Switch to bictegravir/emtricitabine/tenofovir alafenamide from dolutegravir-based therapy

OBJECTIVE

To evaluate the efficacy and safety of 96 weeks of bictegravir/emtricitabine/tenofovir alafenamide (B/F/TAF) treatment in participants switching from dolutegravir (DTG)-based therapy.

DESIGN

Studies 1489 (NCT02607930) and 1490 (NCT02607956) were phase 3 randomized, double-blind, active-controlled, first-line therapy trials in people with HIV-1. After 144 weeks of DTG-based or B/F/TAF treatment, participants could enter a 96-week open-label extension (OLE) of B/F/TAF.

METHODS

A pooled analysis evaluated viral suppression (HIV-1 RNA <50 copies/ml) and changes in CD4 + cell count at OLE Weeks 48 and 96, treatment-emergent resistance, safety, and tolerability after switch from a DTG-based regimen to B/F/TAF. Outcomes by prior treatment were summarized using descriptive statistics and compared by two-sided Wilcoxon rank sum test.

RESULTS

At OLE Week 96, participants who switched to B/F/TAF ( N  = 519) maintained high levels of virologic suppression (99.5 and 99.1% in those switching from DTG/abacavir/lamivudine and DTG+F/TAF, respectively) and CD4 + cell count, with no treatment-emergent resistance to B/F/TAF. Twenty-one participants experienced drug-related adverse events after switching, with diarrhea, weight gain, and headache occurring most commonly. There were no cases of proximal renal tubulopathy, drug-related Grade 4 adverse events, or serious adverse events. Two participants discontinued B/F/TAF due to treatment-related adverse events. Participants who switched from DTG/abacavir/lamivudine experienced statistically significant greater weight gain than those who switched from DTG+F/TAF; however, median weight change from the blinded phase baseline to OLE Week 96 was numerically similar across treatment groups.

CONCLUSION

This medium-term analysis demonstrates the safety and efficacy of switching to B/F/TAF from a DTG-containing regimen in people with HIV-1.

Attosecond and nano-Coulomb electron bunches via the Zero Vector Potential mechanism

The commissioning of multi-petawatt class laser facilities around the world is gathering pace. One of the primary motivations for these investments is the acceleration of high-quality, low-emittance electron bunches. Here we explore the interaction of a high-intensity femtosecond laser pulse with a mass-limited dense target to produce MeV attosecond electron bunches in transmission and confirm with three-dimensional simulation that such bunches have low emittance and nano-Coulomb charge. We then perform a large parameter scan from non-relativistic laser intensities to the laser-QED regime and from the critical plasma density to beyond solid density to demonstrate that the electron bunch energies and the laser pulse energy absorption into the plasma can be quantitatively described via the Zero Vector Potential mechanism. These results have wide-ranging implications for future particle accelerator science and associated technologies.

CAnceR IN PreGnancy (CARING) - a retrospective study of cancer diagnosed during pregnancy in the United Kingdom

BACKGROUND

The incidence of cancer diagnosed during pregnancy is increasing. Data relating to investigation and management, as well as maternal and foetal outcomes is lacking in a United Kingdom (UK) population.

METHODS

In this retrospective study we report data from 119 patients diagnosed with cancer during pregnancy from 14 cancer centres in the UK across a five-year period (2016-2020).

RESULTS

Median age at diagnosis was 33 years, with breast, skin and haematological the most common primary sites. The majority of cases were new diagnoses (109 patients, 91.6%). Most patients were treated with radical intent (96 patients, 80.7%), however, gastrointestinal cancers were associated with a high rate of palliative intent treatment (63.6%). Intervention was commenced during pregnancy in 68 (57.1%) patients; 44 (37%) had surgery and 31 (26.1%) received chemotherapy. Live births occurred in 98 (81.7%) of the cases, with 54 (55.1%) of these delivered by caesarean section. Maternal mortality during the study period was 20.2%.

CONCLUSIONS

This is the first pan-tumour report of diagnosis, management and outcomes of cancer diagnosed during pregnancy in the UK. Our findings demonstrate proof of concept that data collection is feasible and highlight the need for further research in this cohort of patients.

A treadmill exercise reduced cardiac fibrosis, inflammation and vulnerability to ischemia-reperfusion in rat pristane-induced arthritis

AIMS

To explore cardiac structural and functional parameters and myocardial sensitivity to ischemia in a rat model of chronic arthritis, pristane-induced arthritis (PIA), and to investigate the effects of a running exercise protocol on cardiac disorders related to rheumatoid arthritis (RA).

MAIN METHODS

3 groups of male Dark Agouti rats were formed: Controls, PIA and PIA-Exercise. The PIA-Exercise group was subjected to an individualized treadmill running protocol during the remission phase. At acute and chronic phases of PIA, cardiac structure was analyzed by histology. Cardiac function was explored in isolated hearts to measure left ventricular developed pressure (LVDP), cardiac compliance and infarct size before and after ischemia/reperfusion. Cardiac inflammation was evaluated through VCAM-1 mRNA expression by RT-qPCR. Plasma irisin levels were measured by ELISA.

KEY FINDINGS

PIA rats exhibited myocardial hypertrophy fibrosis and inflammation at the 2 inflammatory phases of the model. At chronic phase only, LVDP and cardiac compliance were lower in PIA compared to controls. As compared to sedentary PIA, exercise did not change cardiac function but reduced fibrosis, inflammation, infarct size, and arthritis severity and increased irisin levels. Cardiac inflammation positively correlated with fibrosis, while irisin levels negatively correlated with cardiac inflammation and fibrosis.

SIGNIFICANCE

In the PIA model that recapitulated most cardiac disorders of RA, a daily program of treadmill running alleviated cardiac fibrosis and inflammation and improved resistance to ischemia. These data provide arguments to promote the practice of exercise in RA patients for cardiac diseases prevention.

Predation risk drives long-term shifts in migratory behaviour and demography in a large herbivore population

Migration is an adaptive life-history strategy across taxa that helps individuals maximise fitness by obtaining forage and avoiding predation risk. The mechanisms driving migratory changes are poorly understood, and links between migratory behaviour, space use, and demographic consequences are rare. Here, we use a nearly 20-year record of individual-based monitoring of a large herbivore, elk (Cervus canadensis) to test hypotheses for changing patterns of migration in and adjacent to a large protected area in Banff National Park (BNP), Canada. We test whether bottom-up (forage quality) or top-down (predation risk) factors explained trends in (i) the proportion of individuals using 5 different migratory tactics, (ii) differences in survival rates of migratory tactics during migration and whilst on summer ranges, (iii) cause-specific mortality by wolves and grizzly bears, and (iv) population abundance. We found dramatic shifts in migration consistent with behavioural plasticity in individual choice of annual migratory routes. Shifts were inconsistent with exposure to the bottom-up benefits of migration. Instead, exposure to landscape gradients in predation risk caused by exploitation outside the protected area drove migratory shifts. Carnivore exploitation outside the protected area led to higher survival rates for female elk remaining resident or migrating outside the protected area. Cause-specific mortality aligned with exposure to predation risk along migratory routes and summer ranges. Wolf predation risk was higher on migratory routes than summer ranges of montane-migrant tactics, but wolf predation risk traded-off with heightened risk from grizzly bears on summer ranges. A novel eastern migrant tactic emerged following a large forest fire that enhanced forage in an area with lower predation risk outside of the protected area. The changes in migratory behaviour translated to population abundance, where abundance of the montane-migratory tactics declined over time. The presence of diverse migratory life histories maintained a higher total population abundance than would have been the case with only one migratory tactic in the population. Our study demonstrates the complex ways in which migratory populations change over time through behavioural plasticity and associated demographic consequences because of individuals balancing predation risk and forage trade-offs.

