Risk control of host cell proteins in one therapeutic antibody produced by concentrated fed-batch (CFB) mode

Multiple control strategies, including a downstream purification process with well-controlled parameters and a comprehensive release or characterization for intermediates or drug substances, were implemented to mitigate the potential risk of host cell proteins (HCPs) in one concentrated fed-batch (CFB) mode manufactured product. A host cell process specific enzyme-linked immunosorbent assay (ELISA) method was developed for the quantitation of HCPs. The method was fully validated and showed good performance including high antibody coverage. This was confirmed by 2D Gel-Western Blot analysis. Furthermore, a LC-MS/MS method with non-denaturing digestion and a long gradient chromatographic separation coupled with data dependent acquisition (DDA) on a Thermo/QE-HF-X mass spectrometer was developed as an orthogonal method to help identify the specific types of HCPs in this CFB product. Because of the high sensitivity, selectivity and adaptability of the new developed LC-MS/MS method, significantly more species of HCP contaminants were able to be identified. Even though high levels of HCPs were observed in the harvest bulk of this CFB product, the development of multiple processes and analytical control strategies may greatly mitigate potential risks and reduce HCPs contaminants to a very low level. No high-risk HCP was identified and the total amount of HCPs was very low in the CFB final product.

Association of body mass index and intestinal (faecal) Streptococcus in adults in Xining city, China P.R

Body mass index (BMI) and gut microbiota show significant interaction, but most studies on the relationship between BMI and gut microbiota have been done in Western countries. