regimen, which was non-inferior to the TDF regimen. Compared to TDF, TAF had significantly more favourable effects on renal and bone parameters, with smaller decreases in creatinine clearance and bone mineral density and smaller increases in proteinuria. The real-world clinical significance of these findings remains to be seen but TAF-containing regimens may offer meaningful safety and cost benefits over TDF regimens in the long-term. The favourable characteristics of TAF have also led to the development of a sustained-release subcutaneous TAF implant, which has recently been evaluated in dogs. A long-acting TAF implant could have translational potential as a candidate for HIV prophylaxis in vulnerable populations.

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Can a simple risk score predict chronic kidney disease among people living with HIV?

Development and validation of a risk score for chronic kidney disease in HIV infection using prospective cohort data from the D:A:D study.

Mocroft A, Lundgren JD, Ross M, Law M, Reiss P, Kirk O, Smith C, Wentworth D, Neuhaus J, Fux CA, Moranne O, Morlat P, Johnson MA, Ryom L, D:A:D study group, the Royal Free Hospital Clinic Cohort, and the INSIGHT, SMART, and ESPRIT study groups. PLoS Med. 2015 Mar 31;12(3):e1001809. doi: 10.1371/journal.pmed.1001809. eCollection 2015.

Background: Chronic kidney disease (CKD) is a major health issue for HIV-positive individuals, associated with increased morbidity and mortality. Development and implementation of a risk score model for CKD would allow comparison of the risks and benefits of adding potentially nephrotoxic antiretrovirals to a treatment regimen and would identify those at greatest risk of CKD. The aims of this study were to develop a simple, externally validated, and widely applicable long-term risk score model for CKD in HIV-positive individuals that can guide decision making in clinical practice.

Methods and findings: A total of 17 954 HIV-positive individuals from the Data Collection on Adverse Events of Anti-HIV Drugs (D:A:D) study with ≥3 estimated glomerular filtration rate (eGFR) values after 1 January 2004 were included. Baseline was defined as the first eGFR >60 ml/min/1.73 m2 after 1 January 2004; individuals with exposure to tenofovir, atazanavir, atazanavir/ritonavir, lopinavir/ritonavir, other boosted protease inhibitors before baseline were excluded. CKD was defined as confirmed (>3 mo apart) eGFR ≤60 ml/min/1.73 m2. Poisson regression was used to develop a risk score, externally validated on two independent cohorts. In the D:A:D study, 641 individuals developed CKD during 103 185 person-years of follow-up (PYFU; incidence 6.2/1000 PYFU, 95% CI 5.7-6.7; median follow-up 6.1 y, range 0.3-9.1 y). Older age, intravenous drug use, hepatitis C coinfection, lower baseline eGFR, female gender, lower CD4 count nadir, hypertension, diabetes, and cardiovascular disease (CVD) predicted CKD. The adjusted incidence rate ratios of these nine categorical variables were scaled and summed to create the risk score. The median risk score at baseline was -2 (interquartile range -4 to 2). There was a 1:393 chance of developing CKD in the next 5 y in the low risk group (risk score <0, 33 events), rising to 1:47 and 1:6 in the medium (risk score 0-4, 103 events) and high risk groups (risk score ≥5, 505 events), respectively. Number needed to harm (NNTH) at 5 y when starting unboosted atazanavir or lopinavir/ritonavir among those with a low risk score was 1702 (95% CI 1166-3367); NNTH was 202 (95% CI 159-278) and 21 (95% CI 19-23), respectively, for those with a medium and high risk score. NNTH was 739 (95% CI 506-1462), 88 (95% CI 69-121), and 9 (95% CI 8-10) for those with a low, medium, and high risk score, respectively, starting tenofovir, atazanavir/ritonavir, or another boosted protease inhibitor. The Royal Free Hospital Clinic Cohort included 2548 individuals, of whom 94 individuals developed CKD (3.7%) during 18 376 PYFU (median follow-up 7.4 y, range 0.3-12.7 y). Of 2013 individuals included from the SMART/ESPRIT control arms, 32 individuals developed CKD (1.6%) during 8452 PYFU (median follow-up 4.1 y, range 0.6-8.1 y). External validation showed that the risk score predicted well in these cohorts. Limitations of this study included limited data on race and no information on proteinuria.

Conclusions: Both traditional and HIV-related risk factors were predictive of CKD. These factors were used to develop a risk score for CKD in HIV infection, externally validated, that has direct clinical relevance for patients and clinicians to weigh the benefits of certain antiretrovirals against the risk of CKD and to identify those at greatest risk of CKD.

Abstract  Full-text [free] access

Editor’s notes: The nephrotoxicity of antiretroviral drugs, particularly tenofovir, is of concern, particularly where there is limited access to laboratory monitoring of kidney function. The development of kidney impairment among people with HIV is associated with poor outcomes, and in low resource settings where dialysis is not available this can be catastrophic.

This study, like previous work, attempts to address this problem by developing a risk score for the development of chronic kidney disease (CKD). The strength of this study is the availability of data for over 17 000 men and women living with HIV enrolled in cohort studies for many years, and in over 40 countries globally. The resulting risk score uses nine simple clinical variables which predict CKD both overall, and after starting potentially nephrotoxic antiretrovirals. A short risk score, not including cardiovascular risk factors, which may be more suitable for low resource settings, shows almost as good a prediction of CKD.

So will this risk score become widely used in clinical decision making? For high income countries this tool may be useful to identify people where strategies to prevent cardiovascular and renal disease are best focussed. It may also be useful to identify people at high risk of developing CKD for whom use of tenofovir may be unacceptable, especially when monitoring of kidney function is limited. However, few of the enrolled people were from low and middle income countries, and there was limited information on the race of participants. Therefore, the risk score may need to be validated in low resource settings before it can be widely used. Whether the use of the tool would help to improve clinical outcomes where kidney function is frequently monitored is unclear.

Meanwhile, a new drug formulation, tenofovir alafenamide (TAF), is currently in clinical trials. This appears to be associated with less renal toxicity, and to be safe and well tolerated among adults with decreased kidney function. If future trial results support this evidence, and tenofovir alafenamide becomes widely available, concern about drug nephrotoxicity may become a less pressing clinical issue.

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