Safety and Efficacy of NVX-CoV2373 Covid-19 Vaccine.

BACKGROUND: Early clinical data from studies of the NVX-CoV2373 vaccine (Novavax), a recombinant nanoparticle vaccine against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that contains the full-length spike glycoprotein of the prototype strain plus Matrix-M adjuvant, showed that the vaccine was safe and associated with a robust immune response in healthy adult participants. Additional data were needed regarding the efficacy, immunogenicity, and safety of this vaccine in a larger population. METHODS: In this phase 3, randomized, observer-blinded, placebo-controlled trial conducted at 33 sites in the United Kingdom, we assigned adults between the ages of 18 and 84 years in a 1:1 ratio to receive two intramuscular 5-µg doses of NVX-CoV2373 or placebo administered 21 days apart. The primary efficacy end point was virologically confirmed mild, moderate, or severe SARS-CoV-2 infection with an onset at least 7 days after the second injection in participants who were serologically negative at baseline. RESULTS: A total of 15,187 participants underwent randomization, and 14,039 were included in the per-protocol efficacy population. Of the participants, 27.9% were 65 years of age or older, and 44.6% had coexisting illnesses. Infections were reported in 10 participants in the vaccine group and in 96 in the placebo group, with a symptom onset of at least 7 days after the second injection, for a vaccine efficacy of 89.7% (95% confidence interval [CI], 80.2 to 94.6). No hospitalizations or deaths were reported among the 10 cases in the vaccine group. Five cases of severe infection were reported, all of which were in the placebo group. A post hoc analysis showed an efficacy of 86.3% (95% CI, 71.3 to 93.5) against the B.1.1.7 (or alpha) variant and 96.4% (95% CI, 73.8 to 99.5) against non-B.1.1.7 variants. Reactogenicity was generally mild and transient. The incidence of serious adverse events was low and similar in the two groups. CONCLUSIONS: A two-dose regimen of the NVX-CoV2373 vaccine administered to adult participants conferred 89.7% protection against SARS-CoV-2 infection and showed high efficacy against the B.1.1.7 variant. (Funded by Novavax; EudraCT number, 2020-004123-16.).

Twelve-month effectiveness and safety of bictegravir/emtricitabine/tenofovir alafenamide in people with HIV: Real-world insights from BICSTaR cohorts.

BACKGROUND: Real-world evidence is an essential component of evidence-based medicine. The aim of the BICSTaR (BICtegravir Single Tablet Regimen) study is to assess effectiveness and safety of bictegravir/emtricitabine/tenofovir alafenamide (B/F/TAF) in antiretroviral treatment-naïve (TN) and treatment-experienced (TE) people with HIV. METHODS: BICSTaR is a prospective, observational cohort study. Participants (≥18 years) are being followed for 24 months. A pooled analysis is presented at 12 months, with the primary endpoint of effectiveness (HIV-1 RNA <50 copies/mL) and secondary endpoints of safety and tolerability (as per protocol). An exploration of patient-reported outcome measures using standardized questionnaires is included. RESULTS: Between June 2018 and May 2021, 1552 people with HIV were enrolled across 12 countries. The analysed population comprised 1509 individuals (279 TN, 1230 TE); most were white (76%), male (84%) and had one or more comorbid conditions (68%). Median age was 47 years. After 12 months of B/F/TAF treatment, HIV-1 RNA was <50 copies/mL in 94% (221/236) of TN participants and 97% (977/1008) of TE participants. Median CD4 cell count increased by 214 cells/µL (p < 0.001) in TN participants and 13 cells/µL (p = 0.014) in TE participants; median CD4/CD8 ratios increased by 0.30 and 0.03, respectively (both p < 0.001). Persistence was high at 12 months (TN, 97%; TE, 95%). No resistance to B/F/TAF emerged. Study drug-related adverse events occurred in 13% of participants through 12 months, leading to B/F/TAF discontinuation in 6%. CONCLUSIONS: The findings of this study provide robust real-world evidence to support the broad use of B/F/TAF in both TN and TE people with HIV.

