Tim Spelman

Activation of HIV Transcription with Short-Course Vorinostat in HIV-Infected Patients on Suppressive Antiretroviral Therapy

Human immunodeficiency virus (HIV) persistence in latently infected resting memory CD4+ T-cells is the major barrier to HIV cure. Cellular histone deacetylases (HDACs) are important in maintaining HIV latency and histone deacetylase inhibitors (HDACi) may reverse latency by activating HIV transcription from latently infected CD4+ T-cells. We performed a single arm, open label, proof-of-concept study in which vorinostat, a pan-HDACi, was administered 400 mg orally once daily for 14 days to 20 HIV-infected individuals on suppressive antiretroviral therapy (ART). The primary endpoint was change in cell associated unspliced (CA-US) HIV RNA in total CD4+ T-cells from blood at day 14. The study is registered at ClinicalTrials.gov (NCT01365065). Vorinostat was safe and well tolerated and there were no dose modifications or study drug discontinuations. CA-US HIV RNA in blood increased significantly in 18/20 patients (90%) with a median fold change from baseline to peak value of 7.4 (IQR 3.4, 9.1). CA-US RNA was significantly elevated 8 hours post drug and remained elevated 70 days after last dose. Significant early changes in expression of genes associated with chromatin remodeling and activation of HIV transcription correlated with the magnitude of increased CA-US HIV RNA. There were no statistically significant changes in plasma HIV RNA, concentration of HIV DNA, integrated DNA, inducible virus in CD4+ T-cells or markers of T-cell activation. Vorinostat induced a significant and sustained increase in HIV transcription from latency in the majority of HIV-infected patients. However, additional interventions will be needed to efficiently induce virus production and ultimately eliminate latently infected cells. Trial Registration ClinicalTrials.gov NCT01365065

Galactomannan and PCR versus culture and histology for directing use of antifungal treatment for invasive aspergillosis in high-risk haematology patients: a randomised controlled trial

BACKGROUND Empirical treatment with antifungal drugs is often used in haematology patients at high risk of invasive aspergillosis. We compared a standard diagnostic strategy (culture and histology) with a rapid biomarker-based diagnostic strategy (aspergillus galactomannan and PCR) for directing the use of antifungal treatment in this group of patients. METHODS In this open-label, parallel-group, randomised controlled trial, eligible patients were adults undergoing allogeneic stem-cell transplantation or chemotherapy for acute leukaemia, with no history of invasive fungal disease. Enrolled patients were randomly assigned (1:1) by a computer-generated schedule to follow either a standard diagnostic strategy (based on culture and histology) or a biomarker-based diagnostic strategy (aspergillus galactomannan and PCR) to direct treatment with antifungal drugs. Patients, were followed up for 26 weeks or until death. Masking of the use of different diagnostic tests was not possible for patients, treating physicians, or investigators. The primary endpoint was empirical treatment with antifungal drugs in the 26 weeks after enrolment (for the biomarker-based diagnostic strategy, a single postive galactomannan or PCR result was deemed insufficient to confirm invasive aspergillosis, so treatment in this context was classified as empirical). This outcome was assessed by an independent data review committee from which the study allocations were masked. Analyses were by intention to treat and included all enrolled patients. This study is registered with ClinicalTrial.gov, number NCT00163722. FINDINGS 240 eligible patients were recruited from six Australian centres between Sept 30, 2005, and Nov 19, 2009. 122 were assigned the standard diagnostic strategy and 118 the biomarker-based diagnostic strategy. 39 patients (32%) in the standard diagnosis group and 18 (15%) in the biomarker diagnosis group received empirical antifungal treatment (difference 17%, 95% CI 4-26; p=0·002). The numbers of patients who had hepatotoxic and nephrotoxic effects did not differ significantly between the standard diagnosis and biomarker diagnosis groups (hepatotoxic effects: 21 [17%] vs 12 [10%], p=0·11; nephrotoxic effects: 52 [43%] vs 60 [51%], p=0·20). INTERPRETATION Use of aspergillus galactomannan and PCR to direct treatment reduced use of empirical antifungal treatment. This approach is an effective strategy for the management of invasive aspergillosis in high-risk haematology patients. FUNDING Australian National Health and Medical Research Council, Cancer Council New South Wales, Pfizer, Merck, Gilead Sciences.

