Decreased frequency of CD73+CD8+ T cells of HIV-infected patients correlates with immune activation and T cell exhaustion

Recent studies indicate that murine Tregs highly express the ENTDP1, as well as the 5'-NT and thereby, suppress Teff function by extracellular adenosine production. Furthermore, CD73 seems to play a role as costimulatory molecule for T cell differentiation. In this study, we analyzed the expression of CD73 on peripheral and lymph nodal Teffs and Tregs in a cohort of 95 HIV patients at different stages of disease, including LTNP and ECs. In contrast to murine Tregs, CD73 was only expressed on a small minority (∼10%) of peripheral Tregs. In contrast, we see high expression of CD73 on peripheral CD8(+) T cells. In HIV infection, CD73 is markedly reduced on all Teffs and Tregs, regardless of the memory subtype. On CD8(+) T cells, a positive correlation between CD73 expression and CD4 counts (P=0.0003) was detected. CD73 expression on CD8(+) T cells negatively correlated with HLA-DR (<0.0001) and PD1 (P=0.0457) expression. The lower CD73 expression on CD8(+) T cells was partially reversible after initiation of ART (P=0.0016). Functionally, we observed that CD8(+)CD73(+) T cells produce more IL-2 upon HIV-specific and unspecific stimulation than their CD73(-) counterparts and show a higher proliferative capacity. These data indicate that down-regulation of CD73 on CD8(+) T cells correlates with immune activation and leads to functional deficits in HIV infection.

Cohort profile: Antiretroviral Therapy Cohort Collaboration (ART-CC)

The advent of effective combination antiretroviral therapy (ART) in 1996 resulted in fewer patients experiencing clinical events, so that some prognostic analyses of individual cohort studies of human immunodeficiency virus-infected individuals had low statistical power. Because of this, the Antiretroviral Therapy Cohort Collaboration (ART-CC) of HIV cohort studies in Europe and North America was established in 2000, with the aim of studying the prognosis for clinical events in acquired immune deficiency syndrome (AIDS) and the mortality of adult patients treated for HIV-1 infection. In 2002, the ART-CC collected data on more than 12,000 patients in 13 cohorts who had begun combination ART between 1995 and 2001. Subsequent updates took place in 2004, 2006, 2008, and 2010. The ART-CC data base now includes data on more than 70,000 patients participating in 19 cohorts who began treatment before the end of 2009. Data are collected on patient demographics (e.g. sex, age, assumed transmission group, race/ethnicity, geographical origin), HIV biomarkers (e.g. CD4 cell count, plasma viral load of HIV-1), ART regimen, dates and types of AIDS events, and dates and causes of death. In recent years, additional data on co-infections such as hepatitis C; risk factors such as smoking, alcohol and drug use; non-HIV biomarkers such as haemoglobin and liver enzymes; and adherence to ART have been collected whenever available. The data remain the property of the contributing cohorts, whose representatives manage the ART-CC via the steering committee of the Collaboration. External collaboration is welcomed. Details of contacts are given on the ART-CC website (www.art-cohort-collaboration.org).

Contribution of genetic background, traditional risk factors, and HIV-related factors to coronary artery disease events in HIV-positive persons

BACKGROUND

Persons infected with human immunodeficiency virus (HIV) have increased rates of coronary artery disease (CAD). The relative contribution of genetic background, HIV-related factors, antiretroviral medications, and traditional risk factors to CAD has not been fully evaluated in the setting of HIV infection.

METHODS

In the general population, 23 common single-nucleotide polymorphisms (SNPs) were shown to be associated with CAD through genome-wide association analysis. Using the Metabochip, we genotyped 1875 HIV-positive, white individuals enrolled in 24 HIV observational studies, including 571 participants with a first CAD event during the 9-year study period and 1304 controls matched on sex and cohort.

RESULTS

A genetic risk score built from 23 CAD-associated SNPs contributed significantly to CAD (P = 2.9 × 10(-4)). In the final multivariable model, participants with an unfavorable genetic background (top genetic score quartile) had a CAD odds ratio (OR) of 1.47 (95% confidence interval [CI], 1.05-2.04). This effect was similar to hypertension (OR = 1.36; 95% CI, 1.06-1.73), hypercholesterolemia (OR = 1.51; 95% CI, 1.16-1.96), diabetes (OR = 1.66; 95% CI, 1.10-2.49), ≥ 1 year lopinavir exposure (OR = 1.36; 95% CI, 1.06-1.73), and current abacavir treatment (OR = 1.56; 95% CI, 1.17-2.07). The effect of the genetic risk score was additive to the effect of nongenetic CAD risk factors, and did not change after adjustment for family history of CAD.

CONCLUSIONS

In the setting of HIV infection, the effect of an unfavorable genetic background was similar to traditional CAD risk factors and certain adverse antiretroviral exposures. Genetic testing may provide prognostic information complementary to family history of CAD.

[Morbidity and mortality conferences in internal medicine--experience at the University Hospital of Cologne]

Morbidity and mortality (M&M) conferences serve as a forum for the discussion of adverse events and errors in the treatment of patients. In the United States M&M conferences are an established part of medical training programs. While being state of the art in specialities like surgery and anesthesiology, they were established later on in internal medicine. To date, no reports have been published on M&M conferences in departments of internal medicine in Germany. Since August 2010 a morbidity and mortality conference takes place once per month in the Department I of Internal Medicine of the university hospital of Cologne. Cases with unexpected death, unexpected complications or medical errors are discussed. The primary goal is to create an open and confidential forum for doctors, where errors can be discussed without any assignment of guilt. The uncovering of structural problems frequently leads to direct improvements in patient care. Furthermore, the conference can play an important role in medical education.

Risk factors and outcomes for late presentation for HIV-positive persons in Europe: results from the Collaboration of Observational HIV Epidemiological Research Europe Study (COHERE)

BACKGROUND

Few studies have monitored late presentation (LP) of HIV infection over the European continent, including Eastern Europe. Study objectives were to explore the impact of LP on AIDS and mortality.

METHODS AND FINDINGS

LP was defined in Collaboration of Observational HIV Epidemiological Research Europe (COHERE) as HIV diagnosis with a CD4 count <350/mm(3) or an AIDS diagnosis within 6 months of HIV diagnosis among persons presenting for care between 1 January 2000 and 30 June 2011. Logistic regression was used to identify factors associated with LP and Poisson regression to explore the impact on AIDS/death. 84,524 individuals from 23 cohorts in 35 countries contributed data; 45,488 were LP (53.8%). LP was highest in heterosexual males (66.1%), Southern European countries (57.0%), and persons originating from Africa (65.1%). LP decreased from 57.3% in 2000 to 51.7% in 2010/2011 (adjusted odds ratio [aOR] 0.96; 95% CI 0.95-0.97). LP decreased over time in both Central and Northern Europe among homosexual men, and male and female heterosexuals, but increased over time for female heterosexuals and male intravenous drug users (IDUs) from Southern Europe and in male and female IDUs from Eastern Europe. 8,187 AIDS/deaths occurred during 327,003 person-years of follow-up. In the first year after HIV diagnosis, LP was associated with over a 13-fold increased incidence of AIDS/death in Southern Europe (adjusted incidence rate ratio [aIRR] 13.02; 95% CI 8.19-20.70) and over a 6-fold increased rate in Eastern Europe (aIRR 6.64; 95% CI 3.55-12.43).

CONCLUSIONS

LP has decreased over time across Europe, but remains a significant issue in the region in all HIV exposure groups. LP increased in male IDUs and female heterosexuals from Southern Europe and IDUs in Eastern Europe. LP was associated with an increased rate of AIDS/deaths, particularly in the first year after HIV diagnosis, with significant variation across Europe. Earlier and more widespread testing, timely referrals after testing positive, and improved retention in care strategies are required to further reduce the incidence of LP.

Predictors of CD4(+) T-cell counts of HIV type 1-infected persons after virologic failure of all 3 original antiretroviral drug classes

BACKGROUND

Low CD4(+) T-cell counts are the main factor leading to clinical progression in human immunodeficiency virus type 1 (HIV-1) infection. We aimed to investigate factors affecting CD4(+) T-cell counts after triple-class virological failure.

METHODS

We included individuals from the COHERE database who started antiretroviral therapy from 1998 onward and who experienced triple-class virological failure. CD4(+) T-cell counts obtained after triple-class virologic failure were analyzed using generalized estimating equations.