Multicentre service evaluation of injectable cabotegravir and rilpivirine delivery and outcomes across 12 UK clinics (SHARE LAI-net).

INTRODUCTION: Long-acting injectable cabotegravir + rilpivirine (CAB + RPV LAI) was approved for use in virally suppressed adults in the England and Wales national health service in November 2021. We describe a service evaluation of delivery processes and outcomes in 12 clinics. METHODS: Centres populated a database using information from local policies and clinical records. Services were asked to describe approval processes, clinic pathways, and adherence to national guidelines. Additional data were collected on reasons for regimen choice, treatment discontinuations, and management of viraemia. RESULTS: In total, 518 adults from 12 clinics were approved for CAB + RPV LAI between February 2022 and December 2023. Of the 518 people approved for CAB + RPV LAI, 423 received at least one injection. Median duration on CAB + RPV was 7.5 months (interquartile range 3.7-11.3). In total, 97% of injections were administered within the ±7-day window. Virological failure occurred in 0.7%, and 6% discontinued CAB + RPV. CONCLUSION: In this large UK-based cohort, robust approval processes and clinic protocols facilitated on-time injections and low rates of both discontinuation and virological failure.

Anastrozole as a therapeutic option for gynecomastia in a person receiving antiretroviral therapy: Case report.

A middle-aged Caucasian man living with HIV, clinically stable (viral load <20 copies/mL) on injectable antiretroviral cabotegravir plus rilpivirine every 2 months presented with a 6-month history of bilateral enlargement of the breasts associated with pain. His hormonal profile was normal, and no other underlying cause was identified. He was diagnosed with idiopathic gynecomastia. Tamoxifen is an anti-oestrogen recommended for gynecomastia and has been described in people living with HIV but can potentially induce the activity of cytochrome P450 3A4 (CYP3A4), reducing rilpivirine concentrations, which consequently may cause virological failure and resistance. This is the same for other antiretroviral agents majorly induced by CYP3A4. To date, there have been no reported cases of using anastrozole as a treatment for gynecomastia in people living with HIV or of its co-administration with antiretroviral. We describe the use of an aromatase inhibitor instead of tamoxifen in a person living with HIV, diagnosed with gynecomastia.

A case report highlighting drug-drug interactions between 3 life-saving treatments: Feminizing hormones, antiretrovirals and antituberculosis drugs.

We here present a case providing valuable insights for clinicians who deliver care to patients identifying as transgender or nonbinary. A 30-year-old trans woman presented to sexual health services requesting a routine sexual health screen and was subsequently diagnosed with HIV and syphilis. She started antiretrovirals for HIV (bictegravir/tenoforvir alafenamide/emtricitabine) 12 days later and was treated with benzathine penicillin G. The patient also had a positive tuberculosis (TB) ELIspot blood test result and further investigations proved the presence of active TB in the chest with mediastinal involvement. She commenced treatment for TB with quadruple therapy, including rifampicin. Due to the clinically significant interaction between rifampicin and bictegravir, the patient's antiretroviral treatment was switched to dolutegravir 50 mg twice daily in combination with tenofovir disoproxil fumarate and emtricitabine. As the patient had transitioned from male to female and was self-medicating with oestrogen-containing feminizing hormone therapy, her hormonal treatment was optimized and blood levels of oestradiol were closely monitored and titrated to manage the drug-drug interaction between rifampicin and oestrogen to ensure the latter would be maintained within the expected therapeutic range. Our case report demonstrates the importance of combining treatment of multiple conditions under 1 team ideally integrated with gender services to prevent multiple attendances and mismanagement of feminizing hormone therapies.

Episodic disability questionnaire (EDQ) measurement properties among adults living with HIV in Canada, Ireland, United Kingdom, and United States.

