Efficacy and safety of switching to dolutegravir/lamivudine in virologically suppressed people with HIV-1 aged ≥ 50 years: week 48 pooled results from the TANGO and SALSA studies.

BACKGROUND: As the population of people with HIV ages, concerns over managing age-related comorbidities, polypharmacy, immune recovery, and drug-drug interactions while maintaining viral suppression have arisen. We present pooled TANGO and SALSA efficacy and safety results dichotomized by age (< 50 and ≥ 50 years). METHODS: Week 48 data from the open-label phase 3 TANGO and SALSA trials evaluating switch to once-daily dolutegravir/lamivudine (DTG/3TC) fixed-dose combination vs continuing current antiretroviral regimen (CAR) were pooled. Proportions of participants with HIV-1 RNA ≥ 50 and < 50 copies/mL (Snapshot, intention-to-treat exposed) and safety were analyzed by age category. Adjusted mean change from baseline in CD4 + cell count was assessed using mixed-models repeated-measures analysis. RESULTS: Of 1234 participants, 80% of whom were male, 29% were aged ≥ 50 years. Among those aged ≥ 50 years, 1/177 (< 1%) DTG/3TC participant and 3/187 (2%) CAR participants had HIV-1 RNA ≥ 50 copies/mL at 48 weeks; proportions with HIV-1 RNA < 50 copies/mL were high in both treatment groups (≥ 92%), consistent with overall efficacy and similar to observations in participants aged < 50 years (≥ 93%). Regardless of age category, CD4 + cell count increased or was maintained from baseline with DTG/3TC. Change from baseline in CD4 + /CD8 + ratio was similar across age groups and between treatment groups. One CAR participant aged < 50 years had confirmed virologic withdrawal, but no resistance was detected. In the DTG/3TC group, incidence of adverse events (AEs) was similar across age groups. Proportions of AEs leading to withdrawal were low and comparable between age groups. Although drug-related AEs were generally low, across age groups, drug-related AEs were more frequent in participants who switched to DTG/3TC compared with those who continued CAR. While few serious AEs were observed in both treatment groups, more were reported in participants aged ≥ 50 years vs < 50 years. CONCLUSIONS: Among individuals with HIV-1, switching to DTG/3TC maintained high rates of virologic suppression and demonstrated a favorable safety profile, including in those aged ≥ 50 years despite higher prevalence of concomitant medication use and comorbidities. TRIAL REGISTRATION NUMBER: TANGO, NCT03446573 (February 27, 2018); SALSA, NCT04021290 (July 16, 2019).

Cardiometabolic Parameters 3 Years After Switch to Dolutegravir/Lamivudine vs Maintenance of Tenofovir Alafenamide-Based Regimens.

Background: Cardiometabolic outcomes were investigated 3 years after switching to the 2-drug regimen dolutegravir/lamivudine (DTG/3TC) vs continuing 3-/4-drug tenofovir alafenamide (TAF)-based regimens in a multicenter phase 3 noninferiority study based on an open-label randomized design. Method: Adults with virologically suppressed HIV-1 switched to once-daily DTG/3TC (n = 369) or continued TAF-based regimens (n = 372). Cardiometabolic health parameters were assessed through week 144 via mixed-model repeated measures or logistic regression analyses, adjusting for baseline variables. Results: At week 144, 13% (42/316) of the DTG/3TC group and 12% (37/303) of the TAF-based regimen group had ≥10% weight gain from baseline (adjusted odds ratio, 1.11; 95% CI, .68-1.80). Adjusted change from baseline in serum leptin, a surrogate marker of adiposity, was similar between groups (treatment ratio, 1.00; 95% CI, .89-1.13). The lipid profile generally favored DTG/3TC in the baseline boosted subgroup. Adjusted odds revealed no clinically meaningful differences between groups: homeostatic model assessment of insulin resistance ≥2 (adjusted odds ratio, 0.79; 95% CI, .50-1.26), metabolic syndrome (International Diabetes Federation criteria, 0.99; .59-1.68), hepatic fibrosis (fibrosis-4 index score ≥1.45, 1.39; .63-3.06), and coronary artery disease risk (Framingham risk score ≥10%, 0.92; .56-1.49). Baseline variables and characteristics associated with odds of each cardiometabolic parameter outcome were consistent with known risk factors, including age, sex, race, and some disease characteristics. Conclusions: Cardiometabolic health 3 years after switching to DTG/3TC was comparable to that for individuals continuing TAF-based regimens, further supporting DTG/3TC as a robust switch option with a stable metabolic profile. Trial registration: ClinicalTrials.gov NCT03446573.

