SAFETY AND PHARMACOKINETICS OF IGPRO20 (SUBCUTANEOUS IMMUNOGLOBULIN) AND IGPRO10 (INTRAVENOUS IMMUNOGLOBULIN) IN ADULTS WITH SYSTEMIC SCLEROSIS (SSC) – RESULTS FROM A PHASE 2 TRIAL

BackgroundSystemic sclerosis (SSc) is a severe, progressive multisystem rheumatic disease with high mortality, but without approved disease-modifying treatment to stop or reverse course of disease. Intravenous immunoglobulin G (IgG) may have a positive impact on SSc based upon available literature reports. However, to date, there have been no clinical trials evaluating subcutaneous IgG (SCIG) in SSc. In particular, the impact of pathologically altered skin in SSc on local safety and pharmacokinetics (PK) of SCIG has not been explored yet.ObjectivesThe primary and secondary objectives of this trial (NCT04137224) included safety, including local infusion safety, and bioavailability of subcutaneous IgG (IgPro20) in adults with diffuse cutaneous SSc (dcSSc).MethodsThis was a randomized, open-label, crossover study. Adult subjects with dcSSc diagnosis within 5 years from first non-Raynaud's phenomenon and modified Rodnan Skin Score of 15-45 at screening were randomized 1:1 to sequence A (IgPro20, 20% normal human subcutaneous immunoglobulin followed by IgPro10, 10% normal human intravenous immunoglobulin) or sequence B (IgPro10 followed by IgPro20). Each subject was to complete two treatment periods (16 weeks each), with up to 40 weeks (including screening) study duration for an individual subject. Doses received were 0.5g/kg/week split over two sessions for IgPro20, and 2g/kg/4 weeks split over 2-5 days for IgPro10. The primary endpoint was safety of IgPro20, described as treatment-emergent adverse events (TEAEs) and changes in clinical observations.Results27 subjects were randomized, with 13 subjects to sequence A and 14 subjects to sequence B. In total, 25 subjects completed the study. Of 27 treated subjects, 107 TEAEs occurred in 22 subjects (81.5%) over the 36-week study period, the majority of which were mild or moderate. The most common TEAEs (>10% of subjects) by preferred term (PT) were headache (12 events occurring in 6 subjects [22.2%]), COVID-19 (3 events occurring in 3 subjects [11.1%]), diarrhoea (3 events occurring in 3 subjects [11.1%]), and vomiting (3 events occurring in 3 subjects [11.1%]).A total of 10 serious AEs (SAEs) were reported in 6 subjects (Viral infection, Chronic gastritis, Vomiting, Dehydration, Upper gastrointestinal haemorrhage, Chest pain, Myocardial infarction, Myocardial ischemia, Breast cancer, Interstitial lung disease). Among these, one subject experienced 2 SAEs (myocardial ischemia & myocardial infarction) and was discontinued from study treatment. None of the SAEs were considered related to study treatment by the investigator, and no deaths were reported.For IgPro20, 14 infusion site reactions (ISRs) occurred in 5 subjects (19.2%), all were mild or moderate in severity. The most common ISRs were infusion site pain and infusion site swelling (3 events in 2 subjects each, 7.7%). In total, 686 IgPro20 infusions were performed, resulting in an overall ISR rate per infusion of 0.02, ie 2 ISRs per 100 infusions. No ISRs were reported for IgPro10.No clinically relevant trends in vital signs, body weight, clinical laboratory tests, electrocardiograms, or pulmonary function tests were observed.PK profiles and bioavailability in dcSSc subjects were similar to those observed in other approved indications such as Primary Immunodeficiency. Population relative bioavailability of IgPro20, based on dose-normalized, baseline-corrected AUC0-tau was 0.761 (90% CI: 0.7033, 0.8232), ie 76.1% compared to IgPro10 (intravenous IgG).ConclusionThe overall safety profiles of IgPro20 and IgPro10 in subjects with dcSSc were consistent with that in approved indications such as CIDP, including a relatively low ISR rate for IgPro20. PK profiles and bioavailability were also similar to other indications. This study indicates that subcutaneous administration of IgPro20 has acceptable safety, bioavailability and PK profiles in patients with dcSSc. AcknowledgementsEditorial assistance was provided by Meridian HealthComms Ltd., funded by CSL Behring.Disclosure of InterestsChristopher P Denton Speakers bureau: Ja ssen, Boehringer Ingelheim, Consultant of: GSK, CSL Behring, Boehringer Ingelheim, Merck, Roche, Sanofi, Grant/research support from: GSK, CSL Behring, Inventiva, Horizon, Otylia Kowal-Bielecka Speakers bureau: Abbvie, Janssen-Cilag, Boehringer Ingelheim, Medac, MSD, Novartis, Pfizer, Sandoz, Consultant of: Boehringer Ingelheim and Novartis, Grant/research support from: Received congress support from Abbvie, Boehringer Ingelheim, and Medac, Susanna Proudman Speakers bureau: Boehringer Ingelheim, Grant/research support from: Janssen, Marzena Olesińska Consultant of: AstraZeneca, Margitta Worm Consultant of: Novartis Pharma GmbH, Sanofi-Aventis Deutschland GmbH, DBV Technologies S.A, Aimmune Therapeutics UK Limited, Regeneron Pharmaceuticals, Inc, Leo Pharma GmbH, Boehringer Ingelheim Pharma GmbH &Co.KG, ALK-Abelló Arzneimittel GmbH, Kymab Limited, Amgen GmbH, Abbvie Deutschland GmbH & Co. KG, Pfizer Pharma GmbH, Mylan Germany GmbH (A Viatris Company), AstraZeneca GmbH, Lilly Deutschland GmbH and GlaxoSmithKline GmbH & Co. KG., Nicoletta Del Papa Speakers bureau: Janssen Cilag, Boehringer Ingelheim., Marco Matucci-Cerinic Speakers bureau: Biogen, Sandoz, Boehringer Ingelheim, Consultant of: CSL Behring, Boehringer Ingelheim, Grant/research support from: MSD, Chemomab, Jana Radewonuk Shareholder of: CSL Behring, Employee of: CSL Behring, Jeanine Jochems Shareholder of: CSL Behring, Employee of: CSL Behring, Amgad Shebl Shareholder of: CSL Behring, Employee of: CSL Behring, Anna Krupa Shareholder of: CSL Behring, Employee of: CSL Behring, Jutta Hofmann Shareholder of: CSL Behring, Employee of: CSL Behring, Maria Gasior Shareholder of: CSL Behring, Employee of: CSL Behring.