BACKGROUND: The Episodic Disability Questionnaire (EDQ) is a generic 35-item patient-reported outcome measure of presence, severity and episodic nature of disability. We assessed the measurement properties of the Episodic Disability Questionnaire (EDQ) with adults living with HIV. METHODS: We conducted a measurement study with adults living with HIV in eight clinical settings in Canada, Ireland, United Kingdom, and United States. We electronically administered the EDQ followed by three reference measures (World Health Organization Disability Assessment Schedule; Patient Health Questionnaire; Social Support Scale) and a demographic questionnaire. We administered the EDQ only 1 week later. We assessed the internal consistency reliability (Cronbach's alpha; > 0.7 acceptable), and test-retest reliability (Intra Class Correlation Coefficient; > 0.7 acceptable). We estimated required change in EDQ domain scores to be 95% certain that a change was not due to measurement error (Minimum Detectable Change (MDC95%)). We evaluated construct validity by assessing 36 primary hypotheses of relationships between EDQ scores and scores on the reference measures (> 75% hypotheses confirmed indicated validity). RESULTS: Three hundred fifty nine participants completed the questionnaires at time point 1, of which 321 (89%) completed the EDQ approximately 1 week later. Cronbach's alpha for internal consistency ranged from 0.84 (social domain) to 0.91 (day domain) for the EDQ severity scale, and 0.72 (uncertainty domain) to 0.88 (day domain) for the EDQ presence scale, and 0.87 (physical, cognitive, mental-emotional domains) to 0.89 (uncertainty domain) for the EDQ episodic scale. ICCs for test-retest reliability ranged from 0.79 (physical domain) to 0.88 (day domain) for the EDQ severity scale and from 0.71 (uncertainty domain) to 0.85 (day domain) for the EDQ presence scale. Highest precision was demonstrated in the severity scale for each domain (MDC95% range: 19-25 out of 100), followed by the presence (MDC95% range: 37-54) and episodic scales (MDC95% range:44-76). Twenty-nine of 36 (81%) construct validity hypotheses were confirmed. CONCLUSIONS: The EDQ possesses internal consistency reliability, construct validity, and test-retest reliability, with limited precision when administered electronically with adults living with HIV across in clinical settings in four countries. Given the measurement properties, the EDQ can be used for group level comparisons for research and program evaluation in adults living with HIV.

The predictive role of symptoms in COVID-19 diagnostic models: A longitudinal insight.

To investigate the symptoms of SARS-CoV-2 infection, their dynamics and their discriminatory power for the disease using longitudinally, prospectively collected information reported at the time of their occurrence. We have analysed data from a large phase 3 clinical UK COVID-19 vaccine trial. The alpha variant was the predominant strain. Participants were assessed for SARS-CoV-2 infection via nasal/throat PCR at recruitment, vaccination appointments, and when symptomatic. Statistical techniques were implemented to infer estimates representative of the UK population, accounting for multiple symptomatic episodes associated with one individual. An optimal diagnostic model for SARS-CoV-2 infection was derived. The 4-month prevalence of SARS-CoV-2 was 2.1%; increasing to 19.4% (16.0%-22.7%) in participants reporting loss of appetite and 31.9% (27.1%-36.8%) in those with anosmia/ageusia. The model identified anosmia and/or ageusia, fever, congestion, and cough to be significantly associated with SARS-CoV-2 infection. Symptoms' dynamics were vastly different in the two groups; after a slow start peaking later and lasting longer in PCR+ participants, whilst exhibiting a consistent decline in PCR- participants, with, on average, fewer than 3 days of symptoms reported. Anosmia/ageusia peaked late in confirmed SARS-CoV-2 infection (day 12), indicating a low discrimination power for early disease diagnosis.

Role of the NO-GC/cGMP signaling pathway in platelet biomechanics.

