Pavel Khaykin

Causes of death in HIV-1-infected patients treated with antiretroviral therapy, 1996-2006: collaborative analysis of 13 HIV cohort studies

BACKGROUND We examined specific causes of mortality in human immunodeficiency virus type 1 (HIV-1)-infected patients who initiated antiretroviral therapy (ART) in Europe and North America from 1996 through 2006, and we quantified associations of prognostic factors with cause-specific mortality. METHODS We retrospectively classified all deaths among 39,272 patients enrolled in 13 HIV-1 cohorts (154,667 person years of follow-up) into the categories specified in the Cause of Death (CoDe) project protocol. RESULTS In 1597 (85%) of 1876 deaths, a definitive cause of death could be assigned. Among these, 792 deaths (49.5%) were AIDS related, followed by non-AIDS malignancies (189; 11.8%), non-AIDS infections (131; 8.2%), violence- and/or drug-related causes (124; 7.7%), liver disease (113; 7.0%), and cardiovascular disease (103; 6.5%). Rates of AIDS-related death (hazard ratio [HR] per 100 cell decrease, 1.43; 95% confidence interval [CI], 1.34-1.53) and death from renal failure (HR, 1.73; 95% CI, 1.18-2.55) were strongly inversely related to CD4 count at initiation of ART, whereas rates of death attributable to AIDS (HR for viral load >5 vs 5 log copies/mL, 1.31; 95% CI, 1.12-1.53), infection (HR, 1.85; 95% CI, 1.25-2.73), cardiovascular (HR, 1.54; 95% CI, 1.05-2.27), and respiratory causes (HR, 3.62; 95% CI, 1.30-10.09) were higher in patients with baseline viral load >5 log copies/mL than in other patients. Rates of each cause of death were higher in patients with presumed transmission via injection drug use than in other patients, with marked increases in rates of liver-related (HR for injection drug use vs non-injection drug use, 6.06; 95% CI, 4.03-9.09) and respiratory tract-related (HR, 4.94; 95% CI, 1.96-12.45) mortality. The proportion of deaths classified as AIDS related decreased with increasing duration of ART. CONCLUSIONS Important contributors to non-AIDS mortality in treated HIV-1-infected individuals must be addressed if decreases in mortality rates are to continue.

Comprehensive Analysis of Frequency and Phenotype of T Regulatory Cells in HIV Infection: CD39 expression of FoxP3+ T regulatory cells correlates with progressive disease.

ABSTRACT There are conflicting data about the frequency and role of regulatory T cells (Tregs) during the course of HIV infection. Peripheral blood of a large cohort of HIV-infected patients (n = 131) at different stages of disease, including 15 long-term nonprogressors and 21 elite controllers, was analyzed to determine the frequency and phenotype of Tregs, defined as CD4+, CD25high, CD127low, FoxP3high cells. A significantly increased relative frequency of Tregs within the CD4+ compartment of HIV+ patients compared to that of healthy controls (P < 0.0001) was observed. Additionally, the relative frequency of Tregs directly correlated with HIV viral load and inversely with CD4+ counts. However, the absolute Treg number was reduced in HIV-infected patients versus healthy controls (P < 0.0001), with the exception of elite controllers (P > 0.05). The loss of absolute Treg numbers coincided with rising markers of immune activation (P < 0.0006). The initiation of antiviral therapy significantly increased absolute Treg numbers (P < 0.0031). We find that the expression of CD39, a newly defined ectonucleotidase with immunomodulatory functions on Tregs, correlated with progressive HIV disease, HIV viral load, and immune activation. Of note, when tested in peripheral blood mononuclear cells of healthy volunteers, the in vitro capacity to suppress T-cell proliferation was limited to CD4+, CD25high, CD39+ T cells. Interestingly, Tregs of elite controllers exhibited not only the highest expression of CCR5, CTLA-4, and ICOS but also the lowest level of CD39. The data presented here reconcile the seemingly contradictory results of previous studies looking at Tregs in HIV and highlight the complexity of Treg-mediated immunoregulation during human viral infections.