High incidence of hepatitis C virus reinfection in a cohort of injecting drug users

An estimated 170 million people worldwide carry the hepatitis C virus (HCV), and in more developed countries the prevalence and incidence of HCV is particularly high among injecting drug users (IDUs). Spontaneous clearance of HCV infection and reinfection is well recognized but the level of protection against further infection conferred by HCV infection and clearance remains uncertain. We conducted a prospective study of HCV infection in IDUs recruited in Melbourne, Australia, using a much shorter median testing interval than in previous studies. Incidences of naive infection and reinfection were calculated by the person‐year method and Cox proportional hazards regression used to adjust for covariates. A significantly higher HCV incidence rate was measured in previously infected IDUs (46.8% per year) compared with HCV‐naive IDUs (15.5% per year). The hazard ratio for previously infected IDUs compared to HCV‐naive IDUs, after adjustment for time‐dependent covariates, was 2.54 (95% confidence interval, 1.11–5.78, P > |z| < 0.05). Viral persistence after reinfection appeared similar to that following naive infection. Conclusion: Our data suggest that HCV infection in IDUs is more likely following prior infection and clearance than in HCV‐naive individuals, implying no increased immunity against further infection. This result has important implications for the future development of an HCV vaccine. (HEPATOLOGY 2008;48:1746‐1752.)

Persistence on therapy and propensity matched outcome comparison of two subcutaneous interferon beta 1a dosages for multiple sclerosis

Objectives To compare treatment persistence between two dosages of interferon β-1a in a large observational multiple sclerosis registry and assess disease outcomes of first line MS treatment at these dosages using propensity scoring to adjust for baseline imbalance in disease characteristics. Methods Treatment discontinuations were evaluated in all patients within the MSBase registry who commenced interferon β-1a SC thrice weekly (n = 4678). Furthermore, we assessed 2-year clinical outcomes in 1220 patients treated with interferon β-1a in either dosage (22 µg or 44 µg) as their first disease modifying agent, matched on propensity score calculated from pre-treatment demographic and clinical variables. A subgroup analysis was performed on 456 matched patients who also had baseline MRI variables recorded. Results Overall, 4054 treatment discontinuations were recorded in 3059 patients. The patients receiving the lower interferon dosage were more likely to discontinue treatment than those with the higher dosage (25% vs. 20% annual probability of discontinuation, respectively). This was seen in discontinuations with reasons recorded as “lack of efficacy” (3.3% vs. 1.7%), “scheduled stop” (2.2% vs. 1.3%) or without the reason recorded (16.7% vs. 13.3% annual discontinuation rate, 22 µg vs. 44 µg dosage, respectively). Propensity score was determined by treating centre and disability (score without MRI parameters) or centre, sex and number of contrast-enhancing lesions (score including MRI parameters). No differences in clinical outcomes at two years (relapse rate, time relapse-free and disability) were observed between the matched patients treated with either of the interferon dosages. Conclusions Treatment discontinuations were more common in interferon β-1a 22 µg SC thrice weekly. However, 2-year clinical outcomes did not differ between patients receiving the different dosages, thus replicating in a registry dataset derived from “real-world” database the results of the pivotal randomised trial. Propensity score matching effectively minimised baseline covariate imbalance between two directly compared sub-populations from a large observational registry.

Switch to Natalizumab versus Fingolimod in Active Relapsing-Remitting Multiple Sclerosis

In patients suffering multiple sclerosis activity despite treatment with interferon β or glatiramer acetate, clinicians often switch therapy to either natalizumab or fingolimod. However, no studies have directly compared the outcomes of switching to either of these agents.

Biological determinants of immune reconstitution in HIV-infected patients receiving antiretroviral therapy: the role of interleukin 7 and interleukin 7 receptor α and microbial translocation.