Characteristics of Human Immunodeficiency Virus (HIV) Seroconversions in a Large Prospective Implementation Cohort Study of Oral HIV Preexposure Prophylaxis in Men Who Have Sex with Men (EPIC-NSW).

BACKGROUND: Most human immunodeficiency virus (HIV) seroconversions in people who have initiated preexposure prophylaxis (PrEP) occur in the context of insufficient adherence. We describe participants who seroconverted after being dispensed PrEP in a large PrEP implementation study in Australia. METHODS: Expanded PrEP Implementation in Communities in New South Wales was an implementation study of daily oral PrEP in individuals aged ≥18 years at high risk for acquiring HIV. HIV seroconversions were defined as a positive HIV test by either antigen, antibody, or detectable HIV viral load after enrollment. Insufficient adherence, measured by dispensing logs or participant self-report, was defined as <4 PrEP doses per week. RESULTS: A total of 9596 participants were enrolled and dispensed PrEP between 1 March 2016 and 30 April 2018; 30 were diagnosed with HIV by 31 March 2019. The median (interquartile range [IQR]) age was 31 (25-38) years, all identified as male, 29 (97%) identified as gay or homosexual, and 20 (69%) lived in a postcode with a low concentration of gay male residents. The median (IQR) days from first PrEP dispensing to diagnosis was 409 (347-656). There was no evidence that participants who seroconverted had been sufficiently adherent to PrEP. Nineteen (63%) participants who seroconverted were diagnosed with chlamydia, gonorrhoea, syphilis, or new hepatitis C infection. One participant had resistance to emtricitabine (M184V mutation) at diagnosis. CONCLUSIONS: Participants who seroconverted were insufficiently adherent to PrEP despite being at high risk for acquiring HIV. Understanding the reasons for poor PrEP adherence in individuals who subsequently acquire HIV is critical to improving PrEP effectiveness.

Brief Report: Improvement in Metabolic Health Parameters at Week 48 After Switching From a Tenofovir Alafenamide-Based 3- or 4-Drug Regimen to the 2-Drug Regimen of Dolutegravir/Lamivudine: The TANGO Study.

BACKGROUND: In TANGO, switching to dolutegravir/lamivudine was noninferior at 48 weeks to continuing 3-/4-drug tenofovir alafenamide-based regimens in virologically suppressed individuals with HIV-1. Antiretroviral agents have been associated with weight gain and metabolic complications. SETTING: One hundred thirty-four centers; 10 countries. METHODS: We assessed weight; fasting lipids, glucose, and insulin; and prevalence of insulin resistance and metabolic syndrome at baseline and week 48 in TANGO participant subgroups by boosting agent use in baseline regimens (boosted and unboosted). RESULTS: In each treatment group, 74% of participants used boosted regimens at baseline. In boosted and unboosted subgroups, weight and fasting glucose changes at week 48 were small and similar between treatment groups. Overall and in the boosted subgroup, greater decreases from baseline were observed with dolutegravir/lamivudine in fasting total cholesterol (P < 0.001), low-density lipoprotein cholesterol (P < 0.001), triglycerides (P < 0.001), total cholesterol/high-density lipoprotein cholesterol ratio (overall, P = 0.017; boosted, P = 0.007), and insulin (boosted, P = 0.005). Prevalence of HOMA-IR ≥2 was significantly lower at week 48 with dolutegravir/lamivudine overall [adjusted odds ratio (aOR), 0.59; 95% confidence interval (CI), 0.40 to 0.87; P = 0.008] and in the boosted subgroup [aOR, 0.56; 95% CI, 0.36 to 0.88; P = 0.012] but not in the unboosted subgroup [aOR, 0.70; 95% CI, 0.31 to 1.58; P = 0.396]. Prevalence of metabolic syndrome at week 48 was low and consistent between treatment groups overall, with differences trending to favor dolutegravir/lamivudine in the unboosted subgroup [aOR, 0.41; 95% CI, 0.15 to 1.09; P = 0.075]. CONCLUSION: Generally, switching from 3-/4-drug tenofovir alafenamide-based regimens to dolutegravir/lamivudine improved metabolic parameters, particularly when switching from boosted regimens. Because of smaller sample size in the unboosted subgroup, results warrant further investigation.

