Anna B. Pierce

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.

Non-occupational post-exposure prophylaxis in Victoria, Australia: responding to high rates of re-presentation and low rates of follow-up

In Australia, the non-occupational post-exposure prophylaxis service in Victoria (VNPEPS) maintains a database of non-occupational post-exposure prophylaxis (NPEP) use throughout the state. Through the database the service can monitor and respond to patterns of NPEP presentation, re-presentation and follow-up as well as those who test positive for HIV. We describe a cohort of NPEP individuals from the commencement of the service to 31 December 2009. During this time, 1864 individuals presented for NPEP on 2396 occasions. The majority (85%) were men who have sex with men (MSM) presenting after receptive anal intercourse (56.1%). Repeat NPEP presentations were high (17.5%) and follow-up testing at week 12 post-NPEP was low (34%). Twenty-two patients (1.2%) tested positive for HIV at baseline presentation and six patients seroconverted to HIV during follow-up. The VNPEPS has initiated strategies to encourage behaviour change for those who re-present for NPEP, and to improve rates of week 12 follow-up.

Is the recommendation for pneumococcal vaccination of HIV patients evidence based

BACKGROUND both the current NHMRC guidelines of Australia and the USPHS/IDSA guidelines recommend pneumococcal vaccine be given to all patients with HIV infection despite a paucity of data to support these recommendations. OBJECTIVES the aim of this study was to assess the incidence of invasive pneumococcal disease and use of pneumococcal vaccine in HIV-infected patients at The Alfred Hospital, Melbourne, Australia, and to review the evidence for the current recommendations. STUDY DESIGN a case record review of all HIV-infected patients followed at The Alfred Hospital diagnosed with pneumonia between 1 June 1996 and 1 June 2000 was performed. Main outcome measures were the incidence of invasive pneumococcal disease and the proportion of these individuals who received pneumococcal vaccination. RESULTS Invasive pneumococcal disease was a relatively infrequent event with an incidence of 1.9 per 1000 person years. This rate is lower than the 8.2 per 1000 person years reported for confirmed disease by CDC. Of the 34 patients with either definite invasive, presumptive or possible pneumococcal disease, 16 (47%) had received pneumococcal vaccine, seven of these within 5 years prior to the episode of pneumonia. In 15 cases, the vaccine was administered when the CD4 cell count was <500 per microl. CONCLUSION lack of efficacy data, rarity of invasive disease plus evidence of infrequent administration delivered predominantly to those who are least likely to benefit, has prompted us to question the value of routinely vaccinating all our HIV-infected patients with pneumococcal vaccine. Review of the published literature provides conflicting data in support of the current recommendations for administration of pneumococcal vaccine in HIV patients. It may be more cost-effective to concentrate efforts on strategies to improve adherence to ARV therapy, as this has unequivocally been shown to be associated with a reduction in the incidence of pneumococcal disease.

HIV seroconversions among male non-occupational post-exposure prophylaxis service users: a data linkage study.

BACKGROUND Despite widespread prescription of non-occupational post-exposure prophylaxis (NPEP) in Victoria, little is known about subsequent HIV acquisition among NPEP users. We linked the Victorian NPEP Service (VNPEPS) database and the Victorian HIV Surveillance Registry to determine the number, incidence rate and predictive factors of HIV seroconversions among users of the VNPEPS. METHODS Records from male patients that received NPEP in the VNPEPS database (n = 1420) between January 2001 and February 2008 were linked with all entries in the Victorian HIV Surveillance Registry up to May 2008. RESULTS Sixty-one men who presented to the VNPEPS were identified as HIV seropositive; 16 of these were diagnosed at initial presentation for NPEP. The incidence of HIV seroconversion in males who were HIV seronegative at first presentation for NPEP was 1.27 (95% confidence interval 0.95-1.70) per 100 person-years. There was no association between HIV seroconversion and number of NPEP presentations or age. The median age of seroconversion was 34.6 years. CONCLUSION The incidence of HIV infection among men presenting to the VNPEPS is slightly lower than the HIV incidence in NPEP users in a recent Australian cohort study of men who have sex with men, but higher than HIV incidence in general gay male populations. Frequency of NPEP use was not associated with risk of HIV seroconversion. Examination of risk behaviour before and after NPEP use in this population is required to further assess the impact of NPEP availability and use on HIV incidence rates and risk behaviour in Australia.