BACKGROUND Multiple host factors may influence CD4(+) T cell reconstitution in human immunodeficiency virus (HIV)-infected patients after suppressive antiretroviral therapy (ART). We hypothesized that residual immune activation and polymorphisms in the interleukin 7 (IL-7) receptor α (IL-7Rα) gene were important for immune recovery. METHODS We examined HIV-infected patients receiving suppressive ART (n = 96) for their IL-7Rα haplotypes and measured levels of lipopolysaccharide (LPS), soluble CD14, and IL-7 in plasma samples collected before and after ART initiation. Levels of soluble IL-7Rα were measured in HIV-infected patients with IL-7Rα haplotype 2 (n = 11) and those without IL-7Rα haplotype 2 (n = 22). Multivariate analysis was used to identify variables associated with faster recovery to CD4(+) T cell counts of >500 and >200 cells/μL. RESULTS Both LPS and soluble CD14 levels were significantly decreased with ART (P < .001, respectively) but remained elevated compared with uninfected controls. In a multivariate analysis, faster recovery to a CD4(+) T cell count of >500 cells/μL was significantly associated with higher baseline CD4(+) T cell count, younger age, lower pre-ART LPS level, higher pre-ART soluble CD14 level, lower pre-ART IL-7 level, and IL-7Rα haplotype 2 (hazard ratio, 1.50; 95% confidence interval, 1.03-2.19; P = .034). HIV-infected patients with haplotype 2 had significantly lower soluble IL-7Rα levels compared with those of patients without haplotype 2 (P < .001). CONCLUSION Both the extent of immune depletion prior to ART and IL-7Rα haplotype 2 are important determinants of time to CD4(+) T cell recovery to counts of >500 cells/μL.

SPL7013 Gel (VivaGel®) retains potent HIV-1 and HSV-2 inhibitory activity following vaginal administration in humans.

SPL7013 Gel (VivaGel®) is a microbicide in development for prevention of HIV and HSV. This clinical study assessed retention and duration of antiviral activity following vaginal administration of 3% SPL7013 Gel in healthy women. Participants received 5 single doses of product with ≥5 days between doses. A cervicovaginal fluid (CVF) sample was collected using a SoftCup™ pre-dose, and immediately, or 1, 3, 12 or 24 h post-dose. HIV-1 and HSV-2 antiviral activities of CVF samples were determined in cell culture assays. Antiviral activity in the presence of seminal plasma was also tested. Mass and concentration of SPL7013 in CVF samples was determined. Safety was assessed by reporting of adverse events. Statistical analysis was performed using the Wilcoxon signed-rank test with Bonferroni adjustment; p≤0.003 was significant. Eleven participants completed the study. Inhibition of HIV-1 and HSV-2 by pre-dose CVF samples was negligible. CVF samples obtained immediately after dosing almost completely inhibited (median, interquartile range) HIV-1 [96% (95,97)] and HSV-2 [86% (85,94)], and activity was maintained in all women at 3 h (HIV-1 [96% (95,98), p = 0.9]; HSV-2 [94% (91,97), p = 0.005]). At 24 h, >90% of initial HIV-1 and HSV-2 inhibition was maintained in 6/11 women. SPL7013 was recovered in CVF samples obtained at baseline (46% of 105 mg dose). At 3 and 24 h, 22 mg and 4 mg SPL7013, respectively, were recovered. More than 70% inhibition of HIV-1 and HSV-2 was observed if there was >0.5 mg SPL7013 in CVF samples. High levels of antiviral activity were retained in the presence of seminal plasma. VivaGel was well tolerated with no signs or symptoms of vaginal, vulvar or cervical irritation reported. Potent antiviral activity was observed against HIV-1 and HSV-2 immediately following vaginal administration of VivaGel, with activity maintained for at least 3 h post-dose. The data provide evidence of antiviral activity in a clinical setting, and suggest VivaGel could be administered up to 3 h before coitus. Trial Registration The study is registered at ClinicalTrials.gov under identifier: NCT00740584

Determining the Impact of Text Messaging for Sexual Health Promotion to Young People