Trends in practice: attitudes and challenges in the diagnosis, treatment and management of HIV infection in Australia.

As life expectancy for people living with human immunodeficiency virus (HIV) (PLWHIV) increases, management models for HIV infection are changing. To understand approaches to practice within this shifting climate and across different medical settings, in 2017 we conducted a baseline survey among the main medical practitioner groups responsible for HIV-infection care in Australia: hospital-based physicians (HBP), sexual health physicians (SHP) and 'accredited general practitioners' (referred to in 2017 study as 's100 GPs'), who are GPs authorised to prescribe HIV therapies after completing accredited national training. The follow-up survey presented here explores any changes in approaches, attitudes and challenges associated with HIV-infection management among the same practitioner groups: 17 HBP, 15 SHP and 69 accredited GP (referred to throughout as GP; includes those with sexual health diploma). Analysis of survey results showed practices remained largely similar between surveys, with a few notable exceptions. Greater consistency in attitudes, knowledge and approaches was observed between the practitioner specialty groups, with only small differences between modes of practice. A trend towards earlier initiation of HIV treatment was also identified, with a higher proportion of practitioners than baseline reporting they were comfortable beginning therapy on the day of HIV diagnosis. The impact of the introduction of two-drug therapy in Australia was also explored. Although the majority of survey respondents (and SHP in particular) expressed greater preference for three-drug compared with two-drug regimens, interest in two-drug regimens appears to be growing and may influence future prescribing practices. Addressing mental health issues for PLWHIV was again highlighted as a major priority, with practitioners overwhelmingly reporting mental health management as among their most difficult clinical challenges. Reduction in stigma/discrimination and better access to substance dependency programmes were also identified as unmet needs for this patient cohort. Consistent with our baseline survey, it appears targeted interventions and supports appropriate to this population are still required to improve overall wellbeing for PLWHIV.

Utility of rapid plasmin reagin titres in assessing treatment response and re-infection for infectious syphilis.

Background The rapid plasma reagin (RPR) assay is commonly used as a surrogate marker of infectious syphilis, but is non-specific, slow to change and variable in its rate of decline post treatment. METHODS: Within an urban sexual health service testing predominantly men who have sex with men, a file review of RPR changes was undertaken in all subjects who had a dilution level of ≥1:4, between January 2015 to the end of December 2018. RESULTS: Overall, 248 cases of infectious syphilis were identified in 215 subjects (165 HIV seropositive, 50 HIV seronegative). Among unique-subject cases with follow-up RPR recorded, seroreversion to a non-reactive titre was achieved in only 42.3% (71/168) cases at a median of 235 days (interquartile range: 138-348 days) and was significantly less likely if patients had HIV infection (P = 0.02), late latent syphilis (P = 0.003) or a subsequent syphilis infection (P < 0.0001). Having HIV infection (P = 0.03) or a subsequent episode of syphilis (P = 0.01) were associated with a lower likelihood of documented cure. CONCLUSIONS: The slow decay in RPR titres post therapy and the inability of a significant number of subjects to achieve a non-reactive result over time makes RPR a poor test for assessing the adequacy of treatment or in diagnosing re-infection, especially in populations having repeated and frequent risk exposures. As the number of syphilis cases continue to climb, better tests that accurately assess pathogen presence are urgently needed.

Doravirine dose selection and 96-week safety and efficacy versus efavirenz in antiretroviral therapy-naive adults with HIV-1 infection in a Phase IIb trial.