Cyclic guanosine monophosphate (cGMP) is a second messenger produced by the NO-sensitive guanylyl cyclase (NO-GC). The NO-GC/cGMP pathway in platelets has been extensively studied. However, its role in regulating the biomechanical properties of platelets has not yet been addressed and remains unknown. We therefore investigated the stiffness of living platelets after treatment with the NO-GC stimulator riociguat or the NO-GC activator cinaciguat using scanning ion conductance microscopy (SICM). Stimulation of human and murine platelets with cGMP-modulating drugs decreased cellular stiffness and downregulated P-selectin, a marker for platelet activation. We also quantified changes in platelet shape using deep learning-based platelet morphometry, finding that platelets become more circular upon treatment with cGMP-modulating drugs. To test for clinical applicability of NO-GC stimulators in the context of increased thrombogenicity risk, we investigated the effect of riociguat on platelets from human immunodeficiency virus (HIV)-positive patients taking abacavir sulfate (ABC)-containing regimens. Our results corroborate a functional role of the NO-GC/cGMP pathway in platelet biomechanics, indicating that biomechanical properties such as stiffness or shape could be used as novel biomarkers in clinical research.

Increased platelet activation and development of thrombosis has been linked to a dysfunctional NO-GC/cGMP signaling pathway. How this pathway affects platelet stiffness, however, has not been studied yet. For the first time, we used novel microscopy techniques to investigate stiffness and shape of platelets in human and murine blood samples treated with cGMP modifying drugs. Stiffness contains information about biomechanical properties of the cytoskeleton, and shape quantifies the spreading behavior of platelets. We showed that the NO-GC/cGMP signaling pathway affects platelet stiffness, shape, and activation in human and murine blood. HIV-positive patients are often treated with medication that may disrupt the NO-GC/cGMP signaling pathway, leading to increased cardiovascular risk. We showed that treatment with cGMP-modifying drugs altered platelet shape and aggregation in blood from HIV-negative volunteers but not from HIV-positive patients treated with medication. Our study suggests that platelet stiffness and shape can be biomarkers for estimating cardiovascular risk.

Infectious Proctitis due to Human Mpox.

We describe 2 cases of infectious proctitis secondary to human monkeypox in patients presenting with rectal pain. These cases highlight the importance of multidisciplinary management of monkeypox and in expanding case definitions and enabling clinical recognition in patients presenting without skin rash.

Safety and Efficacy of the NVX-CoV2373 Coronavirus Disease 2019 Vaccine at Completion of the Placebo-Controlled Phase of a Randomized Controlled Trial.

BACKGROUND: The recombinant protein-based vaccine, NVX-CoV2373, demonstrated 89.7% efficacy against coronavirus disease 2019 (COVID-19) in a phase 3, randomized, observer-blinded, placebo-controlled trial in the United Kingdom. The protocol was amended to include a blinded crossover. Data to the end of the placebo-controlled phase are reported. METHODS: Adults aged 18-84 years received 2 doses of NVX-CoV2373 or placebo (1:1) and were monitored for virologically confirmed mild, moderate, or severe COVID-19 (onset from 7 days after second vaccination). Participants who developed immunoglobulin G (IgG) against nucleocapsid protein but did not show symptomatic COVID-19 were considered asymptomatic. Secondary outcomes included anti-spike (S) IgG responses, wild-type virus neutralization, and T-cell responses. RESULTS: Of 15 185 participants, 13 989 remained in the per-protocol efficacy population (6989 NVX-CoV2373, 7000 placebo). At a maximum of 7.5 months (median, 4.5) postvaccination, there were 24 cases of COVID-19 among NVX-CoV2373 recipients and 134 cases among placebo recipients, a vaccine efficacy of 82.7% (95% confidence interval [CI], 73.3%-88.8%). Vaccine efficacy was 100% (95% CI, 17.9%-100.0%) against severe disease and 76.3% (95% CI, 57.4%-86.8%) against asymptomatic disease. High anti-S and neutralization responses to vaccination were evident, together with S-protein-specific induction of interferon-γ secretion in peripheral blood T cells. Incidence of serious adverse events and adverse events of special interest were similar between groups. CONCLUSIONS: A 2-dose regimen of NVX-CoV2373 conferred a high level of ongoing protection against asymptomatic, symptomatic, and severe COVID-19 through >6 months postvaccination. A gradual decrease of protection suggests that a booster may be indicated. CLINICAL TRIALS REGISTRATION: EudraCT, 2020-004123-16.

