Monitoring HIV pre-exposure prophylaxis (PrEP) uptake in Australia: Issue #8, May 2023

HIV pre-exposure prophylaxis (PrEP) was listed on the Pharmaceutical Benefits Scheme (PBS) on 1 April 2018. The PBS subsidises the cost of PrEP for people eligible for Medicare in Australia. The cost to the patient for 30 pills as of May 2023 was $30.00 for general patients and$7.30 for concession card holders. This report uses data from every PBS-subsidised PrEP prescription that was dispensed in Australia between 1 April 2018 and 31 December 2022. The de-identified data incorporate unique codes for linking individuals. Variables include patient details (age, sex, postcode of residence, concession status), information about dispensing (date of dispensing, quantity dispensed), and prescriber details (postcode, specialty). Data are presented on the total number of people who have ever initiated PBS-subsidised PrEP, as well as the number of people dispensed PrEP within each quarter, and within the past 12 months. These data are disaggregated by age, and by state or territory of patient residence, and presented as population rates. This report also includes a section investigating the effect of COVID-19-related lockdowns on monthly dispensing data by jurisdiction

The impact of blood donation deferral strategies on the eligibility of men who have sex with men and other sexual risk behavior in Australia

Background In Australia, a man cannot donate blood if he has had sex with another man within the past 3 months. However, this policy has been criticized as being discriminatory as it does not consider lower risk subgroups, and led to calls for modifications to the policy that more accurately distinguish risk among gay, bisexual, and other men who have sex with men (GBM). Study Design and Methods We used data from a nationally representative survey to estimate the proportion of GBM aged 18–74 years old who would be eligible to donate under current criteria and other scenarios. Results Among the 5178 survey participants, 155 (3.0%) were classified as GBM based on survey responses, Among the GBM, 40.2% (95% CI 28.0%–53.7%) were eligible to donate based on current criteria, and 21.0% (95% CI 14.5%–29.5%) were ineligible due to the 3 months deferral alone. Eligibility among GBM, all men, and the population increased as criteria were removed. Under the new Australian plasma donation criteria, 73.6% (95% CI 64.4%–81.1%) of GBM, 68.4% (95% CI 65.5%–71.2%) of all men, and 60.8% (95% CI 58.8%–62.8%) of the full population were estimated to be eligible. Only 16.1% (95% CI 8.6%–28.1%) of GBM knew that the male-to-male sex deferral period is 3 months. Discussion Changing the deferral criteria and sexual risk evaluation would lead to a higher proportion of GBM being eligible to donate blood. Knowledge of the current GBM deferral period is very low. Improved education about the current criteria and any future changes are required to improve blood donation rates

Antiretroviral treatment use, co-morbidities and clinical outcomes among Aboriginal participants in the Australian HIV Observational Database (AHOD)

Background: There are few data regarding clinical care and outcomes of Indigenous Australians living with HIV and it is unknown if these differ from non-Indigenous HIV-positive Australians. Methods: AHOD commenced enrolment in 1999 and is a prospective cohort of HIV-positive participants attending HIV outpatient services throughout Australia, of which 20 (74 %) sites report Indigenous status. Data were collected up until March 2013 and compared between Indigenous and non-Indigenous participants. Person-year methods were used to compare death rates, rates of loss to follow-up and rates of laboratory testing during follow-up between Indigenous and non-Indigenous participants. Factors associated with time to first combination antiretroviral therapy (cART) regimen change were assessed using Kaplan Meier and Cox Proportional hazards methods. Results: Forty-two of 2197 (1.9 %) participants were Indigenous. Follow-up amongst Indigenous and non-Indigenous participants was 332 & 16270 person-years, respectively. HIV virological suppression was achieved in similar proportions of Indigenous and non-Indigenous participants 2 years after initiation of cART (81.0 % vs 76.5 %, p = 0.635). Indigenous status was not independently associated with shorter time to change from first- to second-line cART (aHR 0.95, 95 % CI 0.51-1.76, p = 0.957). Compared with non-Indigenous participants, Indigenous participants had significantly less frequent laboratory monitoring of CD4 count (rate:2.76 tests/year vs 2.97 tests/year, p = 0.025) and HIV viral load (rate:2.53 tests/year vs 2.93 tests/year, p < 0.001), while testing rates for lipids and blood glucose were almost half that of non-indigenous participants (rate:0.43/year vs 0.71 tests/year, p < 0.001). Loss to follow-up (23.8 % vs 29.8 %, p = 0.496) and death (2.4 % vs 7.1 %, p = 0.361) occurred in similar proportions of indigenous and non-Indigenous participants, respectively, although causes of death in both groups were mostly non-HIV-related. Conclusions: As far as we are aware, these are the first data comparing clinical outcomes between Indigenous and non-Indigenous HIV-positive Australians. The forty-two Indigenous participants represent over 10 % of all Indigenous Australians ever diagnosed with HIV. Although outcomes were not significantly different, Indigenous patients had lower rates of laboratory testing for HIV and lipid/glucose parameters. Given the elevated risk of cardiovascular disease in the general Indigenous community, the additional risk factor of HIV infection warrants further focus on modifiable risk factors to maximise life expectancy in this population