BACKGROUND: The safety and efficacy of doravirine were compared with that of efavirenz as initial treatment of adults living with HIV-1 infection (NCT01632345). METHODS: A Phase IIb double-blind trial with participants stratified by screening HIV-1 RNA (≤ or >100,000 copies/ml) and randomized 1:1:1:1:1 to receive once-daily doravirine (25, 50, 100 or 200 mg) or efavirenz 600 mg (Part I) for up to 96 weeks, with open-label tenofovir disoproxil fumarate 300 mg/emtricitabine 200 mg (TDF/FTC). After dose selection at week 24, doravirine 100 mg was provided to participants receiving the other doses of doravirine and additional participants were randomized 1:1 to receive once-daily doravirine 100 mg or efavirenz 600 mg for 96 weeks with TDF/FTC (Part II). Primary outcomes were the proportion of participants with HIV-1 RNA <40 copies/ml at week 24, and central nervous system (CNS) adverse events (AEs) by weeks 8 and 24 (Parts I+II combined). RESULTS: 210 and 132 participants were randomized in Parts I and II, respectively, and 216 (108 on doravirine 100 mg, 108 on efavirenz) were evaluable for Parts I+II combined. At week 24, the proportion of participants with HIV-1 RNA <40 copies/ml was 72.9% for doravirine 100 mg and 73.1% for efavirenz (difference -0.5 [95% CI -12.3, 11.2]). In addition, CNS AEs were reported by 26.9% and 47.2% of doravirine and efavirenz recipients, respectively (difference -20.4 [95% CI -32.6, -7.5]; P=0.002). CONCLUSIONS: Doravirine 100 mg with TDF/FTC demonstrated similar antiretroviral activity and superior CNS safety compared with efavirenz 600 mg with TDF/FTC.

Rapid HIV testing increases testing frequency among gay and bisexual men: a controlled before-after study.

Background Rapid HIV testing was introduced at 12 clinics in New South Wales (NSW) for routine testing and promoted with social marketing. The effect of the availability of rapid HIV testing on testing frequency among gay and bisexual men (GBM) was evaluated. METHODS: An observational design using patient data from 12 clinics was used. The primary outcome was the mean number of HIV tests in 12 months. The intervention group comprised GBM who had one or more rapid tests from October 2013 to September 2014 and this was compared with two control groups; a concurrent group (no rapid test in the same period) and a historical group (attended between July 2011 and June 2012). Independent sample t-tests were conducted to compare mean number of tests among men in the intervention, concurrent and historical groups. Multivariate logistic regression was used to assess the association between rapid HIV testing and testing frequency. RESULTS: Men in the intervention group (n = 3934) had a mean of 1.8 HIV tests in 12 months, compared with 1.4 in the concurrent group (n = 5063; P < 0.001) and 1.4 in the historical group (n = 5904; P < 0.001); testing frequency was higher among men at increased risk of HIV in the intervention group compared with the other two groups (mean 2.2, 1.6 and 1.5 respectively; P < 0.001). Membership of the intervention group was associated with increased odds of having two or more HIV tests in 12 months (AOR = 2.5, 95%CI 2.2-2.8; P < 0.001) compared with the concurrent group, after controlling for demographic and behavioural factors. CONCLUSION: Introducing and promoting rapid HIV testing in clinics in NSW was associated with increased HIV testing frequency among GBM.

Empiric antimicrobial treatment for asymptomatic sexual contacts of sexually transmitted infection in the era of antimicrobial resistance: time to rethink?

Prudent prescribing of antimicrobials is essential in ameliorating the public health problem of antimicrobial resistance. This retrospective audit assesses whether empiric antimicrobial treatment for asymptomatic sexual contacts of sexually transmitted infection is appropriate based on laboratory confirmation.

Translation of clinical trial data to changes in clinical practice: rapid transition from tenofovir disoproxil fumarate to tenofovir alafenamide-based therapies in a Sydney HIV clinic.

The transition of clinical trial data to changes in routine clinical practice is often a slow process. We describe a rapid transition of patients from one form of antiviral therapy to a modified and potentially safer version that can occur quickly when there are no financial or organisational restrictions on the prescribers.

Non-AIDS complexity amongst patients living with HIV in Sydney: risk factors and health outcomes.