Reporting of paediatric osteoporotic vertebral fractures in Duchenne muscular dystrophy and potential impact on clinical management: the need for standardised and structured reporting

BACKGROUND

In boys with Duchenne muscular dystrophy (DMD), initiation of bisphosphonate is recommended upon identification of moderate or severe vertebral fractures, even if asymptomatic. Clear radiological reporting is important for consistency of clinical interpretation and management.

OBJECTIVES

To audit radiology reports of spine imaging for vertebral fracture assessment in DMD, and assess potential impact on diagnosis and management.

MATERIALS AND METHODS

Lateral thoracolumbar spine imaging (71 lateral spine radiographs and 13 lateral dual energy absorptiometry spine image) in 84 boys with DMD performed across two centres. Anonymised radiology reports by paediatric radiologists were circulated to two neuromuscular clinicians and two endocrinologists. Clinicians determined if there was vertebral fracture, no vertebral fracture, or unclear interpretation. Endocrinologists also determined if bisphosphonate was indicated. A single observer (a clinician with expertise in vertebral fracture assessment) performed vertebral fracture assessment in 37 images and re-reported using a structured format. Structured reports were re-circulated to the four clinicians to re-evaluate the degree of concordance in clinical diagnosis of vertebral fracture and treatment decisions with bisphosphonate.

RESULTS

The term "fracture" was used in 25/84 (30%) radiology reports and only in 8/43 (19%) with description of vertebral body abnormalities. Fracture grading was included in 7/43 (16%) radiology reports. Diagnostic concordance by the clinicians was noted in 36/84 (43%). Unclear interpretation was noted in 22% to 51% based on radiology reports. No unclear interpretation was noted with structured reports. Complete diagnostic (37/37, 100%) and treatment (37/37, 100%) concordance was noted with the structured reports, whereas complete diagnostic and treatment concordance was noted in only 16/37 (43%) and 17/37 (46%) of the radiology reports, respectively.

CONCLUSION

Only a third of radiology reports of spine imaging in DMD explicitly used the terminology "fracture". Grading was only noted in a small percentage. Variability in diagnostic interpretation by clinicians may lead to differing management plans. As identification of vertebral fracture is a trigger for treatment, developing reporting guidelines for paediatric vertebral fracture assessment will improve care. A structured template should be introduced for radiological reporting of paediatric vertebral fracture assessment.

Bictegravir, emtricitabine, and tenofovir alafenamide versus dolutegravir, emtricitabine, and tenofovir disoproxil fumarate for initial treatment of HIV-1 and hepatitis B coinfection (ALLIANCE): a double-blind, multicentre, randomised controlled, phase 3 non-inferiority trial

BACKGROUND

For most adults with HIV-1 and hepatitis B virus (HBV) coinfection, initial recommended treatment is a tenofovir-containing antiretroviral regimen, but no randomised studies have compared tenofovir disoproxil fumarate with tenofovir alafenamide. We aimed to investigate whether bictegravir, emtricitabine, and tenofovir alafenamide is non-inferior to dolutegravir, emtricitabine, and tenofovir disoproxil fumarate for viral suppression in individuals with HIV-1 and HBV coinfection at 48 and 96 weeks.

METHODS

We did this randomised, double-blind, active-controlled, phase 3, non-inferiority trial at 46 outpatient centres in China, Dominican Republic, Hong Kong, Japan, Malaysia, South Korea, Spain, Taiwan, Thailand, Turkey, and the USA. Eligible participants were treatment-naive adults (aged ≥18 years) with plasma HIV-1 RNA of at least 500 copies per mL and plasma HBV DNA of at least 2000 IU/mL. Participants were randomly assigned (1:1) to receive daily oral bictegravir 50 mg, emtricitabine 200 mg, and tenofovir alafenamide 25 mg, or dolutegravir 50 mg, emtricitabine 200 mg, and tenofovir disoproxil fumarate 300 mg, each with corresponding matching placebo. Randomisation was stratified by hepatitis B e antigen (HBeAg) status (positive vs negative), HBV DNA (<8 vs ≥8 log10 IU/mL), and CD4 count (<50 vs ≥50 cells per μL) at screening. All investigators, participants, and staff providing treatment, assessing outcomes, and collecting data were masked to study treatment for 96 weeks. Coprimary endpoints were the proportion of participants with plasma HIV-1 RNA less than 50 copies per mL (defined by the US Food and Drug Administration snapshot algorithm) and plasma HBV DNA less than 29 IU/mL (using the missing-equals-failure approach) at week 48, with a prespecified non-inferiority margin of -12%. Coprimary endpoints were assessed in the full analysis set, which included all randomly assigned participants who received at least one dose of study drug and had at least one post-baseline HIV-1 RNA or HBV DNA result while on study drug. Safety endpoints were assessed in all randomly assigned participants who received at least one dose of study drug. This trial is registered with ClinicalTrials.gov, NCT03547908.

FINDINGS

Between May 30, 2018 and March 16, 2021, 381 participants were screened, of whom 243 initiated treatment (121 in the receive bictegravir, emtricitabine, and tenofovir alafenamide group; 122 in the dolutegravir, emtricitabine, and tenofovir disoproxil fumarate group). At week 48, both endpoints met the criteria for non-inferiority: 113 (95%) of 119 participants in the bictegravir, emtricitabine, and tenofovir alafenamide group and 111 (91%) of 122 participants in the dolutegravir, emtricitabine, and tenofovir disoproxil fumarate group had HIV-1 RNA less than 50 copies per mL (difference 4·1, 95% CI -2·5 to 10·8; p=0·21), and 75 (63%) of 119 participants in the bictegravir, emtricitabine, and tenofovir alafenamide group versus 53 (43%) of 122 participants in the dolutegravir, emtricitabine, and tenofovir disoproxil fumarate group had HBV DNA suppression (difference 16·6, 5·9 to 27·3; nominal p=0·0023). Drug-related adverse events up to week 96 occurred in 35 (29%) of 121 participants in the bictegravir, emtricitabine, and tenofovir alafenamide group and 34 (28%) of 122 participants in the dolutegravir, emtricitabine, and tenofovir disoproxil fumarate group. One (1%) of 121 participants in the bictegravir, emtricitabine, and tenofovir alafenamide group reported a serious adverse event (cryptococcal meningitis attributed to immune reconstitution inflammatory syndrome) that was deemed to be treatment-related.