Influence of UGT1A1 and SLC22A6 polymorphisms on the population pharmacokinetics and pharmacodynamics of raltegravir in HIV-infected adults: a NEAT001/ANRS143 sub-study.

Using concentration-time data from the NEAT001/ARNS143 study (single sample at week 4 and 24), we determined raltegravir pharmacokinetic parameters using nonlinear mixed effects modelling (NONMEM v.7.3; 602 samples from 349 patients) and investigated the influence of demographics and SNPs (SLC22A6 and UGT1A1) on raltegravir pharmacokinetics and pharmacodynamics. Demographics and SNPs did not influence raltegravir pharmacokinetics and no significant pharmacokinetic/pharmacodynamic relationships were observed. At week 96, UGT1A1*28/*28 was associated with lower virological failure (p = 0.012), even after adjusting for baseline CD4 count (p = 0.048), but not when adjusted for baseline HIV-1 viral load (p = 0.082) or both (p = 0.089). This is the first study to our knowledge to assess the influence of SNPs on raltegravir pharmacodynamics. The lack of a pharmacokinetic/pharmacodynamic relationship is potentially an artefact of raltegravir's characteristic high inter and intra-patient variability and also suggesting single time point sampling schedules are inadequate to thoroughly assess the influence of SNPs on raltegravir pharmacokinetics.

Anticholinergic medications associated with falls and frailty in people with HIV.

BACKGROUND: Anticholinergic medications (ACMs) are associated with poorer age-related outcomes, including falls and frailty. We investigate associations between ACM use and recurrent falls and frailty among older (aged ≥50 years) people with HIV in the POPPY study. METHODS: Anticholinergic potential of co-medications at study entry was coded using the anticholinergic burden score, anticholinergic risk score, and Scottish Intercollegiate Guidelines Network score; drugs scoring ≥1 on any scale were defined as ACM. Associations with recurrent falls (two or more falls in the previous 28 days) and frailty (modified Fried's) were assessed using logistic regression adjusting for (1) possible demographic/lifestyle confounders and (2) clinical factors and depressive symptoms (Patient Health Questionnaire-9). RESULTS: ACM use was reported by 193 (28%) of 699 participants, with 64 (9%) receiving two or more ACM; commonly prescribed ACMs were codeine (12%), citalopram (12%), loperamide (9%), and amitriptyline (7%). Falls were reported in 63/673 (9%), and 126/609 (21%) met the frailty criteria. Both recurrent falls and frailty were more common in ACM users than in non-users (recurrent falls: 17% in users vs. 6% in non-users, p < 0.001; frailty: 32% vs. 17%, respectively, p < 0.001). Use of two or more ACMs was associated with increased odds of falls after adjustment for demographic/lifestyle factors (odds ratio [OR] 4.53; 95% confidence interval [CI] 2.06-9.98) and for clinical factors (OR 3.58; 95% CI 1.37-9.38). Similar albeit weaker associations were seen with frailty (OR 2.26; 95% CI 1.09-4.70 and OR 2.12; 95% CI 0.89-5.0, respectively). CONCLUSIONS: ACM are commonly prescribed for people living with HIV, and evidence exists for an association with recurrent falls and frailty. Clinicians should be alert to this and reduce ACM exposure where possible.

Strengths and Challenges of Various Models of Geriatric Consultation for Older Adults Living With Human Immunodeficiency Virus.

As care of persons living with human immunodeficiency virus (HIV; PWH) has transitioned from management of opportunistic infections to management of conditions associated with older age, new models of geriatric consultation are needed. The authors, who represent 9 clinics across North America and the United Kingdom, provided their insights on models of geriatric consultation for older PWH. Three models of geriatric consultation are delineated: outpatient referral/consultation, combined HIV/geriatric multidisciplinary clinic, and dually trained providers within 1 clinical setting. A patient-centered approach and the use of expertise across disciplines were universally identified as strengths. Logistical barriers and the reluctance of older PWH to see a geriatric care provider were identified as barriers to implementing these models. Although the optimal model of geriatric consultation depends on a region's resources, there is value in augmenting the training of infectious disease providers to include principles of geriatric care.