OBJECTIVE: To assess the prevalence of non-AIDS co-morbidities (NACs) and predictors of adverse health outcomes amongst people living with HIV in order to identify health needs and potential gaps in patient management. DESIGN: Retrospective, non-consecutive medical record audit of patients attending a publicly funded HIV clinic in metropolitan Sydney analysed for predictors of adverse health outcomes. We developed a scoring system based on the validated Charlson score method for NACs, mental health and social issues and confounders were selected using directed acyclic graph theory under the principles of causal inference. RESULTS: 211 patient files were audited non-consecutively over 6 weeks. 89.5% were male; 41.8% culturally and linguistically diverse and 4.1% were of Aboriginal/Torres Strait Islander origin. Half of patients had no general practitioner and 25% were ineligible for Medicare subsidised care. The most common NACs were: cardiovascular disease (25%), hepatic disease (21%), and endocrinopathies (20%). One-third of patients had clinical anxiety, one-third major depression and almost half of patients had a lifetime history of tobacco smoking. Five predictors of poor health outcomes were identified: (1) co-morbidity score was associated with hospitalisation (odds ratio, OR 1.58; 95% CI 1.01-2.46; p = 0.044); (2) mental health score was associated with hospitalisation (OR 1.79; 95% CI 1.22-2.62; p = 0.003) and poor adherence to ART (OR 2.34; 95% CI 1.52-3.59; p = 0.001); (3) social issues score was associated with genotypic resistance (OR 2.61; 95% CI 1.48-4.59; p = 0.001), co-morbidity score (OR 1.69; 95% CI 1.24-2.3; p = 0.001) and hospitalisation (OR 1.72; 95% CI 1.1-2.7; p = 0.018); (4) body mass index < 20 was associated with genotypic resistance (OR 6.25; 95% CI 1.49-26.24; p = 0.012); and (5) Medicare eligibility was associated with co-morbidity score (OR 2.21; 95% CI 1.24-3.95; p = 0.007). CONCLUSION: Most HIV patients are healthy due to effective antiretroviral therapy; however, NACs and social/mental health issues are adding to patient complexity. The current findings underpin the need for multidisciplinary management beyond routine viral load and CD4 count monitoring.

Funding antiretroviral treatment for HIV-positive temporary residents in Australia prevents transmission and is inexpensive.

Background The aim of this study is to estimate the reduction in new HIV infections and resultant cost outcomes of providing antiretroviral treatment (ART) through Australia's 'universal access' health scheme to all temporary residents with HIV infection living legally in Australia, but currently deemed ineligible to access subsidised ART via this scheme. METHODS: A mathematical model to estimate the number of new HIV infections averted and the associated lifetime costs over 5 years if all HIV-positive temporary residents in Australia had access to ART and subsidised medical care was developed. Input data came from a cohort of 180 HIV-positive temporary residents living in Australia who are receiving free ART donated by pharmaceutical companies for up to 4 years. RESULTS: Expanding ART access to an estimated total 450 HIV+ temporary residents in Australia for 5 years could avert 80 new infections. The model estimated the total median discounted (5%) cost for ART and associated care to be A$36million, while the total savings in lifetime-discounted costs for the new infections averted was A$22million. CONCLUSIONS: It is estimated that expanded access to ART for all HIV-positive temporary residents in Australia will substantially reduce HIV transmission to their sexual partners at little additional cost. In the context of Australia's National HIV strategy and Australia's endorsement of global goals to provide universal access to ART for all people with HIV, this is an important measure to remove inequities in the provision of HIV-related treatment and care.

Concomitant medication polypharmacy, interactions and imperfect adherence are common in Australian adults on suppressive antiretroviral therapy.