INTERPRETATION

Coformulated bictegravir, emtricitabine, and tenofovir alafenamide is an effective therapy for adults with HIV-1 and HBV coinfection starting antiviral therapy.

FUNDING

Gilead Sciences.

Standardization of radiograph readings during bowel management week

INTRODUCTION

During "bowel management week," abdominal radiographs are used to monitor the amount and location of stool. A radiologist familiar with the treatment plan can provide an improved interpretation. The goal of this paper is to standardize the radiological reports during a bowel management week.

METHODS

We saw 744 patients during bowel management week from May 2016 until March 2023. Diagnosis included: anorectal malformation (397), idiopathic constipation (180), Hirschsprung disease (89), and spina bifida (78). Laxatives were the treatment for 51% of patients, and 49% received enemas. Characteristic radiographs were selected for each treatment group for a proposed reading standardization.

RESULTS

When the stool is visualized, it is crucial to report its location. Having a contrast enema helps with the correct interpretation of the colonic anatomy. It is also essential to always compare the amount of stool with the radiograph from the previous day to determine if there is an increase or decrease in stool. Examples of radiographs are shown to guide the use of the preferred proposed terminology.

CONCLUSION

Providing information regarding which treatment modality the patient is receiving and stating that a patient is on a bowel management week treatment is crucial for the radiologist to provide adequate interpretation. The radiologist must be familiar with the treatment goals and purpose of the daily radiograph.

Bictegravir/emtricitabine/tenofovir alafenamide as initial treatment for HIV-1: five-year follow-up from two randomized trials

Background

Bictegravir/emtricitabine/tenofovir alafenamide (B/F/TAF) is a single-tablet regimen recommended for HIV-1 treatment. The safety and efficacy of B/F/TAF as initial therapy was established in two Phase 3 studies: 1489 (vs dolutegravir [DTG]/abacavir/lamivudine) and 1490 (vs DTG + F/TAF). After 144 weeks of randomized follow-up, an open-label extension evaluated B/F/TAF to 240 weeks.

Methods

Of 634 participants randomized to B/F/TAF, 519 completed the double-blinded treatment, and 506/634 (80%) chose the 96-week open-label B/F/TAF extension, which was completed by 444/506 (88%) participants. Efficacy was based on the secondary outcome of the proportion of participants with HIV-1 RNA <50 copies/mL at Week 240 by missing = excluded and missing = failure methods. All 634 participants who were randomized to B/F/TAF and received at least one dose of B/F/TAF were included in efficacy and safety analyses. (Study 1489: ClinicalTrials.govNCT02607930; EudraCT 2015-004024-54. Study 1490: ClinicalTrials.govNCT02607956; EudraCT 2015-003988-10).

Findings

Of those with available virologic data, 98.6% (95% CI [97.0%-99.5%], 426/432) maintained HIV-1 RNA <50 copies/mL at Week 240 (missing = excluded); when missing virologic data were considered as failure, 67.2% (95% CI [63.4%-70.8%], 426/634) maintained HIV-1 RNA <50 copies/mL. Mean (SD) change in CD4+ count from baseline was +338 (236.2) cells/μL. No treatment-emergent resistance to B/F/TAF was detected. Adverse events led to drug discontinuation in 1.6% (n = 10/634) of participants (n = 5 with events considered drug-related). No discontinuations were due to renal adverse events. Median (IQR) total cholesterol increased 21 (1,42) mg/dL from baseline; the change in total cholesterol:HDL was 0.1 (-0.5,0.6). Median (IQR) weight change from baseline was +6.1 kg (2.0, 11.7) at Week 240. In Study 1489, hip and spine bone mineral density mean percent changes from baseline were ≤0.6%.

Interpretation

Through 5 years of follow-up, B/F/TAF maintained high rates of virologic suppression with no treatment-emergent resistance and rare drug discontinuations due to adverse events. These results demonstrate the durability and safety of B/F/TAF in people with HIV.

Funding

Gilead Sciences.

Efficacy and safety of switching to bictegravir, emtricitabine, and tenofovir alafenamide in virologically suppressed Asian adults living with HIV: A pooled analysis from three international phase III randomized trials

OBJECTIVES

Data on switching to bictegravir, emtricitabine, and tenofovir alafenamide (B/F/TAF) in virologically suppressed Asian people living with HIV are limited. We performed a pooled analysis of virologically suppressed Asian participants from three international phase III trials to evaluate the efficacy and safety of switching to B/F/TAF.

METHODS

Virologically suppressed people living with HIV were randomized to switch to B/F/TAF or to stay on baseline regimens. The primary endpoint was the proportion of participants with plasma HIV-1 RNA ≥50 copies/ml at week 48. We analysed the incidence of adverse events (AEs), laboratory abnormalities, and changes in relevant tolerability parameters through 48 weeks.

RESULTS

Overall, 136 Asian participants were included. The proportions of participants with plasma HIV-1 RNA ≥50 copies/ml at week 48 were low in both arms (0% for B/F/TAF vs 1.4% for those who stayed on baseline regimens). Those who switched to B/F/TAF had virological suppression rates similar to those who stayed on baseline regimens (100% vs 95.9%, p = 0.2485), with no treatment-emergent resistance. Drug-related AEs occurred in three participants in each arm; none were serious. No participants discontinued the study drug because of AEs, and no deaths were observed. No significant differences were observed between the arms in the median changes in estimated glomerular filtration rate, body weight, and most lipid parameters. Switching from tenofovir disoproxil fumarate-containing regimens to B/F/TAF resulted in a significant decrease in tubular proteinuria compared with those who stayed on baseline regimens (p < 0.01).

CONCLUSIONS

Virologically suppressed Asian people living with HIV who switched to B/F/TAF maintained 100% virological suppression at week 48, with no treatment-emergent drug resistance and safety profiles comparable to those seen in people who stayed on baseline regimens.

CLINICAL TRIAL NUMBER

ClinicalTrials.gov (NCT02603120, NCT02652624, and NCT02603107).

Bictegravir/emtricitabine/tenofovir alafenamide in older individuals with HIV: Results of a 96-week, phase 3b, open-label, switch trial in virologically suppressed people ≥65 years of age

OBJECTIVES

Bictegravir/emtricitabine/tenofovir alafenamide (B/F/TAF) is an effective treatment for HIV-1 infection; however, clinical trial data in older people living with HIV (PLWH) are lacking. The primary 24-week and secondary 48-week analyses of study GS-US-380-4449 (NCT03405935), which assessed the efficacy and safety of switching to B/F/TAF in older PLWH, have been published. Here we report the results of the final 96-week analyses from the study.

METHODS

In this 96-week, phase 3b, open-label, single-arm trial, virologically suppressed PLWH aged ≥65 years switched from elvitegravir/cobicistat/emtricitabine/tenofovir alafenamide or a tenofovir disoproxil fumarate-based regimen to B/F/TAF. Viral suppression, resistance, immune response, safety, tolerability and adherence were evaluated through week 96.