IDDF2023-ABS-0299 Effectiveness of relink initiatives to re-engage diagnosed-but-untreated HCV-positive patients with direct-acting antiviral treatment

BackgroundHepatitis C virus (HCV) infection is a major cause of chronic liver disease that can progress to cirrhosis and hepatocellular carcinoma. The WHO has identified HCV infection as a public health threat and set a global target for HCV elimination by 2030. Simple pangenotypic direct-acting antiviral regimens allow most patients to be cured with minimal pretreatment and on-treatment monitoring. To achieve the WHO goal, patients including previously diagnosed HCV-positive patients who have been lost to follow-up, need to be linked to care. Studies report that up to 60% of patients who test positive for HCV antibodies are lost to follow-up and not treated. This loss has been further exacerbated by the COVID-19 pandemic, and many patients put off receiving care. Here, we explore the effectiveness of care re-engagement programs for patients with HCV.MethodsWe assessed ReLink programs (sponsored by Gilead Sciences, Inc.), designed to identify and re-engage HCV-positive patients with medical care and start/restart HCV treatment. We evaluated these programs by analyzing the number of patients, steps in the care cascade where patients were lost to follow-up, and the efficacy of the engagement program (determined by the number relinked and treated).ResultsSix programs assessed 44,964 patient records, identifying 11,163 patients lost to follow-up and eligible for contact. The main reason for the loss of follow-up was the inability to contact patients. Overall, 3726 patients were relinked with care, and 701 were treated. Several key points were identified for improving patient engagement with care, including the use of electronic databases to identify patients lost to follow-up, securing reliable contact information for patients, and partnership with medical societies.ConclusionsActive case finding, patient navigation, and care coordination in these programs led to increased engagement and treatment rates. Engaging HCV-positive patients with care is urgent, as many may already have developed more advanced liver disease. Adopting and adapting effective strategies from these programs may be a feasible way to improve patient outcomes and increase treatment numbers, thus contributing to meeting the WHO goal of HCV elimination.

Chronic Cavitary Pulmonary Histoplasmosis in an Immunocompetent Patient.

Histoplasma capsulatum is a fungal organism that causes systemic histoplasmosis. It is commonly asymptomatic in healthy immunocompetent individuals. The clinical symptoms of chronic cavitary histoplasmosis are typically seen in the immunodeficient population, particularly in smokers with pre-existing structural lung disease. We report a case of chronic cavitary histoplasmosis in an immunocompetent patient from an endemic area without pre-existing structural lung pathology. She presented complaining of right hypochondrial pain and had no history of respiratory symptoms nor history suggestive of immunosuppression, tuberculosis, or recent travel. CT scan revealed a cavitary lung lesion and a hilar mediastinal mass. Biopsies obtained by bronchoscopy revealed signs of necrosis, granulomas, and the presence of fungal organisms consistent with histoplasmosis. Histoplasma antibodies by complement fixation for yeast antibodies test were positive establishing the diagnosis of chronic cavitary pulmonary histoplasmosis (CCPH). She was then started on itraconazole with good tolerance. On follow-up three months later, a chest CT done along with measurement of inflammatory markers and liver enzymes demonstrated complete clinical recovery. This case emphasizes the importance of expanding our current understanding of the clinical presentation and manifestations of histoplasmosis beyond the conventional assumption that severe disease only affects immunocompromised individuals.

Longitudinal improvements in clinical and functional outcomes following initiation of elexacaftor/tezacaftor/ivacaftor in patients with cystic fibrosis