OBJECTIVES: We quantified concomitant medication polypharmacy, pharmacokinetic and pharmacodynamic interactions, adverse effects and adherence in Australian adults on effective antiretroviral therapy. DESIGN: Cross-sectional. METHODS: Patients recruited into a nationwide cohort and assessed for prevalence and type of concomitant medication (including polypharmacy, defined as ≥5 concomitant medications), pharmacokinetic or pharmacodynamic interactions, potential concomitant medication adverse effects and concomitant medication adherence. Factors associated with concomitant medication polypharmacy and with imperfect adherence were identified using multivariable logistic regression. RESULTS: Of 522 participants, 392 (75%) took a concomitant medication (mostly cardiovascular, nonprescription or antidepressant). Overall, 280 participants (54%) had polypharmacy of concomitant medications and/or a drug interaction or contraindication. Polypharmacy was present in 122 (23%) and independently associated with clinical trial participation, renal impairment, major comorbidity, hospital/general practice-based HIV care (versus sexual health clinic) and benzodiazepine use. Seventeen participants (3%) took at least one concomitant medication contraindicated with their antiretroviral therapy, and 237 (45%) had at least one pharmacokinetic/pharmacodynamic interaction. Concomitant medication use was significantly associated with sleep disturbance and myalgia, and polypharmacy of concomitant medications with diarrhoea, fatigue, myalgia and peripheral neuropathy. Sixty participants (12%) reported imperfect concomitant medication adherence, independently associated with requiring financial support, foregoing necessities for financial reasons, good/very good self-reported general health and at least 1 bed day for illness in the previous 12 months. CONCLUSION: In a resource-rich setting with universal healthcare access, the majority of this sample took a concomitant medication. Over half had at least one of concomitant medication polypharmacy, pharmacokinetic or pharmacodynamic interaction. Concomitant medication use was associated with several adverse clinical outcomes.

Overlapping HIV prevention strategies; case report of pre-exposure and postexposure prophylaxes used for a single risk event between two men.

A range of prevention strategies have been considered in an attempt to reduce HIV transmission. The use of continuous antiretrovirals (ARVs) in high-risk HIV-negative individuals (pre-exposure prophylaxis or PrEP) and the short-term use of ARVs following a high-risk exposure (postexposure prophylaxis or PEP) are among these strategies. We report a case of the contemporaneous use of PEP and PrEP in a sexual liaison between two men.In an attempt to reduce the number of new cases of HIV infection, a range of prevention strategies have been advocated. Prior to the availability of ARV therapy, the key prevention measure was condom promotion and modifying sexual behaviour such as partner number reduction within high-risk groups. This was followed by: the introduction of PEP, treating all HIV cases with ARVs to reduce the probability of transmission (treatment as prevention) and in the past few years the use of PrEP. Case-control, observational and randomised clinical trial data exist to support these strategies. We describe what we believe is the first reported use of PrEP and PEP in a sexual liaison between two men in Sydney.

Patient-reported outcomes in the single-tablet regimen (STaR) trial of rilpivirine/emtricitabine/tenofovir disoproxil fumarate versus efavirenz/emtricitabine/tenofovir disoproxil fumarate in antiretroviral treatment-naive adults infected with HIV-1 through 48 weeks of treatment.

This 96-week, randomized, open-label study was designed to assess the efficacy and safety of two single-tablet regimens in treatment naïve HIV-1-infected adults: rilpivirine (RPV) + emtricitabine/tenofovir disoproxil fumarate (FTC/TDF) and efavirenz (EFV) + FTC/TDF. Assessments included patient-reported Medication Adherence Self-Report Inventory, SF-12v2 Quality of Life assessment, HIV Treatment Satisfaction Questionnaire, and HIV Symptom Index Questionnaire through Week 48. Additional evaluations included study drug discontinuations due to treatment-emergent adverse events (TEAEs). A total of 786 participants (n=394 RPV/FTC/TDF, n=392 EFV/FTC/TDF) were included. Fewer RPV/FTC/TDF-treated than EFV/FTC/TDF-treated participants discontinued study drug due to TEAEs (2.5% vs. 8.7%), with 41% (14/34) TEAE-related discontinuations in the EFV/FTC/TDF group occurring within the first four weeks of treatment. Treatment adherence and satisfaction remained high through Week 48 and quality of life improved from baseline in both groups. There were no significant between-group differences in virologic success (HIV-1 RNA <50 copies/mL) regardless of adherence (<95% or ≥95%). Significant between-group differences favouring RPV/FTC/TDF were observed for the HIV SIQ symptoms of difficulty falling or staying asleep (p = .022) and diarrhea or loose bowel movements (p = .002). In conclusion, 48-week treatment with RPV/FTC/TDF or EFV/FTC/TDF was associated with high adherence, high treatment satisfaction, and improved quality of life. TEAE-related discontinuations and patient-reported symptoms indicate that RPV/FTC/TDF may be somewhat better tolerated than EFV/FTC/TDF.