Immune Response after Two Doses of the Novel Split Virion, Adjuvanted Pandemic H1N1 Influenza A Vaccine in HIV-1–Infected Patients

BACKGROUND To determine the rate of seroconversion after 2 doses of a novel split virion, inactivated, adjuvanted pandemic H1N1 influenza vaccine (A/California/7/2009) in human immunodeficiency virus type 1 (HIV-1)-infected patients (ClinicalTrials.gov NCT01017172). METHODS Diagnostic study of adult HIV-1-infected patients scheduled for H1N1 influenza A vaccination. Blood samples where taken before and 21 days after the first dose and 21 days after the second dose of the vaccine. Antibody (AB) titers were determined by hemagglutination inhibition assay. Seroconversion was defined by either an AB titer ≤ 1:10 before and ≥ 1:40 after or ≥ 1:10 before and a ≥ 4-fold increase in AB titer 21 days after vaccination. RESULTS One hundred thirty-five patients received 2 doses of the H1N1 vaccine and were analyzed. The rate of seroconversion was 68.2% (95% confidence interval, 59.6-75.9) after the first dose and 91.9% (95% confidence interval, 85.9-95.9) after the second dose. Patients who did not seroconvert had a lower mean nadir CD4 cell count (± standard deviation; 81 ± 99 vs 190 ± 148 cells/μL; P = .006), had a longer duration of HIV infection (± standard deviation; 13.1 ± 5.9 vs 8.8 ± 6.8 years; P = .04), and were more likely to have an AB titer ≥ 1:40 before vaccination (4% vs 55%; P < .001) when compared with patients with seroconversion. No other differences were found between the 2 groups, including AIDS status, highly active antiretroviral therapy status, HIV RNA - polymerase chain reaction load <50 copies/mL, CD4 cell count, sex, body mass index, and chronic hepatitis. CONCLUSION Among HIV-infected patients, the rate of seroconversion after the first dose of an adjuvanted H1N1 influenza A vaccine was 68% and increased to 92% after a second doses.

Low rate of seroconversion after vaccination with a split virion, adjuvanted pandemic H1N1 influenza vaccine in HIV-1-infected patients.

Objective:To determine rates of seroconversion after single vaccination with a novel split virion, inactivated, adjuvanted pandemic H1N1 influenza vaccine (A/California/7/2009) in HIV-1-infected patients (ClinicalTrials.gov Identifier: NCT01017172). Design:Single center diagnostic study. Setting:Institutional HIV outpatient department of an urban university clinic. Participants:Adult HIV-1-infected individuals. Intervention:Serum samples were taken before and 21 days after vaccination. Main outcome measures:Antibody titers determined by hemagglutination inhibition assay. Seroconversion to vaccination was defined by either an antibody titer of 1: 10 or less before and of at least 1: 40 after or at least 1: 10 before and at least four-fold increase in antibody titer 21 days after single vaccination. Results:One hundred and sixty patients (125 men/35 women) were analyzed. Before vaccination, 23 patients (14.4%) had a hemagglutination inhibition assay titer of at least 1: 40. A median of 22 ± 3 days after vaccination, 110 (69%) patients seroconverted. Seroconverters were younger (45.1 ± 10.0 vs. 48.8 ± 11.3 years; P = 0.04), had a higher CD4 cell count (532 ± 227 vs. 475 ± 281 cells/μl; P = 0.03) and were more likely to have received a previous H5N1 vaccination in 2009 (25 vs. 8%; P = 0.02) when compared to nonresponders. No other significant differences were found comparing the two groups (prevaccination hemagglutination inhibition assay titer of ≥1: 40, AIDS, HAART, HIV RNA PCR <50 copies/ml or CD4 nadir, CD4 and CD8 percentage, sex, BMI, chronic hepatitis B or C). Conclusion:Seroconversion after one dose of a split virion, inactivated, adjuvanted pandemic H1N1 influenza vaccine of HIV-infected patients was 69%. Studies to investigate whether a second dose of the vaccine will increase seroconversion rate are needed.

The effect of injecting drug use history on disease progression and death among HIV-positive individuals initiating combination antiretroviral therapy: collaborative cohort analysis

We examined whether determinants of disease progression and causes of death differ between injecting drug users (IDUs) and non‐IDUs who initiate combination antiretroviral therapy (cART).

End‐stage renal disease and dialysis in HIV‐positive patients: observations from a long‐term cohort study with a follow‐up of 22 years

Renal disease is a common and serious complication in HIV‐infected patients.

Acute kidney injury caused by tenofovir disoproxil fumarate and diclofenac co-administration

The renal elimination of tenofovir (TFV) may be subject to renal drug−drug interactions that may increase the risk of kidney injury. Case reports indicated that diclofenac might increase TFV‐associated nephrotoxicity via a drug−drug interaction, leading to an increased intracellular TFV concentration in proximal tubular cells.

Quadruple Nucleos(t)ide Reverse Transcriptase Inhibitors-Only Regimen of Tenofovir Plus Zidovudine/Lamivudine/Abacavir in Heavily Pre-Treated HIV-1 Infected Patients: Salvage Therapy or Backbone Only?

BACKGROUND We investigated the virologic and immunologic responses to a mono-class, nucleoside/nucleotide reverse transcriptase inhibitor - combination therapy consisting of tenofovir and zidovudine/lamivudine/abacavir in therapy experienced patients. METHODS Retrospective study of 122 patients. Primary analysis was performed at 48 weeks. Virologic response was defined as viral load levels less than 400 copies/ml. RESULTS About half of the patients had switched to tenofovir+ zidovudine/lamivudine/abacavir for simplification purposes or toxicity while the other half had experienced virologic failure. 80/122 (66%) responded. Median viral load decreased to 78 copies/ml at week 48; median CD4 count increased to 321 cells/mm(3). Of the 42 virologic failures, only 3 patients failed after week 24. 24/35 patients who had been on a non-suppressive zidovudine/lamivudine/abacavir-only regimen at baseline and added tenofovir to intensify, responded. 41/53 patients who switched from any nucleoside reverse transcriptase inhibitor-only regimen improved or maintained suppression. Genotypes were available for 85/122 patients. The only predictor of virologic failure was the combination 41L+210W+215Y/F mutational pattern. 16 of the patients who failed on tenofovir+ zidovudine/lamivudine/abacavir therapy selected new primary nucleoside reverse transcriptase inhibitor resistance mutations that they previously did not have. 48/85 (56%) patients with genotype tests had at least 3 (3-10; median 4) nucleoside reverse transcriptase inhibitor resistance-associated mutations in the past. CONCLUSIONS Patients heavily pre-treated with nucleoside analogues may show response to mono-class tenofovir+ zidovudine/lamivudine/abacavir therapy despite having a history of failure with nucleoside reverse transcriptase inhibitors. Lower baseline viral load, higher baseline CD4 count were significant predictors for response. Archived 41L+210W+215Y/F mutational pattern was significantly associated with non-response.

Efficacy of raltegravir-containing regimens in antiretroviral-naïve and -experienced individuals in routine clinical practice

Summary Raltegravir is one of the standard antiretroviral therapy (ART) options in treatment-experienced and -naïve patients. However, efficacy data from clinical practice are scarce. Therefore, the efficacy of raltegravir-containing ART in clinical practice was investigated retrospectively. In all, 295 treatment-naïve and -experienced patients were analysed using two different cut-offs for virological failure (200 or 50 copies/ml). The response at week 24 and onwards was evaluated as a ‘time to loss of virological response’ analysis and estimated as a survival function. Additionally, dual therapy regimens (raltegravir plus boosted protease inhibitor) were compared to standard combinations in experienced patients performing a snapshot analysis at weeks 24 and 48, as well as a time to loss of virological response analysis. A total of 86.2% of the 64 treatment-naïve patients maintained virological suppression using a cut-off of 200 copies/ml (c/ml), while 67.7% maintained virological suppression with a 50 copies/ml cut-off from week 24 until the end of observation. Among the 231 treatment-experienced patients, 84.8% maintained virological suppression from week 24 onwards using a cut-off of 200 copies/ml; and 71.0% using 50 copies/ml, respectively. In the subgroup snapshot analysis at week 24, 98.3% (86.7% using a cut-off of 50 copies/ml) and at week 48, 93.3% (80.0%) of patients responded to dual therapy. Patients who were receiving a standard background therapy responded in 88.3% (81.3%) at week 24 and in 86.0% (80.7%) at week 48. Differences were not significant. This study shows again the overall long-term efficacy of raltegravir-based ART and furthermore gives reference for a comparable efficacy of dual and standard nucleos(t)ide reverse transcriptase inhibitor–backbone regimens in experienced patients on raltegravir over a period of 48 weeks in a real-life cohort where patients with severe comorbidities were included.

Evolution and function of the HCV NS3 protease in patients with acute hepatitis C and HIV coinfection

Little is known about the importance of the hepatitis C virus (HCV) NS3 protease in acute hepatitis C. In this prospective study, 82 consecutive patients with acute hepatitis C and human immunodeficiency virus (HIV) coinfection were enrolled. Individuals were infected with highly related HCV strains and the baseline NS3 quasispecies diversity and complexity was higher compared to a chronic hepatitis C control group (P<0.0001). Both parameters were comparable in patients with spontaneous clearance (n=6) versus treatment-induced SVR (n=5) or development of chronic hepatitis C (n=9). Longitudinal NS3 quasispecies kinetics showed a trend to a decreasing diversity and complexity (P<0.05) within 4 weeks in patients with spontaneous clearance compared to the other groups. The innate immune signalling protein CARDIF was cleaved to a similar extent independent of the outcome. Together with a more pronounced viral load decline (P<0.05), an early decreasing NS3 quasispecies evolution indicates spontaneous clearance of acute hepatitis C.