Population Pharmacokinetic Model and Alternative Dosing Regimens for Dolutegravir Coadministered with Rifampicin.

Dolutegravir-based regimens are recommended as first-line therapy for HIV in low- and middle-income countries where tuberculosis is the most common opportunistic infection. Concurrent HIV/tuberculosis treatment is challenging because of drug-drug interactions. Our analysis aimed to characterize dolutegravir's population pharmacokinetics when coadministered with rifampicin and assess alternative dolutegravir dosing regimens. We developed a population pharmacokinetic model of dolutegravir in NONMEM with data from two healthy-volunteer studies (RADIO and ClinicalTrials.gov identifier NCT01231542) and validated it with data from the INSPIRING study, which consisted of participants living with HIV. The model was developed with 817 dolutegravir plasma concentrations from 41 participants. A 2-compartment model with first-order elimination and lagged absorption best described dolutegravir's pharmacokinetics. For a typical 70-kg individual, we estimated a clearance, absorption rate constant, central volume, and peripheral volume of 1.03 L/h, 1.61 h-1, 12.7 L, and 3.85 L, respectively. Rifampicin coadministration increased dolutegravir clearance by 144% (95% confidence interval [CI], 126 to 161%). Simulations showed that when 50 or 100 mg once-daily dolutegravir is coadministered with rifampicin in 70-kg individuals, 71.7% and 91.5% attain trough concentrations above 0.064 mg/L, the protein-adjusted 90% inhibitory concentration (PA-IC90), respectively. The model developed from healthy-volunteer data describes patient data reasonably well but underpredicts trough concentrations. Although 50 mg of dolutegravir given twice daily achieves target concentrations in more than 99% of individuals cotreated with rifampicin, 100 mg of dolutegravir, once daily, in the same population is predicted to achieve satisfactory pharmacokinetic target attainment. The efficacy of this regimen should be investigated since it presents an opportunity for treatment simplification.

UK guideline for the use of HIV post-exposure prophylaxis 2021.

We present the updated British Association for Sexual Health and HIV (BASHH) guidelines for post-exposure prophylaxis (PEP) to HIV following sexual exposures, occupational exposures and other nonoccupational exposures in the community. This serves as an update to the 2015 BASHH guideline on PEP following sexual exposures and the 2008 Expert Advisory Group on AIDS guidelines on HIV PEP. We aim to provide evidence-based guidance on best clinical practice in the provision, monitoring and support of PEP for the prevention of HIV acquisition following sexual, occupational and other nonoccupational exposures in the community. The guideline covers when to prescribe PEP, what antiretroviral agents to use and how to manage PEP. This includes (i) evidence of PEP efficacy; (ii) evidence relating to individual-level efficacy of antiretroviral therapy to prevent the sexual transmission of HIV; (iii) data on the detectable (transmissible) prevalence of HIV in specific populations; (iv) risk of HIV transmission following different types of sexual and occupational exposure; (v) baseline risk assessment; (vi) drug regimens and dosing schedules; (vii) monitoring PEP; (viii) baseline and follow-up blood-borne virus testing; (ix) the role of PEP within broader HIV prevention strategies, for example, HIV pre-exposure prophylaxis (PrEP). The guideline also covers special scenarios such as PEP in pregnancy, breastfeeding and chronic hepatitis B virus infection, and when PEP should be considered in people using HIV PrEP. The guidelines are aimed at clinical professionals directly involved in PEP provision and other stakeholders in the field. A proforma to assist PEP consultations is included. A public consultation process was undertaken prior to finalizing the recommendations.

HIV Antivirals Affect Endothelial Activation and Endothelial-Platelet Crosstalk.