Barriers to HIV testing and characteristics associated with never testing among gay and bisexual men attending sexual health clinics in Sydney.

INTRODUCTION: HIV diagnoses among gay and bisexual men have increased over the past decade in Australia. HIV point-of-care testing (POCT) was introduced in Australia in 2011 as a strategy to increase HIV testing by making the testing process more convenient. We surveyed gay and bisexual men undergoing POCT to assess barriers to HIV testing and characteristics associated with not having previously tested for HIV (never testing). METHODS: During 2011 and 2012, gay and bisexual men who were undergoing POCT at four Sydney sexual health clinics self-completed questionnaires assessing testing history and psychological and structural barriers to HIV testing. Bivariate and multivariate logistic regression was used to assess associations between patient characteristics and never testing. RESULTS: Of 1093 participants, 981 (89.9%) reported ever testing for HIV and 110 (10.1%) never testing. At least one barrier to testing was reported by 1046 men (95.7%), with only 47 men (4.3%) not reporting any barrier to testing. The most commonly reported barriers to testing were annoyance at having to return for results (30.2%), not having done anything risky (29.6%), stress in waiting for results (28.4%), being afraid of testing positive (27.5%) and having tested recently (23.2%). Never testing was independently associated with being non-gay-identified (adjusted odds ratio [AOR]: 1.9; 95% confidence interval [CI]: 1.1-3.2), being aged less than 25 years (AOR: 2.4; 95% CI: 1.6-3.8), living in a suburb with few gay couples (AOR: 1.9; 95% CI: 1.2-3.0), being afraid of testing HIV-positive (AOR: 1.6; 95% CI: 1.0-2.4), not knowing where to test (AOR: 3.8; 95% CI: 1.3-11.2) and reporting one or no sexual partners in the last six months (AOR: 2.7; 95% CI: 1.2-6.2). CONCLUSIONS: Barriers to HIV testing were commonly reported among the clinic-based gay and bisexual men in this study. Our findings suggest further health promotion and prevention strategies are needed to address the knowledge, attitudes and behavioural factors associated with never testing.

Rapid HIV Testing Is Highly Acceptable and Preferred among High-Risk Gay And Bisexual Men after Implementation in Sydney Sexual Health Clinics.

BACKGROUND: Rapid HIV testing (RHT) is well established in many countries, but it is new in Australia. We assessed the acceptability of RHT and its associations among gay, bisexual and other men who have sex with men (GBM) after implementation of RHT in Sydney sexual health clinics. METHODS: GBM were invited to complete an acceptability questionnaire before and after provision of the result of finger-prick blood RHT, comparing their experience of RHT with conventional HIV testing (CHT) involving venipuncture. Logistic regression was used to assess associations between patient characteristics and the preference for RHT over CHT next time they tested for HIV. RESULTS: Of 1061 GBM who received non-reactive RHT results, 59% found RHT less stressful than CHT and 34% reported no difference, and 61% found RHT more comfortable than CHT and 26% reported no difference. Nearly all men were satisfied with RHT result delivery (99%) and the RHT process overall (99%). Most men (79%) preferred RHT for their next HIV test and this preference was stronger in men who were aged 35-44 years (adjusted odds ratio [AOR] 2.49, p<0.01), reported they would test more often if RHT was available (AOR 1.66, p=0.01), found returning for results annoying (AOR 1.67, p=0.01), and found RHT less stressful (AOR 2.37, p<0.01) and more comfortable (AOR 1.62, p=0.02) than CHT. Men concerned about the reliability of RHT were less than half as likely to prefer RHT for their next HIV test (AOR 0.44, p<0.01). CONCLUSIONS: Most GBM preferred RHT to CHT next time and this preference was associated with finding RHT more convenient, more comfortable and less stressful than CHT. These findings suggest that in a clinic setting RHT should be considered to improve the patient experience and may potentially increase uptake and frequency of HIV testing.

Multi-centre evaluation of the Determine HIV Combo assay when used for point of care testing in a high risk clinic-based population.