RESULTS

The analyses included 2424 individuals with a total of 23 922 CD4(+) T-cell count measurements. In adjusted models (excluding current viral load and year), CD4(+) T-cell counts were higher with regimens that included boosted protease inhibitors (increase, 22 cells/µL [95% confidence interval {CI}, 3.9-41]; P = .017) or drugs from the new classes (increase, 39 cells/µL [95% CI, 15-62]; P = .001), compared with nonnucleoside reverse-transcriptase inhibitor-based regimens. These associations disappeared when current viral load and/or calendar year were included. Compared with viral levels of <2.5 log(10) copies/mL, levels of 2.5-3.5, 3.5-4.5, 4.5-5.5, and >5.5 log(10) copies/mL were associated with CD4(+) T-cell count decreases of 51, 84, 137, and 186 cells/µL, respectively (P < .001).

CONCLUSIONS

The approximately linear inverse relationship between log(10) viral load and CD4(+) T-cell count indicates that there are likely immunologic benefits from lowering viral load even by modest amounts that do not lead to undetectable viral loads. This is important for patients with low CD4(+) T-cell counts and few drug options.

Stage-adapted treatment of HIV-associated Hodgkin lymphoma: results of a prospective multicenter study

PURPOSE

Although the outcome of patients with HIV-related Hodgkin lymphoma (HIV-HL) has markedly improved since the introduction of combined antiretroviral therapy, standard therapy is still poorly defined. This prospective study investigates a stage- and risk-adapted treatment strategy in patients with HIV-HL.

PATIENTS AND METHODS

Patients with early favorable HIV-HL received two to four cycles of doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD) followed by 30 Gy of involved-field (IF) radiation. In patients with early unfavorable HIV-HL, four cycles of bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisone (BEACOPP baseline) or four cycles of ABVD + 30 Gy of IF radiation were administered. Six to eight cycles of BEACOPP baseline were given in patients with advanced-stage HIV-HL. In patients with advanced HIV infection, BEACOPP was replaced with ABVD.

RESULTS

Of 108 patients (including eight female patients) included in the study, 23 (21%) had early favorable HL, 14 (13%) had early unfavorable HL, and 71 (66%) had advanced-stage HL. The median CD4 count at HL diagnosis was 240/μL. The complete remission rates for patients with early favorable, early unfavorable, and advanced-stage HL were 96%, 100%, and 86%, respectively. The 2-year progression-free survival of the entire study population was 91.7%. Eleven patients (11%) have died, and treatment-related mortality was 5.6%. The 2-year overall survival rate was 90.7% with no significant difference between early favorable (95.7%), early unfavorable (100%), and advanced-stage HL (86.8%).

CONCLUSION

In patients with HIV-HL, stage- and risk-adapted treatment is feasible and effective. The prognosis for patients with HIV-HL may approach that of HIV-negative patients with HL.

Mucormycosis treated with posaconazole: review of 96 case reports

Mucormycosis is an emerging invasive fungal infection, primarily affecting immunocompromised patients. The disease is difficult to diagnose and mortality reaches 40% even if treated adequately. Depending on site of infection and risk factors, surgical debridement in combination with systemically active antifungal drugs are the mainstay treatment strategies. Lipid-based amphotericin B is the treatment of choice for first-line therapy while posaconazole may be a promising alternative. We performed a PubMed search on reports of patients with mucormycosis treated with posaconazole. From 2003 to 2011, 96 cases have been published. Diagnosis was based on histology alone in 2 (2.1%) and microbiological evidence in 67 (69.8%), while no data on the diagnostic approach was reported in 27 (28.1%) patients. The most frequent pathogens were Rhizopus spp. (31.2%), followed by Mucor spp. (14.6%). The site of infection was predominantly rhino-orbital (38.5%, of which 43% also had central nervous system [CNS] involvement), followed by disseminated disease (22.1%). A complete response was achieved in 62 (64.6%), partial response in 7 (7.3%) patients, and stable disease in 1 (1%). Overall mortality was 24% (lacking data for three patients). In published case reports on posaconazole treatment for mucormycosis, the drug was frequently and successfully used in combination or as second line therapy.