Background: The advent of highly effective modulator therapies (HEMTs), including elexacaftor/tezacaftor/ivacaftor (ELX/TEZ/IVA), for treatment of cystic fibrosis (CF) has resulted in remarkable clinical improvement for modulator-naive patients and for those who have been treated with prior modulator therapies. Intranasal micro-optical coherence tomography (muOCT) has detected functional abnormalities in the mucociliary apparatus of people with CF. The objectivewas to characterize the effects of ELX/TEZ/ IVA on nasal mucociliary clearance by muOCT and monitor the clinical changes conferred as a way to understand the effects. Method(s): Of 26 individuals aged 12 and older with at least one F508del mutation recruited, 24 were enrolled and followed over three visits: baseline and 1 (visit 2) and 6 months (visit 4) after initiation of ELX/TEZ/IVA therapy;the COVID-19 pandemic affected visit windows. Intranasal muOCT imaging was conducted at baseline and visit 2 as previously described;additional imaging for 18 months (visit 5) is in progress. Clinical outcomes, including percentage predicted forced expiratory volume in 1 second (FEV1pp) and sweat chloride levels were computed as part of the parent Prospective Study to Evaluate Biological and Clinical Effects of Significantly Corrected CFTR Function (PROMISE study). A blinded investigator team analyzed in vivo muOCT parameters including mucociliary transport (MCT) rate, ciliary beat frequency (CBF), and periciliary liquid depth (PCL) after devising an improved stabilization algorithm. Analysis of airway surface liquid (ASL) depthswas excluded because of the limited number of cases in which the necessary condition for measurement,which is preservation of a clear air layer between the mucus layer and the probe, was satisfied. Result(s): Twenty-three subjects completed visits 1 and 2, and 18 completed visits 1, 2, and 4. Average age at baselinewas 27 +/- 8.7, 69% were female, and 43% were on prior two-drug modulator therapy. No significant change in body mass index was found between the visits. FEV1pp increased significantly (10.9%, 95% CI, 76.1-98.4%) by visit 2 and persisted at visit 4 (10.6%, 95% CI, 87.7-107.0;p < 0.001). Sweat chloride levels decreased significantly at visit 2 (-36.6 mmol/L, 95% CI, 40.9-54.9 mmol/L) and visit 4 (-41.3 mmol/L, 95% CI, 34.9-51.8 mmol/L) at visit 4 ( p < 0.001). Analysis of muOCT images revealed significant improvement in MCT rate (2.8 +/- 1.5 mm/ min at baseline vs 4.0 +/- 1.5 mm/min at visit 2, p = 0.048), although no discernable changes were noted in CBF or PCL. When stratified based on use of prior modulator therapy, no significant differences were found for any muOCT metric. No significant correlations between change in MCT rates and change in FEV1pp or sweat chloride from baseline to visit 2were found. Conclusion(s): Treatment with ELX/TEZ/IVA in people with CF, including those that were treatment naive and those on prior modulator therapy, resulted in significant, sustained improvement in lung function and decreases in sweat chloride levels at ~10 months, consistent with recently published reports. Functional improvements in MCTratewere evident after initiation of ELX/TEZ/IVA therapy, which may partially explain the findings of better whole-lung mucus clearance and reduction in chronic infections reported previously. muOCT imaging in people with CF is sensitive to the treatment effect of HEMT and suggests better mucociliary transport as a mechanism of action underlying the clinical benefits for lung health. Acknowledgements: On behalf of the PROMISE investigatorsCopyright © 2022, European Cystic Fibrosis Society. All rights reserved

Cervical Cancer Prevention: The Role of the Nurse and Medical Care in Primary and Secondary Cancer Prevention

Objective: Although these days the priority is to fight the Covid-19 pandemic, the importance of human papillomavirus (HPV) infection is not to be neglected. Mechanism: Cervical cancer is caused mainly by a chronic infection with one or more of the high-risk subtypes of HPV -most commonly a sexually transmitted disease acquired early in life. Most HPV infections go away on their own, but some can lead to a precancerous state that, if left untreated, can undergo complete neoplastic transformation. Findings in Brief: There is a hope that in the future the combination of screening tests with vaccinations against oncogenic strains of HPV will allow reductions in the percentage of those contracting cervical cancer. Conclusion(s): The importance of educational activities should be emphasized in developmental gynecology in the context of oncological prevention. The roles of both doctors and nurses are important here. During the Covid-19 Pandemic, these kinds of activities are not to be abandoned. In addition, efforts should be made to develop more practical and workable HPV and cervical screening strategies for use during a pandemic.Copyright © 2022 The Author(s). Published by IMR Press.

Fc RECEPTOR-MEDIATED INFECTION OF MYELOID CELLS BY SARS-CoV-2

Background: The role of myeloid cells in the pathogenesis of SARS-CoV-2 is well established, in particular as drivers of cytokine production and systemic inflammation characteristic of severe COVID-19. However, the potential for myeloid cells to act as bona fide targets of productive SARS-CoV-2 infection remains unclear. Method(s): Using anti-SARS-CoV-2 mAbs with a range of neutralisation potencies and binding specificities, we performed a detailed assessment of mAb-mediated infection of monocytes/macrophages. THP-1 cells were used as a model system, with results confirmed in primary macrophages. Result(s): Infection of THP-1 cells was seen via mAbs targeting the spike RBD, but not with those targeting the NTD or S2 subunit. mAbs with the most consistent potential to mediate infection targeted a conserved region of the RBD (group 1/class IV). No infection was seen with the same quantity of virus but in the absence of antibody, and pre-treating the cells with FcgammaRI and -II blocking antibodies inhibited infection. Thus, antibody-FcR interactions are able to expand the tropism of SARS-CoV-2. Time-course studies demonstrated high-level and productive infection. Studies performed in human iPSC-derived macrophages and primary monocyte-derived macrophages paralleled results seen in THP-1 cells but with lower infection levels. Up to 2% of macrophages were infected, with infected cells appearing multinucleated and syncytial. Addition of ruxolitinib, an inhibitor of JAK1/2 signalling, increased infection up to 10-fold, indicating limitation of infection through innate immune mechanisms. Sera from primary infections (n=80) mediated rare infection events, with a minority of samples (n=3) promoting significant infection. Competition assays confirmed results seen in sera, with the addition of neutralising mAbs diminishing the infection seen with infection-mediating mAbs. Thus, the presence of antibodies with potential to mediate infection is not sufficient to predict myeloid cell infection, rather, the context in which the antibodies are produced is key. Conclusion(s): We hypothesise that a nascent antibody response during peak viral replication in primary infection presents a window of opportunity for myeloid cells to become infected, while establishment of a robust polyclonal response via vaccination or prior infection reduces the likelihood of this occurring. Infection via antibody-FcR interactions could contribute to pathogenesis in primary infection, systemic virus spread or persistent infection.