Single-Tablet Emtricitabine-Rilpivirine-Tenofovir as HIV Postexposure Prophylaxis in Men Who Have Sex With Men

BACKGROUND Completion rates for human immunodeficiency virus (HIV) postexposure prophylaxis (PEP) are low. We investigated the adherence and safety of coformulated emtricitabine (FTC), rilpivirine (RPV), and tenofovir disoproxil fumarate (TDF) as a 3-drug, single-tablet regimen for PEP in men who have sex with men (MSM). METHODS In an open-label, single-arm study at 2 public sexual health clinics and 2 hospital emergency departments in urban Australia, 100 HIV-uninfected MSM requiring 3-drug PEP received single-tablet FTC-RPV-TDF once daily for 28 days. The primary endpoint was premature PEP cessation or primary HIV infection through week 12. Additional endpoints were adherence (by self-report of doses missed or not ingested with a meal, by pill count, and by plasma concentrations of tenofovir and FTC at week 4); and safety (clinical and laboratory adverse events [AEs]). RESULTS PEP completion was 92% (95% confidence interval, 85%-96%); premature cessation resulted from loss to follow-up (6%), AEs (1%), or study burden (1%). No participant was found to acquire HIV through week 12. Adherence was 98.6% (standard deviation [SD], 2.4) by pill count and 98.5% (SD, 2.7) by self-report; 86% reported taking all doses with food, and 88% of the subset tested had plasma tenofovir levels suggesting full adherence (>40 ng/mL). Eighty-eight participants experienced at least 1 clinical AE; 4 had grade 3 AEs or higher, possibly attributable to study drug. Fifty-six participants experienced at least 1 laboratory AE; 4 had AEs of grade 3 or higher, possibly attributable to study drug. CONCLUSIONS A single-tablet regimen of FTC-RPV-TDF was well tolerated as once-daily PEP, with high levels of adherence and completion. CLINICAL TRIALS REGISTRATION NCT01715636.

Adherence to HIV treatment guidelines for comorbid disease assessment and initiation of antiretroviral therapy.

Background:There are limited data on adherence to HIV treatment guidelines. We assessed adherence to US Department of Health and Human Services guidelines with Australian Commentary for adults initiating antiretroviral therapy (ART). Methods:Data were recorded regarding “when to start”, “what to start” and pre-ART comorbid disease assessment for consecutive adults initiating ART at primary care and hospital clinics in Sydney and Melbourne from 2004 through 2008. Independent predictors of adherence to guidelines were calculated by stepwise logistic regression. Results:For the 500 subjects (95.9% male, mean 40.2 years, median CD4 count 270 cells/&mgr;L) “when to start” adherence was 87.6%, and was less likely with initiation in a clinical trial [0.25 (95% CI: 0.13 to 0.49); P < 0.0001] and previous, short-term nontherapeutic antiretroviral exposure [0.08 (0.03 to 0.25); P < 0.0001]. “What to start” adherence was 69.0% for guideline-“preferred” regimens (85.8% for guideline-“preferred” or “alternative” regimens) and more likely with ART initiated in 2008 versus pre-2008 [OR: 2.69 (1.64 to 4.61); P = 0.0001]. Median comorbid disease assessment adherence was 56.8%, ranging from 25.6% for urinalysis to 99.2% for white blood cell count, and was more likely in patients with AIDS, and initiating ART in hospital or in a clinical trial. Hospital clinics were more likely to perform antiretroviral resistance testing (71.2% vs. 46.4%, P < 0.0001), to use “preferred” ART regimens (76.8% vs. 62.2%, P = 0.0002) but less likely to promote healthy diet and lifestyle (63.4% vs. 36.4%, P < 0.0001). Conclusions:“When to start” and “what to start” guidelines have been largely adhered to in Australia, but pre-ART comorbid disease assessment requires greater attention.

Protocol for an HIV pre-exposure prophylaxis (PrEP) population level intervention study in Victoria Australia: the PrEPX study

Background: Pre-exposure prophylaxis (PrEP) is the use of HIV anti-retroviral therapy to prevent HIV transmission in people at high risk of HIV acquisition. PrEP is highly efficacious when taken either daily, or in an on-demand schedule. In Australia co-formulated tenofovir-emtricitabine is registered for daily use for PrEP, however, this co-formulation is not listed yet on the national subsidized medicines list. We describe a study protocol that aims to demonstrate if the provision of PrEP to up to 3800 individuals at risk of HIV in Victoria, Australia reduces HIV incidence locally by 25% generally and 30% among GBM. Methods: PrEPX is a population level intervention study in Victoria, Australia in which generic PrEP will be delivered to 3800 individuals for up to 36 months. Study eligibility is consistent with the recently updated 2017 Australian PrEP guidelines. Participants will attend study clinics, shared care clinics, or outreach clinics for quarterly HIV/STI screening, biannual renal function tests and other clinical care as required. Study visits and STI diagnoses will be recorded electronically through the ACCESS surveillance system. At each study visit participants will be invited to complete behavioral surveys that collect demographics and sexual risk data. Diagnosis and behavioral data will be compared between PrEPX participants and other individuals testing within the ACCESS surveillance system. A subset of participants will complete in depth surveys and interviews to collect attitudes, beliefs and acceptability data. Participating clinics will provide clinic level data on implementation and management of PrEPX participants. The population level impact on HIV incidence will be assessed using Victorian HIV notification data. Discussion: This study will collect evidence on the real world impact of delivery of PrEP to 3800 individuals at risk of acquiring HIV in Victoria. This study will provide important information for the broader implementation of PrEP planning upon listing of the tenofovir-emtricitabine on the national subsidized list of medicines. The study is registered on the Australian New Zealand Clinical Trials Registry (ACTRN12616001215415)