Local immune responses of the Chinese water buffalo, Bubalus bubalis, against Schistosoma japonicum larvae: crucial insights for vaccine design

Asian schistosomiasis is a zoonotic parasitic disease infecting up to a million people and threatening tens of millions more. Control of this disease is hindered by the animal reservoirs of the parasite, in particular the water buffalo (Bubalus bubalis), which is responsible for significant levels of human transmission. A transmission-blocking vaccine administered to buffaloes is a realistic option which would aid in the control of schistosomiasis. This will however require a better understanding of the immunobiology of schistosomiasis in naturally exposed buffaloes, particularly the immune response to migrating schistosome larvae, which are the likely targets of an anti-schistosome vaccine. To address this need we investigated the immune response at the major sites of larval migration, the skin and the lungs, in previously exposed and re-challenged water buffaloes. In the skin, a strong allergic-type inflammatory response occurred, characterised by leukocyte and eosinophil infiltration including the formation of granulocytic abscesses. Additionally at the local skin site, interleukin-5 transcript levels were elevated, while interleukin-10 levels decreased. In the skin-draining lymph node (LN) a predominant type-2 profile was seen in stimulated cells, while in contrast a type-1 profile was detected in the lung draining LN, and these responses occurred consecutively, reflecting the timing of parasite migration. The intense type-2 immune response at the site of cercarial penetration is significantly different to that seen in naive and permissive animal models such as mice, and suggests a possible mechanism for immunity. Preliminary data also suggest a reduced and delayed immune response occurred in buffaloes given high cercarial challenge doses compared with moderate infections, particularly in the skin. This study offers a deeper understanding into the immunobiology of schistosomiasis in a natural host, which may aid in the future design of more effective vaccines

Kidney function in tenofovir disoproxil fumarate-based oral pre-exposure prophylaxis users: a systematic review and meta-analysis of published literature and a multi-country meta-analysis of individual participant data

BACKGROUND: Previous WHO guidance on tenofovir disoproxil fumarate-based oral pre-exposure prophylaxis (PrEP) suggests measuring creatinine levels at PrEP initiation and regularly afterwards, which might represent barriers to PrEP implementation and uptake. We aimed to systematically review published literature on kidney toxicity among tenofovir disoproxil fumarate-based oral PrEP users and conducted an individual participant data meta-analysis (IPDMA) on kidney function among PrEP users in a global implementation project dataset. METHODS: In this systematic review and meta-analysis we searched PubMed up to June 30, 2021, for randomised controlled trials (RCTs) or cohort studies that reported on graded kidney-related adverse events among oral PrEP users (tenofovir disoproxil fumarate-based PrEP alone or in combination with emtricitabine or lamivudine). We extracted summary data and conducted meta-analyses with random-effects models to estimate relative risks of grade 1 and higher and grade 2 and higher kidney-related adverse events, measured by elevated serum creatinine or decline in estimated creatinine clearance or estimated glomerular filtration rate. The IPDMA included (largely unpublished) individual participant data from 17 PrEP implementation projects and two RCTs. Estimated baseline creatinine clearance and creatinine clearance change after initiation were described by age, gender, and comorbidities. We used random-effects regressions to estimate the risk in decline of creatinine clearance to less than 60 mL/min. FINDINGS: We identified 62 unique records and included 17 articles reporting on 11 RCTs with 13 523 participants in meta-analyses. PrEP use was associated with increased risk of grade 1 and higher kidney adverse events (pooled odds ratio [OR] 1·49, 95% CI 1·22-1·81; I2=25%) and grade 2 and higher events (OR 1·75, 0·68-4·49; I2=0%), although the grade 2 and higher association was not statistically significant and events were rare (13 out of 6764 in the intervention group vs six out of 6782 in the control group). The IPDMA included 18 676 individuals from 15 countries (1453 [7·8%] from RCTs) and 79 (0·42%) had a baseline estimated creatinine clearance of less than 60 mL/min (increasing proportions with increasing age). Longitudinal analyses included 14 368 PrEP users and 349 (2·43%) individuals had a decline to less than 60 mL/min creatinine clearance, with higher risks associated with increasing age and baseline creatinine clearance of 60·00-89·99 mL/min (adjusted hazard ratio [aHR] 8·49, 95% CI 6·44-11·20) and less than 60 mL/min (aHR 20·83, 12·83-33·82). INTERPRETATION: RCTs suggest that risks of kidney-related adverse events among tenofovir disoproxil fumarate-based oral PrEP users are increased but generally mild and small. Our global PrEP user analysis found varying risks by age and baseline creatinine clearance. Kidney function screening and monitoring might focus on older individuals, those with baseline creatinine clearance of less than 90 mL/min, and those with kidney-related comorbidities. Less frequent or optional screening among younger individuals without kidney-related comorbidities may reduce barriers to PrEP implementation and use. FUNDING: Unitaid, Bill & Melinda Gates Foundation, WHO

