Design and implementation of a randomized crossover study of valproic acid and antiretroviral therapy to reduce the HIV reservoir.

BACKGROUND: HIV reservoirs represent the major obstacles for eradication and are defined as a cell type that allows persistence of replication-competent HIV in patients on optimal long-term antiretroviral therapy (HAART). Several pilot clinical trials have been implemented to assess the value of experimental therapy to reduce reservoir size or eradicate HIV. In order to eradicate HIV, valproic acid was used as a new strategy to increase viral gene expression in the nucleus of infected cells with the expectation of generating a direct cell death or destruction by nearby cytotoxic cells. Previous pilot studies using VPA have showed conflicting results on the ability of VPA to reduce the size of HIV reservoirs. PURPOSE: As the role of VPA on HIV reservoirs remains unclear, we conducted a multicenter clinical trial with a specific study design to obtain optimal information on reservoir changes while exposing the smallest number of individuals to the experimental medication. METHOD: To this aim, a randomized, crossover design with 2 different treatment durations was implemented. By doubling the therapeutic period in one study arm, we were in a position to assess the impact of an extended duration of VPA on the size of the HIV reservoir and to evaluate the duration of treatment effects upon VPA withdrawal in the other arm. However, limitations for this type of study design included the logistical complexity of 2 uneven study arms and longer study duration. CONCLUSION: Despite the absence of demonstrable impact of VPA on reservoir size, such crossover study design should be considered in the early stage testing of novel HIV therapeutics targeted to reduce reservoir size or eradicate HIV.

Valproic acid in association with highly active antiretroviral therapy for reducing systemic HIV-1 reservoirs: results from a multicentre randomized clinical study.

OBJECTIVES: Conflicting results have been reported regarding the ability of valproic acid (VPA) to reduce the size of HIV reservoirs in patients receiving suppressive highly active antiretroviral therapy (HAART). In a randomized multicentre, cross-over study, we assessed whether adding VPA to stable HAART could potentially reduce the size of the latent viral reservoir in CD4 T cells of chronically infected patients. METHODS: A total of 56 virologically suppressed patients were randomly assigned either to receive VPA plus HAART for 16 weeks followed by HAART alone for 32 weeks (arm 1; n = 27) or to receive HAART alone for 16 weeks and then VPA plus HAART for 32 weeks (arm 2; n = 29). VPA was administered at a dose of 500 mg twice a day (bid) and was adjusted to the therapeutic range. A quantitative culture assay was used to assess HIV reservoirs in CD4 T cells at baseline and at weeks 16 and 48. RESULTS: No significant reductions in the frequency of CD4 T cells harbouring replication-competent HIV after 16 and 32 weeks of VPA therapy were observed. In arm 1, median (range) values of IU per log(10) billion (IUPB) cells were 2.55 (range 1.20-4.20), 1.80 (range 1.0-4.70) and 2.70 (range 1.0-3.90; P = 0.87) for baseline, week 16 and week 48, respectively. In arm 2, median values of IUPB were 2.55 (range 1.20-4.65), 1.64 (range 1.0-3.94) and 2.51 (range 1.0-4.48; P = 0.50) for baseline, week 16 and week 48, respectively. CONCLUSIONS: Our study demonstrates that adding VPA to stable HAART does not reduce the latent HIV reservoir in virally suppressed patients.

Treatment durability, effectiveness, and safety with atazanavir/ritonavir-based HAART regimen in treatment-naïve HIV-infected patients.