Comparing non-occupational post-exposure prophylaxis drug regimens for HIV: Insights from a linked HIV surveillance system

Background International non-occupational post-exposure prophylaxis (NPEP) guidelines recommend routine use of three drug NPEP regimens, despite absence of evidence for greater prevention efficacy compared with two drug regimens. This study examines the potential for excess HIV seroconversions among high-risk men who have sex with men (MSM) reporting receptive anal intercourse with a source of unknown HIV serostatus (RAIU) following a two-drug versus a three-drug NPEP regimen. METHODS Data for MSM in the Victorian NPEP service database between 10 August 2005 and 31 December 2012 were linked with all Victorian HIV notifications up to 31 December 2013. The primary outcome was NPEP failure following NPEP presentation among MSM reporting RAIU, stratified by the number of drugs prescribed. RESULTS Among 1482 MSM reporting 2002 episodes of RAIU and prescribed two- or three-drug NPEP, 70 seroconverted to HIV, but only 19 were considered possible NPEP failures. HIV diagnosis incidence among men reporting RAIU was 1.2/100 person years (PY) (95%CI=1.0-1.6); 1.1/100 PY (95%CI=0.8-1.4) among MSM prescribed two drugs and 2.2/100 PY (95%CI=1.4-3.7) among MSM prescribed three drugs (P<0.01). Of the 19 possible NPEP failures, 13 (0.7%) were prescribed two drugs and six (2.7%) three drugs (P<0.001). CONCLUSIONS This study suggests that two-drug NPEP regimens do not result in excess seroconversions compared with three-drug regimens when used following RAIU. Clinical services should carefully consider their use of three drug NPEP and whether resources might be better invested in other prevention strategies, particularly pre-exposure prophylaxis (PrEP).

Developing an evidence-based guideline for the management of exposure to hepatitis B at a Victorian tertiary hospital

Objective: To develop a guideline for the management of potential exposures to hepatitis B virus (HBV) at The Alfred Hospital, based on results of clinical audit, database analysis and literature review.

Dolutegravir with tenofovir disoproxil fumarate-emtricitabine as HIV postexposure prophylaxis in gay and bisexual men.

Objectives: Completion rates for HIV postexposure prophylaxis (PEP) are often low. We investigated the adherence and safety of dolutegravir (DTG; 50 mg daily) with tenofovir disoproxil fumarate–emtricitabine (TDF–FTC; 300/200 mg, respectively) as three-drug PEP in gay and bisexual men. Design: Open-label, single-arm study at three sexual health clinics and two emergency departments in Australia. Methods: In total, 100 HIV-uninfected gay and bisexual men requiring PEP received DTG and TDF–FTC for 28 days. The primary end point was PEP failure (premature PEP cessation or primary HIV infection through week 12). Additional end points were adherence by self-report (n = 98) and pill count (n = 55), safety, and plasma drug levels at day 28. Results: PEP completion was 90% (95% confidence interval 84–96%). Failures (occurring at a median 9 days, interquartile range 3–16) comprised loss to follow-up (9%) and adverse event resulting in study drug discontinuation (headache, 1%). No participant was found to acquire HIV through week 12. Adherence to PEP was 98% by self-report and in the 55 participants with corresponding pill count data. The most common clinical adverse events were fatigue (26%), nausea (25%), diarrhoea (21%), and headache (10%). There were only four grade 3–4 subjective adverse events. The most common laboratory adverse event was raised alanine aminotransferase (22%), but there was no case of clinical hepatitis. At day 28, the mean estimated glomerular filtration rate decrease was 14 ml/min/1.73m2 (SD 17, P = 0.001); an estimated glomerular filtration rate of less than 60 ml/min/1.73m2 occurred in 3%. Conclusions: DTG with TDF–FTC is a well tolerated option for once-daily PEP.