RATIONALE: People living with HIV on effective antiretroviral therapy are at increased risk of cardiovascular complications, possibly due to off-target drug effects. Some studies have associated antiretroviral therapy with increased risk of myocardial infarction and endothelial dysfunction, but a link between endothelial function and antiretrovirals has not been established. OBJECTIVE: To determine the effects of antiretrovirals in common clinical use upon in vitro endothelial function to better understand cardiovascular risk in people living with HIV. METHODS AND RESULTS: Human umbilical cord vein endothelial cells or human coronary artery endothelial cells were pretreated with the antiretrovirals abacavir sulphate (ABC), tenofovir disoproxil fumarate, or tenofovir alafenamide. Expression of adhesion molecules, ectonucleotidases (CD39 and CD73), tissue factor (TF), endothelial-derived microparticle (EMP) numbers and phenotype, and platelet activation were evaluated by flow cytometry. TF and ectonucleotidase activities were measured using colourimetric plate-based assays. ABC-treated endothelial cells had higher levels of ICAM (intercellular adhesion molecule)-1 and TF expression following TNF (tumor necrosis factor)-α stimulation. In contrast, tenofovir disoproxil fumarate and tenofovir alafenamide treatment gave rise to greater populations of CD39+CD73+ cells. These cell surface differences were also observed within EMP repertoires. ABC-treated cells and EMP had greater TF activity, while tenofovir disoproxil fumarate- and tenofovir alafenamide-treated cells and EMP displayed higher ectonucleotidase activity. Finally, EMP isolated from ABC-treated cells enhanced collagen-evoked platelet integrin activation and α-granule release. CONCLUSIONS: We report differential effects of antiretrovirals used in the treatment of HIV upon endothelial function. ABC treatment led to an inflammatory, prothrombotic endothelial phenotype that promoted platelet activation. In contrast, tenofovir disoproxil fumarate and tenofovir alafenamide conferred potentially cardioprotective properties associated with ectonucleotidase activity. These observations establish a link between antiretrovirals and specific functional effects that provide insight into cardiovascular disease in people living with HIV.

Factors associated with overweight/obesity in a cohort of people living with HIV over 50 years of age.

Changes in body weight in people living with HIV vary by regimen components, timing of therapy introduction (naive, switch) and demographic factors. Our objective was to evaluate weight change and factors associated in an ageing cohort of treated subjects with HIV at Chelsea and Westminster Hospital. We found that the prevalence of obesity was similar to general population and was associated with a number of health conditions, which increase metabolic risk.

Pharmacokinetic/pharmacodynamic investigation of raltegravir with or without lamivudine in the context of HIV-1 pre-exposure prophylaxis (PrEP).

BACKGROUND: To characterize their potential use in pre-exposure prophylaxis (PrEP) we compared the pharmacokinetics of raltegravir and lamivudine in genital tissue against ex vivo tissue infection with HIV-1. METHODS: Open-label trial of 36 HIV-negative females and males randomized to 7 days raltegravir 400 mg twice daily and 7 days raltegravir 400 mg+lamivudine 150 mg twice daily (after washout), or vice versa. Blood, saliva, rectal fluid, rectal tissue, vaginal fluid and vaginal tissue were sampled at baseline and on and off PrEP during a total of 12 days, for pharmacokinetics and antiviral activity via ex vivo HIV-1BaL challenge. Ex vivo infectivity was compared with baseline. The trial has been registered in https://clinicaltrials.gov/ with the identifier NCT03205566. RESULTS: Steady state for both drugs was reached by day 4. Dosing with raltegravir alone provided modest ex vivo HIV protection with higher drug levels in rectal tissue and vaginal tissue than in plasma on and off PrEP. Off PrEP, plasma and vaginal concentrations declined rapidly, while persisting in the rectum. On PrEP, the highest lamivudine concentrations were in the rectum, followed by vaginal tissue then plasma. Lamivudine washout was rapid in plasma, while persisting in the rectum and vagina. Raltegravir/lamivudine increased ex vivo protection on and off PrEP compared with raltegravir alone, reaching maximum protection at day 2 in rectal tissue and at day 8 in vaginal tissue. CONCLUSIONS: Raltegravir 400 mg+lamivudine 150 mg showed high levels of ex vivo HIV protection, associated with high drug concentrations persisting after discontinuation in vaginal and rectal compartments, supporting further investigation of these agents for PrEP.