RESULTS

Of 90 participants screened, 86 were enrolled and switched to B/F/TAF. No participants had HIV-1 RNA ≥50 copies/ml (by FDA Snapshot algorithm) at weeks 72 or 96; virologic suppression rates were 94.2% (81/86; 95% CI 87.0-98.1) and 74.4% (64/86; 95% CI 63.9-83.2), respectively. No treatment-emergent resistance was observed, and CD4 counts remained stable. There were no study drug-related serious adverse events. Three participants experienced drug-related treatment-emergent adverse events that led to premature drug discontinuation. There were no clinically relevant changes from baseline to week 96 in fasting lipid parameters, and the median change in body weight at week 96 was 0.0 kg (IQR -2.3, 2.0). Median self-reported adherence was 100% (IQR 100-100%).

CONCLUSIONS

Switching to B/F/TAF is an effective long-term option for virologically suppressed adults ≥65 years of age, with favourable safety and tolerability profiles in this population.

1251. 5-year outcomes of bictegravir/emtricitabine/tenofovir alafenamide (B/F/TAF) as initial treatment of HIV-1 in adults with high baseline HIV-1 RNA and/or low CD4 count in two Phase 3 randomized clinical trials

Background

People with HIV (PWH) who are initiated on guidelines-recommended first-line INSTI-based antiretroviral therapy routinely achieve rapid virologic suppression; however, those with a high baseline (BL) HIV-1 RNA and/or low CD4 count may be more challenging to manage in the short- and long-term. To further characterize long-term outcomes over 5 years in select subgroups, we analyzed results from two studies examining B/F/TAF as initial treatment stratified by BL HIV-1 RNA and/or CD4 count.

Methods

Adults with HIV were randomized to receive blinded initial treatment with B/F/TAF versus dolutegravir [DTG]/abacavir/lamivudine (Study 1489) or DTG+F/TAF (1490) for 144 weeks (W) of blinded treatment followed by an optional switch to open-label B/F/TAF for 96W. We present virologic response (HIV-1 RNA < 50 c/mL, missing=excluded and missing=failure) and study drug-related adverse events (DRAE) from a pooled analysis of participants originally randomized to B/F/TAF who had BL HIV-1 RNA 100,00-400,000 copies(c)/mL, HIV-1 RNA >400,000 c/mL and/or CD4 count < 200 cells/µL through W240.

Results

634 adults (median age 32 years, 89% men, 33% Black/African descent, 24% Hispanic/LatinX) originally randomized to B/F/TAF were included for analysis. At BL, 80 participants had a BL CD4 count < 200 cells/µL and 119 participants had HIV-1 RNA >100,000 c/mL, of whom, 20 had HIV-1 RNA >400,000 c/mL. At W240, virologic suppression was high for the low CD4 count and/or high HIV-1 RNA subgroups (Table). No participant in the final resistance analysis developed virologic resistance to any component of B/F/TAF. Across the subgroups, the most common DRAEs were nausea, headache and diarrhea and there were no serious DRAEs. There was only one discontinuation due to a DRAE in the low CD4 count subgroup, and none in the high HIV-1 RNA subgroup.

Conclusion

Initial treatment with B/F/TAF was safe and efficacious over 5 years of follow-up in people with a high BL HIV-1 RNA and/or low CD4 count. These outcomes provide additional evidence that B/F/TAF is an effective and durable regimen for a broad range of PWH, including those with advanced disease.

Disclosures

Moti Ramgopal, MD, FACP, FIDSA, Gilead Sciences: Advisor/Consultant|Gilead Sciences: Speakers Bureau|Janssen: Advisor/Consultant|Janssen: Speakers Bureau|Merck: Advisor/Consultant|Merck: Speakers Bureau|ViiV: Advisor/Consultant|ViiV: Speakers Bureau Axel Baumgarten, MD, AbbVie: Honoraria|Gilead Sciences: Honoraria|Janssen: Honoraria|MSD: Honoraria|ViiV: Honoraria Anton Pozniak, MD, FRCP, Gilead: Grant/Research Support|Gilead: Honoraria|Janssen: Grant/Research Support|Janssen: Honoraria|Merck: Honoraria|theratec: Honoraria|ViiV: Grant/Research Support|ViiV: Honoraria Chloe Orkin, MBChB, FRCP, MD, Gilead Sciences: Honoraria|GSK: Honoraria|Janssen: Honoraria|MSD: Honoraria Juan Manuel Tiraboschi, PhD, Gilead Sciences: Advisor/Consultant|Gilead Sciences: Grant/Research Support|Janssen: Advisor/Consultant|Janssen: Grant/Research Support|MSD: Advisor/Consultant|MSD: Grant/Research Support|ViiV Healthcare: Advisor/Consultant|ViiV Healthcare: Grant/Research Support Debbie P. Hagins, MD, FAPCR, AAHIVS, Gilead Sciences: Advisor/Consultant|Gilead Sciences: Grant/Research Support|Gilead Sciences: Speakers Bureau|Janssen: Grant/Research Support|Merck: Advisor/Consultant|Merck: Grant/Research Support|ViiV: Advisor/Consultant|ViiV: Grant/Research Support Hailin Huang, PhD, Gilead Sciences, Inc.: Employer|Gilead Sciences, Inc.: Stocks/Bonds Kristin Andreatta, MSc, Gilead Sciences, Inc: Employee of Gilead Sciences|Gilead Sciences, Inc: Stocks/Bonds Nathan Unger, PharmD, AAHIVP, Gilead Sciences: Employee|Gilead Sciences: Stocks/Bonds Jason Hindman, PharmD, MBA, Gilead Sciences: Employee|Gilead Sciences: Stocks/Bonds Hal Martin, MD, Gilead Sciences: employee|Gilead Sciences: Stocks/Bonds Jared Baeten, MD, PhD, Gilead Sciences: Employee|Gilead Sciences: Stocks/Bonds Olayemi Osiyemi, MD, Gilead: Advisor/Consultant|gsk: Advisor/Consultant|viiv: Advisor/Consultant.

POS0418 ICE CRYOTHERAPY: A NEW STRATEGY TO REDUCE ARTERIAL INFLAMMATION IN RHEUMATOID ARTHRITIS? A STUDY IN ADJUVANT-INDUCED ARTHRITIS MODEL

Background

Rheumatoid arthritis (RA) is characterized by endothelial activation (EA), endothelial dysfunction and vascular inflammation, leading to accelerated atherosclerosis. In the last decade, a renewed interest in cryotherapy - local or whole body - has emerged. Although growing evidence demonstrated that ice cryotherapy reduces not only pain but also disease progression, whether such therapy might blunt disorders of the systemic vasculature is unknown.

Objectives

The aim of our study was to determine the effects of a subchronic treatment with ice cryotherapy on aortic leucocyte infiltration and markers of endothelial activation in the rat adjuvant-induced arthritis (AIA) model.

Methods

AIA was induced by injection of Mycobacterium butyricum in Freund’s incomplete adjuvant at the base of the tail in 6-week-old male Lewis rats. AIA rats were treated or not with ice applied on paws, from the onset of arthritis to the acute inflammatory stage of the disease, twice a day for 14 days. Arthritis score and paw skin temperature were daily monitored. At the end of the treatment, leucocyte infiltration and the different cell subsets (monocytes/macrophages, neutrophils, CD4+ and CD8+ T cells producing or not IL-17A) were measured in thoracic aorta using flow cytometry. Relative mRNA expression of cytokines/chemokines (IL-6, TNF-α, CXCL-1, MIP-1α (CCL-3), MCP-1 (CCL-2)) and adhesion molecules (ICAM-1, VCAM-1) was analyzed in thoracic aorta by RT-qPCR. X-Ray analysis of hind paws was performed to assign a radiographic score.

Results

Treatment with ice cryotherapy, that decreased skin surface temperature from 28.6 ± 0.3°C to 18.5 ± 0.2°C, reduced arthritis score (-36%, p<0.001) and radiographic score (-34%, p<0.05) with a positive effect on osteoporosis, cartilage and bone destruction. These effects were associated with a dramatic decrease in CD4+, CD8+ and Tc17 cell aortic infiltration as compared to untreated AIA. By contrast, ice had no effect on endothelial activation markers except VCAM-1 mRNA expression that was significantly increased (p<0.05). A positive correlation was found between the number of total leucocytes, monocytes/macrophages, CD4+ and CD8+ T cells in aorta and arthritis score.

Conclusion

In the model of AIA that reproduces arterial wall inflammation recently characterized in rheumatoid arthritis by PET/CT [1], local ice cryotherapy exerts not only local beneficial effects on the joints but also systemic benefits on vascular inflammation in large vessels. These results suggest that reduction of vascular comorbidities might be a new output of ice cryotherapy used as an adjunctive therapy in RA.

References

[1]Agca et al. Rheumatology (Oxford) (2021)

Disclosure of Interests

None declared.

Effects of local cryotherapy on systemic endothelial activation, dysfunction, and vascular inflammation in adjuvant-induced arthritis (AIA) rats

Aim

This study explored the systemic vascular effects of local cryotherapy with a focus on endothelial changes and arterial inflammation in the model of rat adjuvant-induced arthritis (AIA).

Methods

Cryotherapy was applied twice a day on hind paws of AIA rats from the onset of arthritis to the acute inflammatory phase. Endothelial activation was studied in the aorta by measuring the mRNA levels of chemokines (CXCL-1, MCP-1 (CCL-2), MIP-1α (CCL-3)) and adhesion molecules (ICAM-1, VCAM-1) by qRT-PCR. Endothelial dysfunction was measured in isolated aortic and mesenteric rings. Aortic inflammation was evaluated via the mRNA expression of pro-inflammatory cytokines (TNF-α, IL-6) by qRT-PCR and leucocyte infiltration analysis (flow cytometry). Plasma levels of TNF-α, IL-6, IL-1β, IL-17A, and osteoprotegerin (OPG) were measured using Multiplex/ELISA.

Results

AIA was associated with an increased aortic expression of CXCL-1 and ICAM-1 as well as an infiltration of leucocytes and increased mRNA expression of IL-6, IL-1β, and TNF-α. Local cryotherapy, which decreased arthritis score and structural damages, reduced aortic mRNA expression of CXCL-1, IL-6, IL-1β, and TNF-α, as well as aortic infiltration of leucocytes (T lymphocytes, monocytes/macrophages, neutrophils) and improved acetylcholine-induced vasorelaxation in the aorta and mesenteric arteries. Plasma levels of IL-17A and OPG were significantly reduced by cryotherapy, while the number of circulating leucocytes was not. IL-17A levels positively correlated with endothelial activation and dysfunction.

Conclusion

In the AIA model, local cryotherapy reduced systemic endothelial activation, immune cell infiltration, and endothelial dysfunction. Mechanistically, the reduction of circulating levels of IL-17A appears as the possible link between joint cooling and the remote vascular effects.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13075-022-02774-1.

Brief Report: Bictegravir/Emtricitabine/Tenofovir Alafenamide Efficacy in Participants With Preexisting Primary Integrase Inhibitor Resistance Through 48 Weeks of Phase 3 Clinical Trials

BACKGROUND

Preexisting drug resistance limits the utility of HIV antiretroviral therapy. Studies have demonstrated safety and efficacy of bictegravir/emtricitabine/tenofovir alafenamide (B/F/TAF), including in patients with M184V/I substitutions.

SETTING

We investigated virologic outcomes through 48 weeks of B/F/TAF treatment in individuals with preexisting primary integrase strand transfer inhibitor resistance (INSTI-R).

METHODS

Preexisting INSTI-R was retrospectively evaluated from 7 B/F/TAF studies. INSTI-R was assessed by historical genotypes and/or baseline RNA or DNA sequencing. Viral loads were measured at all visits.

RESULTS

Preexisting primary INSTI-R substitutions were detected in 20 of the 1907 participants (1.0%). The 20 participants were predominantly male (75%), were Black (65%), had HIV-1 subtype B (85%), and had baseline median CD4 counts of 594 cells/mm3 and median age of 52 years. Most of the participants (n = 19) were virologically suppressed at baseline and had one primary INSTI-R substitution, E92G, Y143C/H, S147G, Q148H/K/R, N155S, or R263K, +/-secondary substitutions. All suppressed participants maintained virologic suppression throughout 48 weeks without any viral blips. One treatment-naive participant had virus with Q148H+G140S that was fully sensitive to bictegravir but only partially to dolutegravir (phenotype <2.5-fold change and >4-fold change, respectively). With a baseline viral load of 30,000 copies/mL, this participant was virologically suppressed by week 4 and maintained <50 copies/mL through week 48.

CONCLUSIONS

This small cohort with primary INSTI-R achieved and/or maintained virologic suppression through 48 weeks of B/F/TAF treatment. Consistent with the potent in vitro activity of bictegravir against most INSTI-R patterns, B/F/TAF may be a potential treatment option for patients with select preexisting INSTI-R, if confirmed by further studies.

69. Incidence of metabolic complications among treatment-naïve adults living with HIV-1 randomized to B/F/TAF, DTG/ABC/3TC or DTG+F/TAF after 144 Weeks

Background

Metabolic comorbidities including diabetes (DM) and dyslipidemia pose challenges to the long-term care of people with HIV (PWH). Incidence of cardiovascular disease and DM are reported at higher rates in PWH than the general population. Obesity is broadly prevalent in both the general population and PWH, and higher body mass index (BMI) can contribute to metabolic complications. Here we present longer-term follow up on incidence of DM, hypertension (HTN), BMI categorical shifts, and lipid changes over 144 weeks of blinded treatment from two trials of PWH initiating antiretroviral therapy.