PURPOSE: To describe the durability of treatment, virological and immunological response, and safety of an atazanavir/ritonavir (ATV/RTV)-based highly active antiretroviral therapy (HAART) regimen in treatment-naïve HIV-infected patients. METHODS: This was a multicentre retrospective study. Medical charts of antiretroviral-na'i've HIV-infected adults who initiated ATV/RTV (300/100 mg) from January 2004 to December 2007 in 10 Canadian clinics were reviewed. Data were collected from time of ATV/RTV treatment initiation until discontinuation of ATV. Durability of treatment and time to virological response were estimated with Kaplan-Meier functions. Change in viral load, CD4 cell counts, and lipid parameters were assessed with linear regression analyses. RESULTS: 176 patients were enrolled, 153 (86.9%) were male, and the majority (52.3%) were 40 to 54 years old. Duration of observation ranged from 1.6 to 56 months. The mean (SE) durability of treatment was 33.5 (0.7) months. There were 37 (21.0%) patients who discontinued ATV/ RTV, among whom 18 (10.2%) discontinued due to toxicity, suboptimal virological response, loss to follow-up, or death. The mean (SE) time to HIV viral load of <50 and <400 copies/mL was 6.6 (0.4) and 4.3 (0.3) months, respectively. At 96 weeks of treatment, least squares mean (LSM) estimated change in log10(HIV copies/mL) was -2.94 (P < .001) and +245 cells/mL (P < .001) for CD4 cell count. A significant LSM increase in HDL-C of 0.24 mmol/L (P = .007 for trend over time) was also observed; total cholesterol, triglycerides, and LDL-C increased over time but their change did not reach statistical significance. The most frequently reported adverse event was increased bilirubin (16.5%). CONCLUSIONS: ATV/RTV-based first-line HAART regimen demonstrated durability and effectiveness and was well tolerated in treatment-naïve HIV-infected patients.

Effect of antiretroviral therapy on HIV-1 genetic evolution during acute infection.

The rapid evolution of HIV-1 is a major obstacle to viral eradication. Early antiretroviral therapy (ART) during primary HIV-1 infection could limit viral diversity. Eighteen patients recently infected with HIV-1 were selected. Nine initiated ART soon after enrolment and nine remained untreated. Replication-competent (RC) viruses were quantified at baseline and after one year of follow-up. Viral diversity in the C2V5 envelope region was evaluated from plasma, peripheral blood mononuclear cells (PBMCs), and cell culture at both time points. The amount of RC virus in the treated group declined (median -5.42 infectious units per million [IUPM]) while it remained stable or increased in the untreated group (median +0.87 IUPM). At one year post infection, we observed a significant increase in diversity for the C2V5 (+0.150%) region, specifically in the hypervariable loops V4 (+0.73%) and V5 (+0.77%), in the untreated group. More importantly, viral diversity did not significantly increase in treated individuals during the first year post infection. Genetic diversity during primary infection remains low through the first year of infection. Early treatment could contribute to a decrease in RC viruses from PBMCs and to limitation of viral diversification in the viral reservoir. These findings may have relevance for the rational design of specific immunotherapeutic strategies.

Long-term efficacy and safety of fosamprenavir plus ritonavir versus lopinavir/ritonavir in combination with abacavir/lamivudine over 144 weeks.

PURPOSE: The KLEAN study extension assessed the long-term efficacy and safety of fosamprenavir-ritonavir (FPV/r) and lopinavir-ritonavir (LPV/r), both administered with abacavir/lamivudine (ABC/3TC) fixed dose combination, over 144 weeks. METHODS: KLEAN was an open-label, noninferiority study that randomised antiretroviral-naïve patients to FPV/r twice daily (bid) or LPV/r bid with ABC/3TC once daily (qd). Patients with a viral load of <400 copies/mL at Week 48 were eligible to participate in the KLEAN study extension (up to 144 weeks) and continued with their previously randomised therapy. RESULTS: The KLEAN study extension (48 to 144 weeks) randomized 199 patients. The proportion of TLOVR responders (HIV-1 RNA <50 copies/mL) at Week 144 was 73% and 60% in the FPV/r and LPV/r arms, respectively. The proportion of TLOVR responders (<50 copies/mL) was the same irrespective of baseline HIV-1 RNA (>100,000 or 100,000 copies/mL). The Week 144 median (interquartile range) change from baseline CD4+ cell count was 300 (236-433) cells/mm3 and 335 (225-444) cells/mm3 in the FPV/r and LPV/r arms, respectively. Diarrhea was the most frequently reported adverse event. A small proportion of patients (FPV/r, 13%; LPV/r, 9%) discontinued study medication due to adverse events. Three patients (FPV/r, 1; LPV/r, 2) experienced virological failure between Week 48 and Week 144. CONCLUSION: The findings of the KLEAN study extension (48 to 144 weeks) support durable viral suppression with both FPV/r and LPV/r treatment regimens when used in combination with ABC/3TC irrespective of viral load at baseline. Both regimens were well tolerated and had similar safety profiles.