The benefits of tenofovir discontinuation with or without bisphosphonate therapy in osteoporotic people living with HIV.

OBJECTIVES: Treatment with bisphosphonates and discontinuation of tenofovir disoproxil fumarate (TDF) are recommended strategies for managing osteoporosis in people living with HIV (PLHIV). This study aimed to compare the effects on bone mineral density (BMD) of TDF discontinuation with and without bisphosphonate therapy in osteoporotic PLHIV. METHODS: The present study is a retrospective cohort analysis of dual-energy X-ray absorptiometry scan results of PLHIV attending Chelsea and Westminster Hospital HIV clinic between 2009 and 2020. Osteoporotic (T-score < -2.5) patients with ≥ 6 months' TDF exposure were included. Changes in BMD and T-scores at the lumbar spine (LS) and femoral neck (FN) were assessed. RESULTS: A total of 84 participants were included, of whom 43 discontinued TDF only (TS) and 41 switched from TDF and received bisphosphonates (TS+): 86.9% were male; 77.4% were white; median (interquartile range, IQR) age was 54.8 (51.0-58.5) years; and median (IQR) TDF exposure was 6.5 (3.5-10.4) years. At a median follow-up of 2 years after TDF-discontinuation, mean spine BMD increased significantly in both groups, but bisphosphonate recipients had greater improvements (4.83% vs. 7.79%; P < 0.019); LS T-scores improved significantly but changes were comparable between groups (TS, 0.5 vs. TS+, 0.6; P = 0.270). At the FN, no significant increases in BMD were observed (TS, 3.05% vs. TS+, 2.71%; P = 0.205); T-scores significantly improved in bisphosphonate recipients only (+0.2; P = 0.003). A greater proportion recovered from osteoporosis in the TS+ group (34.9% vs. 43.9%), although differences between groups were not significant (P = 0.503). CONCLUSIONS: Our real-world data indicate that although TDF discontinuation significantly improved bone health in osteoporotic PLHIV, combining bisphosphonates with TDF discontinuation resulted in greater improvements in BMD.

Dose prediction for repurposing nitazoxanide in SARS-CoV-2 treatment or chemoprophylaxis.

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been declared a global pandemic and urgent treatment and prevention strategies are needed. Nitazoxanide, an anthelmintic drug, has been shown to exhibit in vitro activity against SARS-CoV-2. The present study used physiologically based pharmacokinetic (PBPK) modelling to inform optimal doses of nitazoxanide capable of maintaining plasma and lung tizoxanide exposures above the reported SARS-CoV-2 EC90 . METHODS: A whole-body PBPK model was validated against available pharmacokinetic data for healthy individuals receiving single and multiple doses between 500 and 4000 mg with and without food. The validated model was used to predict doses expected to maintain tizoxanide plasma and lung concentrations above the EC90 in >90% of the simulated population. PopDes was used to estimate an optimal sparse sampling strategy for future clinical trials. RESULTS: The PBPK model was successfully validated against the reported human pharmacokinetics. The model predicted optimal doses of 1200 mg QID, 1600 mg TID and 2900 mg BID in the fasted state and 700 mg QID, 900 mg TID and 1400 mg BID when given with food. For BID regimens an optimal sparse sampling strategy of 0.25, 1, 3 and 12 hours post dose was estimated. CONCLUSION: The PBPK model predicted tizoxanide concentrations within doses of nitazoxanide already given to humans previously. The reported dosing strategies provide a rational basis for design of clinical trials with nitazoxanide for the treatment or prevention of SARS-CoV-2 infection. A concordant higher dose of nitazoxanide is now planned for investigation in the seamless phase I/IIa AGILE trial.