Methods

We assessed incidence of metabolic complications in adult PWH in Study 1489: bictegravir/emtricitabine/tenofovir alafenamide (B/F/TAF) vs dolutegravir/abacavir/ lamivudine (DTG/ABC/3TC) and Study 1490: B/F/TAF vs DTG+F/TAF. Treatment-emergent (TE) metabolic comorbidities were defined by standard MedDRA search lists. CDC-defined BMI categories were compared from baseline (BL) to Week 144. Analyses by sex at birth and race were performed, as well as for lipid changes.

Results

Among 1,274 total participants, median (range) age was 33 years (18-77), 90% men, 33% black. In study 1489, BL prevalence of DM and HTN was 4.5 and 12.1% with TE DM and HTN in B/F/TAF being 0.7% and 10%, and for DTG/ABC/3TC 1.3% and 6.9%, respectively. In study 1490, BL prevalence of DM and HTN was 6.8 and 18.8% with TE DM and HTN in B/F/TAF being 2.1 and 5.8%, and for DTG+F/TAF 2.3 and 6.5%, respectively. BMI shift from Normal to Obese: B/F/TAF 0%, DTG/ABC/3TC 3.2%, p=0.12 (1489) (Table 1); B/F/TAF 2.5%, DTG+F/TAF 2.9% p=1.00 (1490) (Table 2). Subgroup analyses by gender/race showed similar findings for TE DM, HTN, and BMI changes. Median changes from BL fasted lipids were small (Table 1).

Table 1§. Studies 1489 and 1490: Metabolic Outcomes from Baseline to Week 144

Table 2±. Shift Table of BMI Category at Week 144 by Baseline BMI Category – Overall

Conclusion

Through over 144 weeks of follow up, PWH randomized to initiate B/F/TAF, DTG/ABC/3TC or DTG+F/TAF had low rates of incident DM or HTN-related AEs, with no statistically significant differences by treatment group. BMI changes/categorical shifts from BL did not significantly differ by regimen, and no clinically significant change or difference by regimen in lipids were observed. While data are limited by three years of follow up, they are strengthened by randomized study design of three widely used initial ART regimens.

Disclosures

Eric Daar, MD, Bristol-Myers Squibb (Consultant)Gilead Sciences Inc. (Consultant, Scientific Research Study Investigator, Advisor or Review Panel member, Research Grant or Support)Janssen (Consultant, Advisor or Review Panel member, Research Grant or Support)Merck (Consultant, Advisor or Review Panel member, Research Grant or Support)Teva (Consultant, Advisor or Review Panel member)ViiV Healthcare (Consultant, Advisor or Review Panel member, Research Grant or Support) Chloe Orkin, MD, Gilead Sciences Inc. (Grant/Research Support, Scientific Research Study Investigator, Other Financial or Material Support)Janssen (Research Grant or Support, Other Financial or Material Support)Merck (Research Grant or Support, Other Financial or Material Support)ViiV Healthcare (Research Grant or Support, Other Financial or Material Support) Paul Sax, MD, Gilead Sciences (Consultant, Grant/Research Support)Janssen (Consultant)Merck (Consultant, Research Grant or Support)ViiV (Consultant, Research Grant or Support) Jeffrey L. Stephens, MD, Gilead Sciences Inc. (Scientific Research Study Investigator, Research Grant or Support) Ellen Koenig, MD, Gilead Sciences Inc. (Scientific Research Study Investigator) Amanda Clarke, MD, Gilead Sciences Inc. (Consultant, Scientific Research Study Investigator, Other Financial or Material Support, Conference attendance sponsorship)ViiV Healthcare (Consultant, Other Financial or Material Support, Conference travel sponsorship) Axel Baumgarten, MD, AbbVie (Advisor or Review Panel member, Speaker’s Bureau)Bristol-Myers Squibb (Advisor or Review Panel member, Speaker's Bureau)Gilead Sciences Inc. (Scientific Research Study Investigator, Advisor or Review Panel member, Speaker's Bureau)Janssen (Speaker’s Bureau)Merck (Advisor or Review Panel member) Cynthia Brinson, MD, Abbvie (Scientific Research Study Investigator)BI (Scientific Research Study Investigator)Gilead Sciences Inc. (Scientific Research Study Investigator, Advisor or Review Panel member, Speaker's Bureau, Personal fees)GSK (Scientific Research Study Investigator)Novo Nordisk (Scientific Research Study Investigator)ViiV Healthcare (Scientific Research Study Investigator, Advisor or Review Panel member, Speaker's Bureau) Moti Ramgopal, MD FIDSA, Abbvie (Scientific Research Study Investigator, Speaker's Bureau)Gilead (Consultant, Scientific Research Study Investigator, Speaker's Bureau)Janssen (Consultant, Scientific Research Study Investigator, Research Grant or Support, Speaker's Bureau)Merck (Consultant, Scientific Research Study Investigator)ViiV (Consultant, Scientific Research Study Investigator, Speaker's Bureau) Hailin Huang, PhD, Gilead Sciences Inc. (Employee, Shareholder) Terry Farrow, MD, Gilead Sciences Inc. (Employee, Shareholder) Jared Baeten, MD, PHD, Gilead Sciences Inc. (Employee, Shareholder) Jason Hindman, PharmD, Gilead Sciences Inc. (Employee, Shareholder) Hal Martin, MD, MPH, Gilead Sciences Inc. (Employee, Shareholder) Kimberly Workowski, MD, Nothing to disclose

Switching to Bictegravir/Emtricitabine/Tenofovir Alafenamide in Black Americans With HIV-1: A Randomized Phase 3b, Multicenter, Open-Label Study

BACKGROUND

With the highest rates of HIV/AIDS in the United States, Black Americans are still underrepresented in HIV medical research.

SETTING

BRAAVE (NCT03631732) is a randomized, phase 3b, multicenter, open-label US study.

METHODS

Adults identifying as Black or African American and virologically suppressed on 2 nucleoside reverse transcriptase inhibitors (NRTIs) plus third agent were randomized (2:1) to switch to open-label bictegravir/emtricitabine/tenofovir alafenamide (B/F/TAF) once daily or stay on baseline regimen (SBR) for 24 weeks, after which SBR had delayed switch to B/F/TAF. Resistance to non-NRTIs, protease inhibitors, and/or NRTIs was permitted; integrase strand transfer inhibitor resistance was exclusionary. Primary endpoint was proportion of participants with HIV-1 RNA ≥50 copies/mL at week 24 (snapshot algorithm; noninferiority margin of 6%).

RESULTS

Of 558 screened, 495 were randomized/treated (B/F/TAF n = 330; SBR n = 165). Overall, 32% were ciswomen, 2% transwomen, and 10% had an M184V/I mutation. At week 24, 0.6% on B/F/TAF vs 1.8% on SBR had HIV-1 RNA ≥50 copies/mL (difference -1.2%; 95% confidence interval -4.8% to 0.9%), demonstrating noninferiority of B/F/TAF vs SBR. Proportions with HIV-1 RNA <50 copies/mL at week 24 were 96% B/F/TAF and 95% SBR and remained high at week 48. No participant had treatment-emergent resistance to study drug. Treatments were well tolerated. Study drug-related adverse events, mostly grade 1, occurred in 10% of participants on B/F/TAF through week 48 and led to discontinuation in 9 participants through week 48.