Viral Dynamics and Factors Favouring the Duration of Covid-19 Positivity in Cameroon

Background: Evolution evidence of Coronavirus disease 2019 (COVID-19) and viral clearance time remains limited in tropical settings. Understanding this is crucial for public health control measures at community-level. We evaluated the viral dynamics of SARS-CoV-2 infection and factors associated with positivity duration in COVID-19 cases in Cameroon. Method(s): We conducted a prospective cohort-study of SARS-CoV-2 positive cases from the first to third wave (March 2020-October 2021) in Yaounde- Cameroon. RT-PCR was performed on nasopharyngeal swabs. SARS-CoV-2 positivity duration was evaluated from the first to last positive test before a negative result. Epi-info V.7.0 was used for data analyses with p< 0.05 considered statistically significant Results: A total of 282 participants were enrolled. The mean age was 41+/-14 years, with male predominant (62.1%). We had 15.6% symptomatic cases and cough most common (59.09%). The overall median positivity duration was 15[IQR: 9-23] days with 15[ IQR: 13-16] in the first, 17[ IQR: 11-26] in the second and 8[ IQR: 4-12] in the third wave (p= 0.007). Positivity duration was significantly higher in males (16 versus 14 days, p=0.03) and people aged >40 years (15 versus 14 days, p=0.02). Positivity duration was not affected by presence or absence of symptoms (p=0.80). No significant correlation was found with viral load (r=0.03;p=0.61). Considering baseline (24.7+/-7.2Ct) and last viral load (29.3+/-5.9 Ct), the DELTACt (4.6+/-1.3) and positivity duration (15 days) revealed a kinetic in viral decay of 0.3+/-0.087 Ct/day. Conclusion(s): A median positivity duration of 15 days is in accordance with viral clearance around 2 weeks for optimal confinement at community-level. Men and/or the elderly stand at higher risk of prolonged infection. Given the viral decay (0.3 Ct daily), we suggest personalized confinement periods. The variability of positivity duration according to phases could be function of strains which could be a factor of positivity duration.

Impact of elexacaftor/tezacaftor/ivacaftor on Pseudomonas aeruginosa acquisition and chronic infection at a single pediatric cystic fibrosis center

Background: As cystic fibrosis (CF) lung disease progresses, the airways become colonized with opportunistic pathogens such as Pseudomonas aeruginosa secondary to airway surface liquid depletion. Acquisition of P. aeruginosa is associated with decline in lung function and increase in treatment burden and mortality. In October 2019, the Food and Drug Administration approved elexacaftor/tezacaftor/ivacaftor (ELX/TEZ/IVA), a highly effective modulator therapy (HEMT) for individuals aged 12 and older with one copy of the F508del CFTR mutation. ELX/TEZ/IVA increases the amount of and function of CF transmembrane conductance regulator (CFTR) in the respiratory epithelium, increasing mucociliary clearance (MCC) and reducing static airway mucous, a major trigger for chronic infection and inflammation. Method(s): A retrospective analysis of inhaled tobramycin (iTOB) prescriptions prescribed between January 1, 2016, and December 31, 2021, was performed. This captured data before and after ELX/TEZ/IVA approval at Children's Mercy Kansas City (CMKC). The number of individuals with new P. aeruginosa acquisition was determined by identifying electronic prescriptions for iTOB eradication courses. An eradication course was defined as a first lifetime prescription for iTOB or a new prescription for iTOB submitted at least 1 year after a previous prescription. The number of individuals considered chronically infected with P. aeruginosa was determined by identifying individuals receiving chronic iTOB prescriptions and confirmed by respiratory cultures indicating chronic infection based on the Leeds criteria (P. aeruginosa recovered in >=50% of airway cultures in the previous 12 months). Result(s): Eradication courseswere prescribed to 34 individuals in 2016 (15% of people receiving care at CMKC). The number of eradication prescriptions declined in 2020 and 2021, with only 15 (7%) individuals prescribed eradication therapy in 2020 and 12 (5%) in 2021. A similar pattern was observed for prescriptions for chronic infection. In 2016, 57 individuals (25% of our patient population) were receiving iTOB for chronic P. aeruginosa infection. Reductions were seen in 2020 and 2021, with 28 (13%) and 20 (9%) individuals prescribed chronic therapy, respectively. The number of individuals prescribed iTOB for P. aeruginosa eradication and chronic infection per year is represented in Figure 1.(Figure Presented)Conclusions: CMKC experienced a decrease in the number of courses of iTOB prescribed over the last 6 years. HEMT use is associated with greater MCC and anti-inflammatory effects affecting the airway microbiome. The decrease in respiratory cultures growing P. aeruginosa likely reflects these phenomena. A confounding factor is the SARS-CoV-2 pandemic and widespread use of HEMT. Clinic closures and implementation of telemedicine limited in-person patient visits during 2020 and 2021. Despite limited in-person visits, the average number of respiratory cultures per individual at CMKC in 2020 was 3.5, which is consistent with previous years.Wewere able to obtain frequent surveillance cultures through implementation of a drive-through respiratory specimen collection process. Hence, the decrease in number of iTOB courses cannot be attributed to a decrease in frequency of respiratory cultures, although we cannot assess the impact of school closures and a decrease in social gatherings on new P. aeruginosa acquisition or chronic infection. Looking at all these variables, the widespread use of HEMT likely played a significant role in reducing new P. aeruginosa acquisition and chronic P. aeruginosa infection.Copyright © 2022, European Cystic Fibrosis Society. All rights reserved

Metformin prevents the diagnosis of Long Covid in phase 3 trial of early treatment