BACKGROUND: Determine HIV Combo (DHC) is the first point of care assay designed to increase sensitivity in early infection by detecting both HIV antibody and antigen. We conducted a large multi-centre evaluation of DHC performance in Sydney sexual health clinics. METHODS: We compared DHC performance (overall, by test component and in early infection) with conventional laboratory HIV serology (fourth generation screening immunoassay, supplementary HIV antibody, p24 antigen and Western blot tests) when testing gay and bisexual men attending four clinic sites. Early infection was defined as either acute or recent HIV infection acquired within the last six months. RESULTS: Of 3,190 evaluation specimens, 39 were confirmed as HIV-positive (12 with early infection) and 3,133 were HIV-negative by reference testing. DHC sensitivity was 87.2% overall and 94.4% and 0% for the antibody and antigen components, respectively. Sensitivity in early infection was 66.7% (all DHC antibody reactive) and the DHC antigen component detected none of nine HIV p24 antigen positive specimens. Median HIV RNA was higher in false negative than true positive cases (238,025 vs. 37,591 copies/ml; p = 0.022). Specificity overall was 99.4% with the antigen component contributing to 33% of false positives. CONCLUSIONS: The DHC antibody component detected two thirds of those with early infection, while the DHC antigen component did not enhance performance during point of care HIV testing in a high risk clinic-based population.

What proportion of sexually transmissible infections and HIV are diagnosed in New South Wales' public sexual health services compared with other services?

BACKGROUND: In New South Wales (NSW), publicly funded sexual health services (PFSHSs) target the populations at greatest risk for important sexually transmissible infections (STIs) and so may make a large contribution to the diagnosis of notifiable STIs. We aimed to determine the proportions of STIs diagnosed in PFSHSs and notified to the NSW Ministry of Health in 2009, and describe geographical variations. METHODS: The number of notifiable STIs (infectious syphilis, gonorrhoea, HIV and chlamydia) diagnosed in 2009 was obtained for each Area Health Service (AHS) and each PFSHS. The proportion of diagnoses made by PFSHSs was calculated at the state and AHS level according to five geographical regions: inner and outer metropolitan, regional, rural and remote. RESULTS: The overall proportions of diagnoses made by NSW PFSHSs were syphilis, 25%; gonorrhoea, 25%; HIV, 21%; and chlamydia, 14%. Within each zone, the proportions of these STIs were (respectively): (i) inner metropolitan: 32%, 26%, 21% and 13%; (ii) outer metropolitan: 41%, 24%, 43% and 9%; (iii) regional: 62%, 15%, 23% and 10%; (iv) rural: 8%, 29%, <5% and 20%; and (v) remote: <5%, 43%, <5% and 29%. There was considerable variation in proportions of STIs between and within AHSs (<5-100%). CONCLUSIONS: NSW PFSHSs contribute a large proportion of diagnoses for syphilis, gonorrhoea and HIV, but less so for chlamydia. Across AHSs and zones, there was considerable variation in the proportions. These data support the role of PFSHS in identifying and managing important STIs in high-risk populations.

Case report and evaluation of the frequency of the prozone phenomenon in syphilis serology - an infrequent but important laboratory phenomenon.

BACKGROUND: Treponema pallidum specific serology generally remains reactive for life. Therefore, the diagnosis of syphilis reinfection relies on clinical assessment and nontreponemal (reagin) serologic testing. The prozone phenomenon can lead to a falsely nonreactive rapid plasma reagin (RPR) assay result. METHODS: We report a case of secondary syphilis in a HIV infected patient with a previous history of syphilis infection, where a falsely nonreactive RPR assay was associated with a delayed diagnosis of reinfection and infectious syphilis. The prozone phenomenon was detected in several of the patient's serum samples collected around this time. We subsequently undertook a prospective evaluation for the prozone phenomenon in 3222 consecutive sera, which were assayed using the RPR assay for clinical purposes over a 10-month period. RESULTS: The overall rate of the prozone phenomenon was 2 out of 3222 samples (0.06%; 95% confidence interval (CI): 0.02-0.22%) and the rate per reactive sample was 2 out of 397 (0.5%; 95% CI: 0.14-1.81%). CONCLUSION: Clinicians should request RPR testing at dilutions of sera when syphilis is suspected clinically and the RPR assay is nonreactive.