Organic cation transporters OCT1 and OCT2 determine the accumulation of lamivudine in CD4 cells of HIV-infected patients

PURPOSE

Identifying factors that determine concentrations of antiretroviral drugs in CD4 cells are important for improving therapeutic efficacy. Experimental models indicate that the nucleoside reverse transcriptase inhibitor lamivudine is transported by the organic cation transporters 1 and 2 (OCT1 and OCT2, respectively). Here, we tested whether OCT1 and OCT2 contribute to the uptake of lamivudine into native CD4 cells of human immunodeficiency virus (HIV)-infected individuals.

METHODS

CD4 cells obtained by non-activated cell sorting from 35 individuals with HIV-1 infection were incubated with lamivudine (10 μM, 30 min), and intracellular concentrations of lamivudine and its active metabolite lamivudine triphosphate were determined by liquid chromatography tandem mass spectrometry. The expression of OCT1 and OCT2 mRNA was measured by quantitative real-time polymerase chain reaction (PCR). A model of OCT2-transfected CD4 cells was established for mechanistic investigations.

RESULTS

Intracellular concentrations of lamivudine and its active metabolite lamivudine triphosphate showed strong linear correlations with each other and with the CD4 mRNA expression of OCT1 and OCT2 (r > 0.80). Coincubation with protease inhibitors (ritonavir, nelfinavir) that inhibit OCT1 and OCT2 yielded decreased intracellular concentrations of lamivudine and lamivudine triphosphate. Incubation of CD4 cells from healthy donors transfected with an OCT2 expression vector yielded increased concentrations of lamivudine and lamivudine triphosphate.

CONCLUSION

Our studies indicate a role of OCT1 and OCT2 for the cellular accumulation of lamivudine in HIV-infected individuals.

Broad neutralization by a combination of antibodies recognizing the CD4 binding site and a new conformational epitope on the HIV-1 envelope protein

A new method is used to isolate neutralizing antibodies recognizing a new epitope on the cell surface–expressed, but not soluble, HIV-1 spike.

Two to three years after infection, a fraction of HIV-1–infected individuals develop serologic activity that neutralizes most viral isolates. Broadly neutralizing antibodies that recognize the HIV-1 envelope protein have been isolated from these patients by single-cell sorting and by neutralization screens. Here, we report a new method for anti–HIV-1 antibody isolation based on capturing single B cells that recognize the HIV-1 envelope protein expressed on the surface of transfected cells. Although far less efficient than soluble protein baits, the cell-based capture method identified antibodies that bind to a new broadly neutralizing epitope in the vicinity of the V3 loop and the CD4-induced site (CD4i). The new epitope is expressed on the cell surface form of the HIV-1 spike, but not on soluble forms of the same envelope protein. Moreover, the new antibodies complement the neutralization spectrum of potent broadly neutralizing anti-CD4 binding site (CD4bs) antibodies obtained from the same individual. Thus, combinations of potent broadly neutralizing antibodies with complementary activity can account for the breadth and potency of naturally arising anti–HIV-1 serologic activity. Therefore, vaccines aimed at eliciting anti–HIV-1 serologic breadth and potency should not be limited to single epitopes.

Considerations in the rationale, design and methods of the Strategic Timing of AntiRetroviral Treatment (START) study

BACKGROUND

Untreated human immunodeficiency virus (HIV) infection is characterized by progressive depletion of CD4+ T lymphocyte (CD4) count leading to the development of opportunistic diseases (acquired immunodeficiency syndrome (AIDS)), and more recent data suggest that HIV is also associated with an increased risk of serious non-AIDS (SNA) diseases including cardiovascular, renal, and liver diseases and non-AIDS-defining cancers. Although combination antiretroviral treatment (ART) has resulted in a substantial decrease in morbidity and mortality in persons with HIV infection, viral eradication is not feasible with currently available drugs. The optimal time to start ART for asymptomatic HIV infection is controversial and remains one of the key unanswered questions in the clinical management of HIV-infected individuals.

PURPOSE

In this article, we outline the rationale and methods of the Strategic Timing of AntiRetroviral Treatment (START) study, an ongoing multicenter international trial designed to assess the risks and benefits of initiating ART earlier than is currently practiced. We also describe some of the challenges encountered in the design and implementation of the study and how these challenges were addressed.