Background: The use of new technologies, such as mobile phones and internet, has increased dramatically in recent years. Text messages offer a novel method of sexual health promotion to young people who are the greatest users of new technology and are also at high risk of sexually transmitted infections (STIs). Methods: In January 2008, young people aged between 16 and 29 years were recruited from a music festival in Melbourne, Australia. They completed a short survey and were asked to provide their mobile phone numbers. Participants received fortnightly short messaging service (SMS) relating to sexual health for 4 months, and then completed an online follow-up survey. Survey data were weighted to account for those lost to follow-up. McNemars test was used to compare changes in survey responses. Results: A total of 1771 participants were included in analysis as they were sexually active and provided a valid mobile phone number at baseline. In all, 18% (319/1771) withdrew from receiving the SMS during the broadcast period and 40% (587/1452) completed the follow-up survey. The majority reported on the follow-up survey that they found the SMS entertaining (80%), informative (68%), and they showed the SMS to others (73%). Weighted analyses found a significant increase in knowledge (P < 0.01) and STI testing (P < 0.05) over time in both males and females. Conclusion: The findings indicate that SMS appear to be a feasible, popular, and effective method of sexual health promotion to young people with a relatively low withdrawal rate, positive feedback, and an observed improvement in sexual health knowledge and STI testing.

Comparative clinical effectiveness of prophylactic voriconazole/posaconazole to fluconazole/itraconazole in patients with acute myeloid leukemia/myelodysplastic syndrome undergoing cytotoxic chemotherapy over a 12-year period

Post-induction aplasia for acute myeloid leukemia/myelodysplastic syndrome is a high-risk period for invasive fungal diseases. The effectiveness of fluconazole, itraconazole solution, voriconazole and posaconazole prophylaxis used consecutively from December 1998 to January 2010 in patients with acute myeloid leukemia/myelodysplastic syndrome undergoing remission-induction chemotherapy was retrospectively evaluated. A total of 216 consecutive patients received 573 prophylaxis courses. Breakthrough-invasive fungal disease incidence in fluconazole, itraconazole, voriconazole, posaconazole recipients was 25%, 16%, 14% and 3%, respectively. Voriconazole/posconazole versus fluconazole/itraconazole combined was associated with significant reductions in breakthrough-invasive fungal disease incidence (20% vs. 8%, P=0.011), premature discontinuations (46% vs. 22% P<0.001) and empiric antifungal treatment (31% vs. 8.5%, P<0.001). Microbiologically confirmed infections were molds. Posaconazole compared to other drugs was associated with fewer courses requiring computed-tomography (43% vs. 26%, P<0.001). Adoption of voriconazole/posaconazole has decreased invasive fungal disease incidence, empiric antifungal treatment and for posaconazole, computed-tomography demand, with effectiveness of posaconazole comparable to clinical trial experience.

Inhibition of Telomerase Activity by Human Immunodeficiency Virus (HIV) Nucleos(t)ide Reverse Transcriptase Inhibitors: A Potential Factor Contributing to HIV-Associated Accelerated Aging

BACKGROUND Human immunodeficiency virus (HIV)-infected patients on combination active antiretroviral therapy (cART) are at increased risk of age-related complications. We hypothesized that nucleos(t)ide reverse transcriptase inhibitors (NRTI) may contribute to accelerated aging in HIV-infected individuals on cART via inhibition of telomerase activity. METHODS Telomerase activity and telomere length (TL) were measured by quantitative polymerase chain reaction in vitro in activated peripheral blood mononuclear cells (PBMCs) cultured with NRTI and ex vivo in PBMCs from uninfected patients exposed to NRTI and from HIV-infected patients on NRTI-containing cART. RESULTS Lamivudine, abacavir, zidovudine, emtricitabine, and tenofovir significantly inhibited telomerase activity in activated PBMCs in vitro. Tenofovir was the most potent inhibitor of telomerase activity and caused greatest shortening of TL in vitro at the therapeutic concentration of 0.3 μM. PBMCs from HIV-infected patients receiving NRTI-containing cART (n = 39) had significantly lower telomerase activity than HIV-uninfected patients (n = 47; P = .011) and HIV-infected patients receiving non-NRTI-containing cART (n = 11; P < .001). TL was significantly inversely associated with age (P = .009) and the total duration on any NRTI (P = .01). CONCLUSIONS NRTIs and, specifically tenofovir at therapeutic concentrations, inhibit telomerase activity leading to accelerated shortening of TL in activated PBMCs. The relationship between NRTI, reduced telomerase activity, and accelerated aging requires further investigation in HIV-infected individuals on cART.