CONCLUSIONS

For Black Americans with HIV, switching to B/F/TAF was noninferior to continuing a variety of regimens, including those with pre-existing NRTI mutations.

Three-year study of pre-existing drug resistance substitutions and efficacy of bictegravir/emtricitabine/tenofovir alafenamide in HIV-1 treatment-naive participants

OBJECTIVES

Two Phase 3, randomized, double-blind, active-controlled studies of initial HIV-1 treatment demonstrated that bictegravir/emtricitabine/tenofovir alafenamide (B/F/TAF) was non-inferior to dolutegravir/abacavir/lamivudine (DTG/ABC/3TC; Study 1489) or to DTG+F/TAF (Study 1490) through 144 weeks. In both studies, there was no emergent resistance to study drugs. Here, the 3 year resistance analysis and impact of baseline resistance substitutions on treatment response are described.

METHODS

Population sequencing of HIV-1 protease and reverse transcriptase (RT) was performed at screening. Retrospective baseline next generation sequencing of protease, RT and integrase (IN) was analysed at a ≥ 15% cutoff. Resistance analyses were performed on participants with confirmed viral rebound of HIV-1 RNA ≥200 copies/mL through Week 144 or last visit who did not resuppress to <50 copies/mL while on study drug.

RESULTS

Transmitted primary drug resistance substitutions were present in the following proportions of participants: integrase strand transfer inhibitor (INSTI) resistance (-R) in 1.3% (17/1270) of participants; NRTI-R in 2.7% (35/1274); NNRTI-R in 14.1% (179/1274); and PI-R in 3.5% (44/1274). These pre-existing resistance substitutions not associated with study drug did not affect treatment outcomes. One participant in the B/F/TAF group had pre-existing bictegravir and dolutegravir resistance substitutions (Q148H+G140S in integrase) at baseline and suppressed and maintained HIV-1 RNA <50 copies/mL through Week 144. In total, 21 participants qualified for resistance testing [1.3% (8/634) B/F/TAF; 1.9% (6/315) DTG/ABC/3TC; 2.2% (7/325) DTG+F/TAF]; none had emergent resistance to study drugs.

CONCLUSIONS

Treatment with B/F/TAF, DTG/ABC/3TC, or DTG+F/TAF achieved high, durable rates of virological suppression in HIV-1 treatment-naive participants. The presence of pre-existing resistance substitutions did not affect treatment outcomes, and there was no treatment-emergent resistance.

Switching to Bictegravir, Emtricitabine, and Tenofovir Alafenamide in Virologically Suppressed Adults With Human Immunodeficiency Virus

Background

Bictegravir (B)/emtricitabine (F)/tenofovir alafenamide (TAF) is guideline-recommended treatment for human immunodeficiency virus type 1 (HIV-1). We evaluated whether people receiving dolutegravir (DTG) plus F/TAF or F/TDF (tenofovir disoproxil fumarate) with viral suppression can switch to B/F/TAF without compromising safety or efficacy, regardless of preexisting nucleoside reverse transcriptase inhibitor (NRTI) resistance.

Methods

In this multicenter, randomized, double-blinded, active-controlled, noninferiority trial, we enrolled adults who were virologically suppressed for ≥6 months before screening (with documented/suspected NRTI resistance) or ≥3 months before screening (with no documented/suspected NRTI resistance) on DTG plus either F/TDF or F/TAF. We randomly assigned (1:1) participants to switch to B/F/TAF or DTG + F/TAF once daily for 48 weeks, each with matching placebo. The primary endpoint was proportion of participants with plasma HIV-1 RNA ≥50 copies/mL at week 48 (snapshot algorithm); the prespecified noninferiority margin was 4%.

Results

Five hundred sixty-seven adults were randomized; 565 were treated (284 B/F/TAF, 281 DTG + F/TAF). At week 48, B/F/TAF was noninferior to DTG + F/TAF, as 0.4% (1/284) vs 1.1% (3/281) had HIV-1 RNA ≥50 copies/mL (difference, −0.7% [95.001% confidence interval {CI}, −2.8% to 1.0%]). There were no significant differences in efficacy among participants with suspected or confirmed prior NRTI resistance (n = 138). No participant had treatment-emergent drug resistance. Median weight change from baseline at week 48 was +1.3 kg (B/F/TAF) vs +1.1 kg (DTG + F/TAF) (P = .46). Weight change differed by baseline NRTIs (+2.2 kg [F/TDF] and +0.6 kg [F/TAF], P < .001), with no differences between B/F/TAF and DTG + F/TAF.

Conclusions

The single-tablet regimen B/F/TAF is a safe, effective option for people virologically suppressed on DTG plus either F/TDF or F/TAF, including in individuals with preexisting resistance to NRTIs.

Clinical Trials Registration

NCT03110380.

Fixed-dose combination bictegravir, emtricitabine, and tenofovir alafenamide in adolescents and children with HIV: week 48 results of a single-arm, open-label, multicentre, phase 2/3 trial

BACKGROUND

Bictegravir is a potent integrase strand-transfer inhibitor (INSTI) with a high genetic barrier to resistance. Bictegravir, coformulated with emtricitabine and tenofovir alafenamide, is recommended by key European and US HIV treatment guidelines as the preferred single-tablet regimen for adults and adolescents. The aim of this study was to assess the pharmacokinetics, safety, and efficacy of switching to this regimen in virologically suppressed children and adolescents with HIV.

METHODS

In this single-arm, open-label trial, we enrolled virologically suppressed children and adolescents (aged 6 to <18 years) with HIV at 22 hospital clinics in South Africa, Thailand, Uganda, and the USA. Eligible participants had a bodyweight of at least 25 kg, were virologically suppressed (HIV-1 RNA <50 copies per mL) on a stable ART regimen for at least 6 months before screening, had a CD4 count of at least 200 cells per μL, and an estimated glomerular filtration rate of at least 90 mL/min per 1·73 m² by the Schwartz formula at screening. All participants received the fixed-dose regimen of coformulated bictegravir 50 mg, emtricitabine 200 mg, and tenofovir alafenamide 25 mg once daily. Pharmacokinetic analysis was used for dosing confirmation, and results compared with adult values. The primary outcomes were area under the curve at the end of the dosing interval (AUC_tau) and concentration at the end of the dosing interval (C_tau) of bictegravir, and incidence of treatment-emergent adverse events and laboratory abnormalities at week 24. Efficacy and safety analyses included all participants who received at least one dose of study drug. We report the 48-week results. This study is registered with ClinicalTrials.gov, NCT02881320.