METHODS

A total of 4000 study participants who are HIV type 1 (HIV-1) infected, ART naïve with CD4 count > 500 cells/µL are to be randomly allocated in a 1:1 ratio to start ART immediately (early ART) or defer treatment until CD4 count is <350 cells/µL (deferred ART) and followed for a minimum of 3 years. The primary outcome is time to AIDS, SNA, or death. The study had a pilot phase to establish feasibility of accrual, which was set as the enrollment of at least 900 participants in the first year.

RESULTS

Challenges encountered in the design and implementation of the study included the limited amount of data on the risk of a major component of the primary endpoint (SNA) in the study population, changes in treatment guidelines when the pilot phase was well underway, and the complexities of conducting the trial in a geographically wide population with diverse regulatory requirements. With the successful completion of the pilot phase, more than 1000 participants from 100 sites in 23 countries have been enrolled. The study will expand to include 237 sites in 36 countries to reach the target accrual of 4000 participants.

CONCLUSIONS

START is addressing one of the most important questions in the clinical management of ART. The randomization provided a platform for the conduct of several substudies aimed at increasing our understanding of HIV disease and the effects of antiretroviral therapy beyond the primary question of the trial. The lessons learned from its design and implementation will hopefully be of use to future publicly funded international trials.

Liver involvement in HIV-infected patients diagnosed with syphilis

PURPOSE

Liver involvement in syphilis has been studied in cohorts of human immunodeficiency virus (HIV)-negative individuals despite the scarcity of data on such HIV-infected patients. Th aim of this study was to assess hepatic involvement of HIV-infected patients diagnosed with syphilis.

METHODS

Patients with syphilis and liver involvement, including all stages of syphilis, were systematically identified in our HIV cohort between 2004 and 2008.

RESULTS

Of the 1,599 HIV-infected patients identified during the study period, 100 were diagnosed with acute syphilis, all of whom were male. Of these 100 patients, 84% were men who have sex with men. Laboratory parameters of liver involvement were present in 19 of the 100 HIV-infected patients with syphilis; these resolved after successful antibiotic treatment. Among these 19 patients, six were diagnosed to be in the latent stage, with elevated liver enzymes and parameters of inflammation representing the only distinctive feature.

CONCLUSIONS

Based on our results, syphilis should be included in the differential diagnosis of increased liver enzymes in HIV-infected patients.

Infectious diseases publications in leading medical journals--a comparative analysis

The representation of medical disciplines in leading journals may provide valuable information on their respective importance for both researchers and funding agencies. We were interested in the scientific contribution of infectious diseases to leading medical journals and their ranking compared to other medical disciplines. Original articles and short communications in three leading medical journals from 2003 to 2009 were analyzed by contributing medical discipline and by nation: The New England Journal of Medicine (NEJM), The Lancet, and the Journal of the American Medical Association (JAMA). The medical disciplines were selected according to a standard textbook (Harrison's Principles of Internal Medicine). Each article was categorized into one to three medical disciplines. The most frequently represented disciplines in 3,953 articles were cardiology (19.5 %), infectious diseases (18.6 %), and hematology/oncology (15.9 %). Each of the journals had another leading discipline: cardiology in JAMA, hematology/oncology in NEJM, and infectious diseases in The Lancet. In the American journals, contributions from US researchers dominated the field (52.6 % in NEJM, 73.6 % in JAMA), while the majority of papers in The Lancet originated from non-US residents (76.5 %). This study underlines the importance of infectious diseases as a medical discipline in clinical research.

[Vaccination against rabies: how and when?]

Each year, more than 55,000 people die from rabies. Rabies virus (RABV) is transmitted via bites from infected animals. Dogs represent the most important source of infections worldwide. In Germany, the last case of terrestrial rabies was reported in 2006. Therefore, the country has been considered rabies-free since September 2008 (as defined by World Organization of Animal Health, OIE). Bat rabies, however, is still endemic and mostly occurs in northern Germany. It is caused by the European Bat Lyssa Virus (EBLV), which is closely related to RABV. Cases of rabies in humans are almost 100 % lethal, therefore, the correct choice of prophylactic measures is essential. Pre-exposition vaccination is recommended for individuals at risk of contact to Rabies Virus. If used together with post-exposure measures, it confers high-grade protection against disease manifestation. Even non-vaccinated individuals exposed to Rabies Virus can be protected from overt disease in almost all cases with timely and accurate application of post-exposure vaccination. The mode and intensity of exposure determine the choice of regimen (wound treatment, active and passive vaccination).