OBJECTIVES/GOALS: Chronic or new symptoms after infection with severe-acute-respiratory-coronavirus-2 (SARS-CoV-2) has been termed post-acute sequelae of Covid-19 (PASC) or Long Covid. Our objective is to present results from COVID-OUT, a phase 3 double-blind, randomized controlled trial of early outpatient treatment of Covid-19 with repurposed medications. METHODS/STUDY POPULATION: COVID-OUT enrolled adults age 30 to 85 with overweight or obesity who had proof of SARS-CoV-2 infection and fewer than 7 days of symptoms. In this 2 by 3 factorial design trial of metformin, ivermectin, fluvoxamine, or exact-matching placebo of each medication, participants were randomized 1:1:1:1:1:1 to the 6 treatment allocations. This focuses on whether early treatment with metformin prevented Long Covid. Immediate release metformin was titrated to 1500mg daily over the first 6 days. We assessed the incidence of clinician-diagnosed Long Covid with follow up through 10 months after enrollment. We also assessed where participants were diagnosed with Long Covid, and where they received Long Covid treatment. RESULTS/ANTICIPATED RESULTS: Of 1124 participants, 98 (8.7%) report having a healthcare provider make a diagnosis of long covid. By arm, 6.9% (39/564) of metformin participants report having a diagnosis for long covid as compared with 10.5% (59/560) of matched placebo controls. The absolute reduction attributable to metformin was 3.6% (95%CI, 0.3% to 7.0%;P=0.031) with a relative risk reduction of 34% (95%CI, 3% to 55%). The metformin cost per long covid case averted was $28 (95%CI, $15 to $306). 10-month follow-up data will be available at the time of presentation as well as an analysis of baseline factors associated with the development of Long-Covid, independent of treatment allocation in the trial. DISCUSSION/SIGNIFICANCE: Metformin reduced the incidence of clinician-diagnosed long covid by 34% in a double-blind randomized placebo-controlled trial, and previous research published in-vitro activity by metformin against SARS-CoV-2 and other RNA viruses. Further investigation of metformin as early treatment for SARS-CoV-2 is warranted.

CD27-IgD- B cells might portray an exhausted B cell phenotype resulting in lack of response to checkpoint inhibitor treatment in NSCLC

Background Checkpoint inhibitor (CI) therapy has revolutionized the therapy landscape of NSCLC. However, why some patients do not respond to CI therapy remains unknown. The correlation between intra-tumoral B cell follicles and response to CI therapy has been established. B cell follicles within the lymph node become more dispersed with age and CD27-IgD- B cells (DNBc) are described to be age-associated. Moreover, DNBc are abundant in chronic infection, elderly, long COVID and auto-immunity and are described to be anergic and exhausted and often lack expression of CD21. DNBc are expanded in NSCLC tumors compared to healthy lung tissue and inversely correlate to switched memory B cells in the tumor. In this study we explored if there is a correlation between this B cell subtype in peripheral blood of NSCLC patients and response to CI therapy. Methods Patients treated with CIs within the Erasmus Medical Center were included in a prospective observational immunomonitoring study. Nineteen NSCLC patients treated with either Pembrolizumab (Pem) or Nivolumab and 5 healthy controls (HC) were selected. Pem was given in 6/11 responding patients (R) and 5/8 non-responding patients (NR). Peripheral blood mononuclear cells (PBMC) were collected before start of treatment and characterized by multicolor flow cytometry. Results HC and R showed a similar pattern in most B cell subsets. NR had significantly lower proportion of B cells within the PBMC fraction than Rand HC (R: 7.14%, NR: 2.91%, HC: 10.60%). In addition, NR had a significantly higher frequency of DNBc than R and HC (R: 9.43%, NR: 23.78%, HC: 7.19%) and there was no correlation between age and DNBc. The frequency of DNBc correlated positively with lack of CD21 expression (r2: 0.83) and expression of Ki67 (r2: 0.54) both in NR, Rand HC. The frequency of Ki67+CD21-DNBc within the B cell fraction was higher in NR than in R and HC (NR: 18.34%, R: 3.51%, HC: 0.67%). Conclusions We are the first to describe that frequencies of DNBc are higher in NR compared to R and HC. Specifically, Ki67+CD21-DNBc are increased in NR and might reflect an anergic, exhausted B cell phenotype. The absence of a correlation between age and DNBc could suggest that the increase in DNBc is induced by the tumor. Legal entity responsible for the study The authors. Funding Has not received any funding. Disclosure D. Dumoulin: Financial Interests, Personal, Other: Roche, BMS, MSD, AstraZeneca, Novartis. J.G. Aerts: Financial Interests, Personal, Research Grant: Amphera, Roche, Eli Lilly;Financial Interests, Personal, Advisory Board: Amphera, Bristol-Myers Squibb, Eli Lilly, MSD, Roche;Financial Interests, Personal, Ownership Interest: Amphera;Financial Interests, Personal, Other: Takeda. All other authors have declared no conflicts of interest.Copyright © 2023 International Association for the Study of Lung Cancer. Published by Elsevier Inc.

Chronic HIV infection influences the immune response during acute COVID-19 and long COVID

OBJECTIVES/GOALS: Despite highly effective antiretroviral therapy, people living with HIV (PLWH) experience chronic immune activation and inflammation which may influence the progression of infections such as SARS-CoV-2. Here, we explore the immune response and clinical outcomes in HIV(+) and HIV(-) individuals experiencing acute COVID-19 and long COVID (LC). METHODS/STUDY POPULATION: We performed flow cytometric analyses on peripheral blood mononuclear cells from the following: 1) HIV(-) individuals experiencing acute COVID-19, 2) PLWH experiencing acute COVID-19, and 3) pre-COVID-19 pandemic PLWH. Additionally, we will perform similar analyses for the following: 1) PLWH experiencing LC, 2) PLWH previously infected with SARS-CoV-2 who recovered, 3) pre-COVID-19 pandemic PLWH, and 4) HIV(-) individuals experiencing LC. Flow cytometry panels include surface markers for immune cell populations, activation and exhaustion surface markers (with and without SARS-CoV-2-specific antigen stimulation), and intracellular cytokine staining. We will also analyze how chronic HIV infection and other clinical and demographic factors (e.g., age, CD4 %) impact persistent symptomatic burden. RESULTS/ANTICIPATED RESULTS: Acute COVID-19 results–Overall, PLWH had higher baseline expression of activation markers OX40 and CD137 on CD4+ and CD8+ T cells, along with increased levels of TNFa producing CD8+ T cells. Interestingly, PLWH had increased expression of exhaustion markers PD1 and TIGIT but decreased expression of TIM3 on CD4+ and CD8+ T cells. Additionally, PLWH had decreased levels of IL-2 and IFNg producing CD4+ T cells which suggests functional exhaustion. Long COVID-19 expected results–we hypothesize that the activation and inflammation seen in chronic HIV infection will lead to more immune dysregulation and subsequently worsened symptomatic burden. Additionally, we hypothesize that PLWH may have different frequencies of certain LC manifestations, such as increased rates of neurocognitive impairment. DISCUSSION/SIGNIFICANCE: Our findings suggest that chronic HIV infection influences acute immune response during SARS-CoV-2 infection, and that PLWH have variable expression of exhaustion markers which warrants further study. Additionally, our findings in the LC cohort will aid in characterizing clinical manifestations and immunologic mechanisms of LC in PLWH.

Does Kaftrio® reduce IV antibiotic burden in cystic fibrosis? A retrospective observational evaluation

AimRespiratory failure remains the most common cause of death in Cystic Fibrosis (CF) with chronic/complex infection a significant contributory factor. Infection frequency and associated treatment burden increase the risk drug-resistant organisms;however, stewardship strategies are challenging to translate to CF care.The CFTR modulator Kaftrio® (elexacaftor/tezacaftor/ivacaftor) launched in the UK in August 2020. Initial phase 3 clinical trials1 2 and a subsequent open-label extension study3 demonstrated promising data on health-related quality of life, including reduced pulmonary exacerbation (PEx) rates (63%), hospitalisation (71%) and PEx requiring IV antibiotics (78%). This evaluation aimed to provide a ‘real-world' review of the impact of Kaftrio® on IV antibiotic burden (admission rates, ‘bed-days', bed-day cost, total IV antibiotic use and ‘AWaRE' antibiotic use) in CF patients aged 12–16 years at a single tertiary centre.MethodA single-centre retrospective observational evaluation was conducted. All 12–16 year olds on Kaftrio® were identified using the local CF database. For each patient: month/year Kaftrio® commenced and prior CFTR modulator therapy were determined. Clinical trial patients were excluded. Digital clinical information systems were used to identify ‘chest-related' admissions for IV antibiotics in the 24 months prior to starting Kaftrio® and the treatment period post, up to June 2022. For each admission, drugs, doses administered and ‘IV antibiotic bed-days' were determined. ‘Bed-day' costs were calculated and use of ‘Restricted' or ‘Watch' antibiotics (WHO AWaRE/local Policy) were identified. IV antibiotic burden pre- and post Kaftrio® was evaluated.Results44 admissions in 33 patients were identified prior to Kaftrio®, compared with 13 admissions post-Kaftrio®, demonstrating a 65–70% overall reduction in admissions (PEx: rate 66/100patient/year vs 23/100patient/year). Pre-Kaftrio® 639 ‘bed days'/24 months were directly attributed to delivery of IV antibiotics-a total estimated cost of £383,400 (estimate £600/day/medical bed). From October 2020-June 2022, the number of IV antibiotic ‘bed days' fell to 183. A total reduction of 71%, with an estimated cost saving of £273,600. In the 24 months prior to Kaftrio® a total 2849 doses of IV antibiotics were administered vs 657 doses in the same patient cohort in the period post-Kaftrio® to June 2022, an absolute reduction of 2192 doses (77%). Of the 2849 IV antibiotics pre-Kaftrio® doses, 84% were restricted/watch antibiotics (R=706;W= 1681). Usage dropped by 37.5% and 89% respectively post-Kaftrio®.ConclusionResults suggest Kaftrio® reduces overall IV antibiotic burden in CF patients, providing real-word data supporting the phase 3 study outcomes. Significant reductions in PEx rates, IV antibiotic use, ‘bed days' and associated costs were all observed. Data demonstrated an absolute reduction in the use of ‘AWaRE' antibiotics, although use still accounts for a high overall proportion in this cohort. Results are limited by the data periods. Potential impact of the COVID-19 pandemic on PEx rates (‘shielding' population) should be considered. Nonetheless, the significance of these findings on overall outcomes and stewardship should not be downplayed. Ongoing review, including expanded patient populations (adults;6–11 years) is essential. Further works looking at oral antibiotics use, epidemiology, genotype and previous CFTR treatment would support extended evaluation of the overall impact of Kaftrio® on infection management in CF.ReferencesMiddleton PG, Mall MA, Drevineck P, et al. Elexacaftor-tezacaftor-ivacaftor for Cystic Fibrosis with a single Phe508del Allele. New England Journal of Medicine 2019;381:1809–1819.Southern K, Murphy J, Sinha I, et al. Corrector therapies (with or without potentiators) for people with cystic fibrosis with class II CFTR gene variants. Cochrane Database of Systematic Review 2020;12;1–313.Griese M, Costa, S, Linnemann R, et al. Safety and e ficacy of Elexacaftor/Tezacaftor/Ivacaftor for 24 weeks or longer in people with cystic fibrosis and one or more F598del Allele: Interim Results of an Open-Label Phase 3 Clinical Trial. American Journal of Respiratory and Critical Medicine 2021;203;381–384.

Age-related changes in the immune system and the consequences of immunosenescence

The cellular and molecular hallmarks of aging include genomic instability, telomere attrition, epigenetic alterations, changes in intracellular signaling, cellular senescence, and mitochondrial dysfunction. These lead to complex remodeling and changes involving both the innate and adaptive immune systems. Besides age related changes in immune cells, the microenvironment in the lymphoid and non-lymphoid organs, as well as circulating factors interacting with the immune system also contribute to immunosenescence. Overall, immunosenescence is characterized by reduction of immune response, an increase in inflammatory and oxidation background (inflamm-aging), and production of autoantibodies. One of the most prominent age-related changes in the adaptive immune system is the decline in regenerative thymic capacity. Similar aging related defects have also been observed in stroma of the bone marrow. While lymphocytes in infants show a naive phenotype, memory phenotype predominates after midlife. Though immune responses against recall antigens may still be conserved, the ability to mount primary response against novel antigens declines with age. As a result, increased susceptibility to infections, and suboptimal vaccine response is observed in the elderly. Apart from functional alternation in immune cells, there is a low-grade persistent elevation in inflammatory molecules. Inflamm-aging may result from the accumulation of misfold proteins, compromised gut barrier function, chronic infection, obesity, etc. Furthermore, aging is associated with immune dysregulation, with defective resolution of immune response after activation, and impaired clearance of dead cells with sustained inflammation. Excessive inflammation not only impairs antigen specific immunity, but also leads to tissue damage. In fact, this may partly account for the increased mortality of COVID infection in the elderly. Apart from vulnerability to infection and weakened vaccine response, immunosenescence also plays an important role in cancer and autoimmunity in the elderly. Because of increased tissue damage and apoptosis, coupled with inflamm-aging, increased autoantibodies production is observed in the elderly. Nevertheless, there is an age-related increase in peripheral regulatory T cells. While there is an increase in autoimmunity with aging, this does not always translate into an increase in autoimmune disease. On the other hand, the increase in regulatory T cells, along with other immunosuppressive cells and the senescence associated proinflammatory environment, promotes tumor development and progression in the elderly. As immunosenescence has a significant impact on health and disease, better understanding on this process is crucial for research and development in the future geriatric health care.

Decentralised point-of-care testing for acute, chronic and infectious disease - benefits and challenges

The COVID-19 pandemic has reinforced Australia's need for diagnostic testing frameworks that are well-prepared, well-resourced, responsive, appropriately governed, scalable, interdisciplinary and collaborative.1 Point-of-care (POC) technologies offer diagnostic solutions capable of delivering individual, community and public health benefits in settings where: a) laboratory testing is not available, b) rapid turn-around time is needed, c) high loss to follow-up occurs in high-risk populations with standard of care cascades and/or d) disease transmission rates exceed laboratory response capacity. Key translational research derived from collaborative point-of-care testing networks for a) diabetes management (238 remote health services;3,233 operators;172,069 HbA1c and 51,379 urine albumin:creatinine ratio tests), b) acute care (106 remote health services;2,279 operators;32,950 blood gas, 32,689 cardiac troponin, 46,418 urea/electrolytes, 48,193 international normalised ratio tests), c) hepatitis C virus (HCV) (41 sites;110 operators;5,733 HCV tests;4,978 RNA, 755 antibody), d) syphilis screening (156 sites;1,412 operators), e) chlamydia, gonorrhea or trichomonas (51 sites;795 operators;>50,000 tests) or f) COVID-19 (101 remote health services, 733 operators, 72,624 tests) will be used to highlight operational, clinical, public health, and economic benefits of POC testing. Challenges associated with scale-up and accreditation pathways for decentralised POC testing will be discussed. Reference 1. Revised Testing Framework for COVID-19 in Australia, March 2022 Version 2.1. Communicable Disease Network Australia and Public Health Laboratory Network. Copyright © 2022

Serological response to SARS-CoV- 2 in patients under immunomodulatory treatment for rheumatoid arthritis

Background/Purpose: To determine and compare the magnitude of humoral immune response after the first, second, and third and overall exposure to SARS-CoV- 2, either by natural infection or vaccination, between rheumatoid arthritis (RA) patients under various immunosuppressive treatments and healthy controls (HCs). Method(s): Blood samples from various time points before and after the COVID-19 pandemic and longitudinal data on exposure history were obtained from RA patients and HCs recruited for this study. Antibody levels were then determined using indirect ELISA and statistically analysed in relation to exposure history. Result(s): A significant rise in antibody levels after overall exposure to SARS-CoV- 2 in RA patients and HCs was found, with no significant difference between the two groups. Amongst RA patients, a progressive rise in antibodies following each exposure to SARS-CoV- 2 was found, with antibody levels rising above the cut-off for seropositivity following the second and third exposures. Incidentally, HCs, despite having high antibody levels following the first and second exposure, were found to have antibody levels below the cut-off for seropositivity upon their third exposure to SARS-CoV- 2. Conclusion(s): Contrary to popular belief, RA patients, despite under immunosuppressive treatments, are capable of eliciting a humoral response that is comparable to that of healthy individuals. The lower antibody levels found in HCs by third exposure could signify that more vaccine boosters may be required to increase the public's immunity against SARS-CoV- 2 for herd immunity and avoid creating a reservoir for the emergence of novel variants with persistent infections.

Accelerated SARS-CoV-2 intrahost evolution leading to distinct genotypes during chronic infection.

The chronic infection hypothesis for novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variant emergence is increasingly gaining credence following the appearance of Omicron. Here, we investigate intrahost evolution and genetic diversity of lineage B.1.517 during a SARS-CoV-2 chronic infection lasting for 471 days (and still ongoing) with consistently recovered infectious virus and high viral genome copies. During the infection, we find an accelerated virus evolutionary rate translating to 35 nucleotide substitutions per year, approximately 2-fold higher than the global SARS-CoV-2 evolutionary rate. This intrahost evolution results in the emergence and persistence of at least three genetically distinct genotypes, suggesting the establishment of spatially structured viral populations continually reseeding different genotypes into the nasopharynx. Finally, we track the temporal dynamics of genetic diversity to identify advantageous mutations and highlight hallmark changes for chronic infection. Our findings demonstrate that untreated chronic infections accelerate SARS-CoV-2 evolution, providing an opportunity for the emergence of genetically divergent variants.