FINDINGS

Between Sept 29, 2016 and Feb 16, 2018, we enrolled 102 participants. 100 participants received bictegravir, emtricitabine, and tenofovir alafenamide (cohort 1 [adolescents aged 12 to <18 years], n=50; cohort 2 [children aged 6 to <12 years], n=50). The mean bictegravir AUC_tau was 89 100 ng × h/mL (coefficient of variation 31·0%) in adolescents (cohort 1) and 128 000 ng × h/mL (27·8%) in children (cohort 2). Compared with adults, bictegravir C_tau was 35% lower in adolescents and 11% lower in children. The 90% CIs of both parameters were within the predefined pharmacokinetic equivalence boundary and within overall range of exposures observed in adults and deemed to be safe and efficacious (geometric least-squares mean ratio [GLSM] 86·3% [90% CI 80·0-93·0] for AUC_tau and 65·4% [58·3-73·3] for C_tau in adolescents; GLSM 125% [90% CI 117-134] for AUC_tau and 88·9% [80·6-98·0] for C_tau for children). Bictegravir, emtricitabine, and tenofovir alafenamide was well tolerated; most adverse events were grade 2 or less in severity and no study drug-related serious adverse events were reported. One participant discontinued study drug due to adverse events (grade 2 insomnia and anxiety). Virological suppression (HIV-1 RNA <50 copies per mL) was maintained by all 100 participants at week 24 and by 98 (98%) of 100 at week 48; no participants had treatment-emergent resistance.

INTERPRETATION

In adolescents and children with HIV, the bictegravir, emtricitabine, and tenofovir alafenamide single-tablet regimen was well tolerated and maintained virological suppression. Our data support the treatment of HIV in adolescents and children with this single-tablet regimen. At present, the single-tablet regimen is recommended as first-line treatment in the USA for adolescents and as an alternative regimen in children and has the potential to represent an important regimen in the paediatric population.

FUNDING

Gilead Sciences.

AB0073 INTESTINAL PERMEABILITY IN SPONDYLOARTHRITIS: A SYSTEMATIC REVIEW OF THE LITERATURE

Background:

Growing evidence argue for a role of the gut in the pathophysiology of various chronic rheumatic diseases such as spondyloarthritis (SpA). This so-called “gut-joint axis” involves dysbiosis, bacterial translocation, intestinal inflammation and increase in intestinal permeability. Recent data from clinical and basic research suggested that the integrity of the intestinal barrier might be a key determinant in translating autoimmunity to inflammation, making intestinal permeability a potential marker or a target for future therapies.

Objectives:

To analyse the available data on intestinal permeability in SpA patients and the effects of drugs such as non-steroidal anti-inflammatory drugs (NSAIDs) on intestinal permeability.

Methods:

A systematic review was conducted. Without date restriction, the following databases were searched through September 1, 2020: Medline, Embase and Cochrane. Studies with patients with SpA assessing the intestinal permeability were selected. Some of the included studies have assessed the effect of NSAIDs on intestinal permeability.

Results:

A total of 12 studies were included in the final analysis. The 12 studies involved a total of 268 SpA patients, including 240 ankylosing spondylitis (AS). Among the studies included, four studies used the lactulose/mannitol test, four studies used the 51Cr-ethylenediaminetetraacetic test and two studies used the polyethylene glycols test. Nine of the 12 studies reported increased intestinal permeability regardless on the method used for intestinal permeability evaluation. Four studies evaluated the link between disease activity, assessed by CRP and ESR levels, and intestinal permeability and showed no correlation between increased intestinal permeability and markers of disease activity in AS patients. As regards the effects of NSAIDs on intestinal permeability, data are controversial. Two studies, including one evaluating indomethacin, did not show any influence of NSAIDs in AS patients, one study showed an increase in intestinal permeability under NSAIDs in only 60% of the patients, another study reported increased intestinal permeability. When comparing the effect of NSAIDs in patients with AS to healthy subjects, one study reported a comparable NSAIDs-induced increase in intestinal permeability in both groups.

Conclusion:

The results of our review suggest that increased intestinal permeability is present in SpA patients even in the absence of NSAIDs use and regardless of the method used to assess intestinal permeability. The effects of NSAIDs on intestinal permeability in SpA patients is more controversial and further studies are needed to clarify them.

Disclosure of Interests:

None declared

AB0062 TIME COURSE OF INTESTINAL PERMEABILITY AND BACTERIAL TRANSLOCATION IN THE MODEL OF ADJUVANT-INDUCED ARTHRITIS

Background:

Intestinal inflammation, dysbiosis, intestinal permeability (IP) and bacterial translocation (BT) have been identified in patients with spondyloarthritis but the time at which they appear and their contribution to the pathogenesis of the disease is still a matter of debate.

Objectives:

To investigate the time-course of intestinal inflammation, IP and BT in a rat model of reactive arthritis, a subgroup of SpA, the adjuvant-induced arthritis model.

Methods:

Adjuvant-induced arthritis (AIA) was induced in 6-week-old male Lewis rats by an injection at the base of the tail of Mycobacterium butyricum with incomplete Freund’s adjuvant (Day (D) 0). Control rats received saline using the same procedure. Body weights and a clinical arthritis score were daily assessed. A group of AIA and control rats (n=15 per group) were euthanized at three different times of arthritis: D4 for the pre-arthritic phase (AIA-preclinical), D11 for the onset of arthritis (AIA-onset) and D28 for the acute phase (AIA-acute). In each group (AIA and control, n=15 per group)), IP was assessed by measuring plasma levels of zonulin (ELISA) and ileal mRNA expression of zonulin and occludin (RT-qPCR), BT was studied by measuring bacterial endotoxins (or LPS, by LCMS2 method), soluble CD-14 (sCD14, ELISA) and ileal mRNA expression of TLR-4, and intestinal inflammation was assessed by measuring ileal mRNA expression of IL-8, IL-33, IL-17, IL-23p19 and TNF-α (RT-qPCR). Joint damage was assessed by the determination of a clinical and radiographic score of hind paws.

Results:

Body weights of AIA rats decreased from D4 to D28 as compared to controls, in parallel to the development of a severe clinical and radiographic arthritic disease from D11 and D28. Compared to control rats, AIA induced an increase in plasma zonulin levels at D4, D11 but not at D28. Ileal mRNA zonulin overexpression occurred at D11 while occludin was unchanged. As early as Day 4 (preclinical phase), mRNA of IL-8, IL-33 and IL-17 were overexpressed in ileum from AIA. At Day 11 (onset), overexpression of IL-8 persisted and mRNA of TNF-α and IL-23p19 increased in AIA. Neither LPS levels nor ileal mRNA expression of TLR-4 were changed by arthritis whatever the phase of arthritis. By contrast, blood levels of sCD-14 was significantly increased in the AIA group at all stages of arthritis. No correlation was found between clinical and radiographic arthritis scores and zonulin or LPS levels. Conversely, a negative correlation was observed between intestinal IL-8 mRNA expression and arthritis score (r=-0.3, p=0.02).

Conclusion:

In an animal model of SpA, intestinal inflammation and increased intestinal permeability occur prior to joint inflammation, suggesting a role of these disorders in the pathogenesis of this disease.

Acknowledgements:

I would like to thank the Société Française de Rhumatologie for its support in this work.

Disclosure of Interests:

None declared