Longitudinal assessment of changes in HIV-specific effector activity in HIV-infected patients starting highly active antiretroviral therapy in primary infection.

Both the magnitude and breadth of HIV-specific immunity were evaluated longitudinally on samples collected from six subjects starting highly active antiretroviral therapy (HAART) preseroconversion (group 1), 11 recently infected subjects starting HAART postseroconversion (group 2), five subjects starting HAART in the second half of the first year of infection (group 3), and six persons starting treatment in the chronic phase of infection (group 4). HIV-specific immunity was measured by IFN-gamma ELISPOT, detecting the frequency of cells responding to a panel of HLA-restricted HIV-1 peptides. Intracellular cytokine staining was used to detect the frequency of HIV-1 Gag p55-specific CD4(+) and CD8(+) T cells in a subset of participants. The magnitude and breadth of HIV-specific responses persisted in all group 1 subjects and in 5 of 11 (45%) group 2 subjects. Both of these parameters declined in 6 of 11 (55%) group 2 and in all group 3 and 4 individuals. All persons who maintained detectable numbers of HIV-1 Gag p55-specific CD4(+) and CD8(+) T cells after starting HAART preserved the intensity and breadth of their HIV-specific effector response. Our results show that HIV-specific immunity can be preserved even if HAART is initiated beyond the acute phase of infection.

Predictors of chlamydial infection and gonorrhea among patients seen by private practitioners.

OBJECTIVE: To identify the predictors of chlamydial infection and gonorrhea among patients tested by general practitioners. DESIGN: Prospective study. SETTING: General private practice, family planning and abortion clinic, adolescent clinic, sexually transmitted disease (STD) clinic and community health clinic in downtown Montreal. PATIENTS: The 2856 patients were included because of symptoms compatible with an STD, a history of sexual contact with a person known or suspected to have chlamydial infection, a history of a nonexclusive sexual relationship or presentation for an abortion. MEASURES: Patient information was obtained by the attending physician on a standard form. Enzyme immunoassay (EIA) for Chlamydia trachomatis and culture for Neisseria gonorrhoeae were performed on cervical (female) or urethral (male) samples. Stepwise logistic regression was used to identify the predictors of infection. RESULTS: The EIA results were positive in 11.1% of the cases and the culture results in 2.3%. Among the males chlamydial infection was independently associated with low age (odds ratio [OR] = 0.88 per year), heterosexuality (OR = 4.99), urethral discharge (OR = 3.74) and the absence of a history of gonorrhea (OR = 0.51). Gonorrhea was associated with urethral discharge (OR = 24.3) and homosexuality (OR = 3.68). Among the females chlamydial infection was associated with low age (OR = 0.79 per year), a history of sexual contact with a person known to have chlamydial infection (OR = 2.30), multiple sexual partners in the previous 12 months (OR = 1.60) and a reason for the test other than screening purposes (OR = 0.60). Gonorrhea was associated with a reason other than screening (OR = 0.24) and low age (OR = 0.74 per year). Among the patients tested for screening purposes age was the only significant predictor of chlamydial infection (OR = 0.79 per year), and the prevalence of gonorrhea was 0.4%. The actual rate of chlamydial infection was 11.8% among the patients younger than 25 years, 5.7% among those 25 to 34 years and 0.6% among those over 34. CONCLUSIONS: Age alone can be used as a criterion to screen for chlamydial infection among asymptomatic patients without a history of sexual contact with a person known or suspected to have such infection and with a history of a nonexclusive relationship. The prevalence in our population justifies screening people up to 34 years of age.