Long-term beneficial effect of protease inhibitors on the intrinsic apoptosis of peripheral blood mononuclear cells in HIV-infected patients

BACKGROUND

Viral suppression by antiretroviral therapy (ART) inhibits HIV-induced apoptosis and CD4 T-cell loss. It has been suggested that protease inhibitors (PIs) have nonviral antiapoptotic effects by maintaining mitochondrial integrity. Long-term clinical effects of PI-based ART on mitochondrial toxicity and lymphocyte apoptosis beyond viral suppression have not been exploited to date.

METHODS

We conducted a 7-year study on HIV-1-infected patients from the Cologne HIV cohort with sufficient viral suppression under either a PI-based or nonnucleoside reverse transcriptase inhibitor (NNRTI)-based regimen. Eight patients on PI and eight on NNRTI were eligible for inclusion in the analysis. The primary outcome measure was defined as a change in the mitochondrial-to-nuclear DNA ratio in PBMCs. Further key molecules involved in extrinsic [tumour necrosis factor-related apoptosis-inducing ligand (TRAIL), Fas ligand (FasL) and caspase 8], intrinsic [B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X protein (Bax), caspase 9 and lactate-to-pyruvate ratio] and overall apoptosis [Annexin+/7-aminoactinomycin D (7-AAD)- and caspase 3/7] and viral activity [negative regulatory factor (Nef), interferon-α (IFN-α) and myxovirus resistance protein A (MxA)] were measured.

RESULTS

Demographic and baseline clinical parameters were similar in the two groups, except that patients in the PI group had a higher mean age. After 7 years of treatment, CD4 T-cell count increased and the expression of genes encoding the proapoptotic viral protein Nef and HIV-induced cytokine IFN-α and its downstream effector MxA decreased in both groups. Focusing on the different pathways of apoptosis, only in the PI group intrinsic apoptosis decreased significant and in the inter-group comparison the decrease was significantly higher than in the NNRTI group.

CONCLUSIONS

Our study provides evidence that long-term therapy with a PI-based regimen may be superior to that with a NNRTI-based regimen with regard to its intrinsic antiapoptotic effect.

Epidemiology of transmitted drug resistance in chronically HIV-infected patients in Germany: the RESINA study 2001-2009

OBJECTIVES

Transmitted HIV drug resistance may impair treatment efficacy of combination antiretroviral therapy (ART). This study describes the epidemiology of transmitted resistance in chronically infected patients.

METHODS

In a prospective multicenter trial in Nordrhein-Westfalen, Germany, transmitted drug resistance was determined by genotypic resistance testing in patients on initiation of first-line ART.

RESULTS

From 2001 to 2009, 2,078 patients were enrolled in the study. 79.9% were male, 81.2% were Caucasians, and a homosexual transmission mode was found in 51.3%. Of these patients, 41.5% were at the stage of AIDS, median CD4 cell count was 230/μl, and median viral load was 64.466 copies/ml. Transmitted drug resistance mutations were seen in 9.2% (95% CI, 7.9-10.4). Resistance in the nucleoside reverse transcriptase inhibitor class was found in 5.8% (4.8-6.8), in the nonnucleoside reverse transcriptase inhibitor class in 2.8% (2.1-3.6), and in the protease inhibitor class in 2.7% (2.0-3.4). After a continuous increase to a level above 10% in the years 2006 and 2007, a decline of drug resistance prevalence followed in 2008 and 2009.

CONCLUSIONS

Transmitted HIV drug resistance was found in around 10% of chronically infected patients in Germany who started their ART. We showed a moderate decline of the prevalence of mutant virus strains in recent years. Further surveillance of this phenomenon is mandatory.