Trends in detectable viral load by calendar year in the Australian HIV observational database

Background Recent papers have suggested that expanded combination antiretroviral treatment (cART) through lower viral load may be a strategy to reduce HIV transmission at a population level. We assessed calendar trends in detectable viral load in patients recruited to the Australian HIV Observational Database who were receiving cART. Methods Patients were included in analyses if they had started cART (defined as three or more antiretrovirals) and had at least one viral load assessment after 1 January 1997. We analyzed detectable viral load (>400 copies/ml) in the first and second six months of each calendar year while receiving cART. Repeated measures logistic regression methods were used to account for within and between patient variability. Rates of detectable viral load were predicted allowing for patients lost to follow up. Results Analyses were based on 2439 patients and 31,339 viral load assessments between 1 January 1997 and 31 March 2009. Observed detectable viral load in patients receiving cART declined to 5.3% in the first half of 2009. Predicted detectable viral load based on multivariate models, allowing for patient loss to follow up, also declined over time, but at higher levels, to 13.8% in 2009. Conclusions Predicted detectable viral load in Australian HIV Observational Database patients receiving cART declined over calendar time, albeit at higher levels than observed. However, over this period, HIV diagnoses and estimated HIV incidence increased in Australia

Strategies to improve control of sexually transmissible infections in remote Australian Aboriginal communities: a stepped-wedge, cluster-randomised trial

BACKGROUND: Remote Australian Aboriginal communities have among the highest diagnosed rates of sexually transmissible infections (STIs) in the world. We did a trial to assess whether continuous improvement strategies related to sexual health could reduce infection rates. METHODS: In this stepped-wedge, cluster-randomised trial (STIs in remote communities: improved and enhanced primary health care [STRIVE]), we recruited primary health-care centres serving Aboriginal communities in remote areas of Australia. Communities were eligible to participate if they were classified as very remote, had a population predominantly of Aboriginal people, and only had one primary health-care centre serving the population. The health-care centres were grouped into clusters on the basis of geographical proximity to each other, population size, and Aboriginal cultural ties including language connections. Clusters were randomly assigned into three blocks (year 1, year 2, and year 3 clusters) using a computer-generated randomisation algorithm, with minimisation to balance geographical region, population size, and baseline STI testing level. Each year for 3 years, one block of clusters was transitioned into the intervention phase, while those not transitioned continued usual care (control clusters). The intervention phase comprised cycles of reviewing clinical data and modifying systems to support improved STI clinical practice. All investigators and participants were unmasked to the intervention. Primary endpoints were community prevalence and testing coverage in residents aged 16–34 years for Chlamydia trachomatis, Neisseria gonorrhoeae, and Trichomonas vaginalis . We used Poisson regression analyses on the final dataset and compared STI prevalences and testing coverage between control and intervention clusters. All analyses were by intention to treat and models were adjusted for time as an independent covariate in overall analyses. This study was registered with the Australia and New Zealand Clinical Trials Registry, ACTRN12610000358044. FINDINGS: Between April, 2010, and April, 2011, we recruited 68 primary care centres and grouped them into 24 clusters, which were randomly assigned into year 1 clusters (estimated population aged 16–34 years, n=11 286), year 2 clusters (n=10 288), or year 3 clusters (n=13 304). One primary health-care centre withdrew from the study due to restricted capacity to participate. We detected no difference in the relative prevalence of STIs between intervention and control clusters (adjusted relative risk [RR] 0·97, 95% CI 0·84–1·12; p=0·66). However, testing coverage was substantially higher in intervention clusters (22%) than in control clusters (16%; RR 1·38; 95% CI 1·15–1·65; p=0·0006). INTERPRETATION: Our intervention increased STI testing coverage but did not have an effect on prevalence. Additional interventions that will provide increased access to both testing and treatment are required to reduce persistently high prevalences of STIs in remote communities.James Ward, Rebecca J Guy, Alice R Rumbold, Skye McGregor, Handan Wand, Hamish McManus, Amalie Dyda, Linda Garton, Belinda Hengel, Bronwyn J Silver, Debbie Taylor-Thomson, Janet Knox, Basil Donovan, Matthew Law, Lisa Maher, Christopher K Fairley, Steven Skov, Nathan Ryder, Elizabeth Moore, Jacqueline Mein, Carole Reeve, Donna Ah Chee, John Boffa and John M Kaldo