Diagnosis of COVID-19 in a geriatric patient hospitalised for fall with initial misinterpreted aspiration pneumonia

Background. SARS-CoV-2 is a virus which is more aggressive in aged patients with associated chronic age-related diseases. Although it is known that clinical picture of COVID-19 is already multifaceted, very little is still known about the infectious syndrome in aged patients. We present a case of an aged patient hospitalized for fall affected from COVID-19 pneumonia, initially misinterpreted for an aspiration pneu-monia. Case presentation. We describe the case of a 92 years patient with chronic heart diseases, hospitalized for fall complicated by head trau-ma. She was diagnosed with an aspiration pneumonia due to the fall so that she was put under antibiotics treatment. Despite four days of antibiotics treatment, the patient presented high fever and dry cough motivating in an epidemic period the nasopharyngeal PCR test for the research of SARS-CoV-2 which resulted positive. Discussion and conclusions. Aspiration pneumonia resulting from a fall is a common finding in geriatric patients, that's why the diagnosis of COVID-19 was delayed. The geriatric population often have an altered clinical presentation of diseases, in particular regarding infectious diseases. The correct interpretation of some suspicious findings such as regular blood tests would have led more quickly to a diagnosis of non-aspiration pneumonia. Inflammatory markers and white blood cell count resulted within the normal range. Moreover, lymphopenia, considered as one of the biological1. The presence of confusion as a sign of persisting infection in an older patient should not be under-estimated, expression of a possible involvement of nervous system in SARS-CoV-2 infection2. The common diagnosis of aspiration pneumonia in the geriatric field, the aspecific signs and symptoms of COVID-19 disease, the complex picture of our patient, prove that in geriatrics an apparently simple diagnosis could instead be insidious and complex. Copyright © by Societa Italiana di Gerontologia e Geriatria (SIGG).

Successful Treatment of Persistent Severe Acute Respiratory Syndrome Coronavirus 2 Infection in an Immunocompromised Patient

Background. The COVID-19 pandemic has been marked by long-term persistence of SARS-CoV-2 in immunocompromised patients receiving B-cell-depleting therapies, with many individuals experiencing fatal COVID-19. Methods. We report an individual treated with rituximab who survived persistent COVID-19 over 9 months. SARS-CoV-2 positive RNA samples were sequenced using targeted amplicon NGS sequencing with backup sequencing on a nanopore platform. The resulting sequences were analyzed for genomic variance over time at the consensus and sub-consensus level. Results. An individual with rheumatoid arthritis (RA) treated with azathioprine and rituximab (last dose in May 2020) was diagnosed with COVID-19 in July 2020 and admitted with pneumonia. After initial incomplete recovery, the patient had persistent infection through March 2021 and received both remdesivir and convalescent plasma (January 2021). The patient received three doses of mRNA vaccine (Pfizer BioNTech) in December 2020, April 2021, and November 2021, but was seronegative for nucleocapsid IgG in both January 2021 and March 2021;positive spike IgG developed by September 2021 (512 AU/ml) and December 2021 (621 AU/ml) (Figure 1). The patient recovered with new oxygen dependence (2-3L) and manages RA off B-cell depletion;they required an extended corticosteroid taper to manage organizing pneumonia and treatment for several opportunistic infections. Viral sequencing over the course of illness indicated a persistent infection with a lineage B.1.585.3 virus that accumulated 14 mutations throughout the infection. Two mutations (S494P, S D737Y) are associated with therapy resistance and are similar to those found in other immunocompromised individuals with persistent COVID-19. Additional mutations were of unknown consequence Conclusion. SARS-CoV-2 was able to establish persistent infection and accumulated mutations associated with therapeutic resistance;repeated vaccination was associated with successful resolution following repeated vaccination after stopping rituximab. Cessation of B-cell-depleting therapy was likely the critical factor in the patient's recovery, but repeated vaccination was associated with a delayed seroconversion in this patient with reversibly immunosuppression.

Novel checkpoint modifier lowers T cell activation threshold and enhances and broadens vaccine-induced responses to chronic viral infections

Background. Vaccines aim to induce immune responses that prevent disease. They may also clear chronic infections or reduce tumor progression. Vaccine adjuvants augment immune responses, in general, by providing stimulatory signals. Our focus has been on a different type of adjuvant that enhances vaccine-induced T cell responses by modulating the herpes virus entry mediator (HVEM) pathway. The B and T cell attenuator (BTLA) is expressed on naive T cells and, upon binding to HVEM on antigen presenting cells, dampens signaling through the T cell receptor. HVEM binds with a different domain to the co-stimulator LIGHT. Within a trimolar BTLA-LIGHT/HVEM complex, inhibition prevails. Herpes simplex virus (HSV-1) glycoprotein D (gD) attaches to the BTLA binding site of HVEM and as it has higher binding affinity outcompetes BTLA binding and allows for co-stimulation through LIGHT. This results in enhanced signaling through the T cell receptor and thereby augments and broadens CD8+ T cell responses as we showed with chimpanzee adenovirus (AdC) vector vaccines for several viral antigens. Methods. Immunogenicity in rodents was evaluated following one or two immunizations with AdC vectors expressing antigens of HIV (gag), HPV-16 (E7/6/5), HBV (core & pol), influenza virus (nucleoprotein) and SARS-CoV2 (nucleoprotein), with or without gD. Vaccine-induced CD8+ T cell responses, including their magnitude, functions, duration, and breadth were characterized. Vaccine efficacy was also evaluated. Results. Vaccination with gD-antigen fusion proteins increased CD8+ T cell frequencies to all of the antigens tested (Fig) and improved efficacy. Addition of gD increased stimulation of CD8+ T cells to subdominant epitopes and thereby enhanced breadth of responses. Conclusion. Checkpoint modification of the HVEM pathway with a gD-antigen fusion protein produces potent, prolonged, and broad responses of CD8+ T cells to immunodominant and subdominant epitopes. The latter is especially important for chronic viral infections, where, due to exhaustion of T cells to dominant epitopes therapeutic efficacy of vaccines may rely on expansion of T cells to subdominant epitopes. Clinical studies to evaluate therapeutic vaccination for chronic HBV are planned. (Figure Presented).