Prediction of HIV-1 coreceptor usage (tropism) by sequence analysis using a genotypic approach

Maraviroc (MVC) is the first licensed antiretroviral drug from the class of coreceptor antagonists. It binds to the host coreceptor CCR5, which is used by the majority of HIV strains in order to infect the human immune cells (Fig. 1). Other HIV isolates use a different coreceptor, the CXCR4. Which receptor is used, is determined in the virus by the Env protein (Fig. 2). Depending on the coreceptor used, the viruses are classified as R5 or X4, respectively. MVC binds to the CCR5 receptor inhibiting the entry of R5 viruses into the target cell. During the course of disease, X4 viruses may emerge and outgrow the R5 viruses. Determination of coreceptor usage (also called tropism) is therefore mandatory prior to administration of MVC, as demanded by EMA and FDA. The studies for MVC efficiency MOTIVATE, MERIT and 1029 have been performed with the Trofile assay from Monogram, San Francisco, U.S.A. This is a high quality assay based on sophisticated recombinant tests. The acceptance for this test for daily routine is rather low outside of the U.S.A., since the European physicians rather tend to work with decentralized expert laboratories, which also provide concomitant resistance testing. These laboratories have undergone several quality assurance evaluations, the last one being presented in 2011. For several years now, we have performed tropism determinations based on sequence analysis from the HIV env-V3 gene region (V3). This region carries enough information to perform a reliable prediction. The genotypic determination of coreceptor usage presents advantages such as: shorter turnover time (equivalent to resistance testing), lower costs, possibility to adapt the results to the patients' needs and possibility of analysing clinical samples with very low or even undetectable viral load (VL), particularly since the number of samples analysed with VL < 1000 copies/μl roughly increased in the last years (Fig. 3). The main steps for tropism testing (Fig. 4) demonstrated in this video: Collection of a blood sample Isolation of the HIV RNA from the plasma and/or HIV proviral DNA from blood mononuclear cells Amplification of the env region Amplification of the V3 region Sequence reaction of the V3 amplicon Purification of the sequencing samples Sequencing the purified samples Sequence editing Sequencing data interpretation and tropism prediction.

Trends in virological and clinical outcomes in individuals with HIV-1 infection and virological failure of drugs from three antiretroviral drug classes: a cohort study

BACKGROUND

Limited treatment options have been available for people with HIV who have had virological failure of the three original classes of HIV antiretroviral drugs-so-called triple-class virological failure (TCVF). However, introduction of new drugs and drug classes might have improved outcomes. We aimed to assess trends in virological and clinical outcomes for individuals with TCVF in 2000-09.

METHODS

In our cohort study, we analysed data for adults starting antiretroviral therapy from 1998 in cohorts participating in the PLATO II project, which is part of COHERE, a collaboration of European cohorts. TCVF was defined as virological failure to at least two nucleoside reverse transcriptase inhibitors, one non-nucleoside reverse-transcriptase inhibitor, and one ritonavir-boosted protease inhibitor, with virological failure of a drug defined as one viral-load measurement of greater than 500 copies per mL after at least 4 months of continuous use. We used multivariable generalised estimating equation logistic models and Poisson regression models to study trends in virological suppression and incidence of AIDS or death after TCVF. We adjusted for sex, transmission group, age, AIDS status, CD4 cell count, plasma viral loads at TCVF, achievement of virological response (<50 copies per mL), and number of drug failures before TCVF.

FINDINGS

28 of 33 cohorts in COHERE contributed data to the PLATO II project, of which four had no participants eligible for inclusion in this study. 2476 (3%) of 91 764 participants from the remaining 24 cohorts had TCVF and at least one viral load measurement in 2000-09. The proportion of patients with virological response after TCVF increased from 19·5% in 2000 to 57·9% in 2009 (adjusted p<0·0001). Incidence of AIDS decreased from 7·7 per 100 person-years in 2000-02 to 2·3 in 2008 and 1·2 in 2009 (adjusted p<0·0001). Mortality decreased from 4·0 per 100 person-years between 2000 and 2002 to 1·9 in 2007 and 1·4 in 2008 (unadjusted p=0·023), but the trend was not significant after adjustment (p=0·22).

INTERPRETATION

A substantial improvement in viral load suppression and accompanying decrease in the rates of AIDS in people after extensive failure to drugs from the three original antiretroviral classes during 2000-09 was probably mainly driven by availability of newer drugs with better tolerability and ease of use and small cross-resistance profiles, suggesting the public health benefit of the introduction of new drugs.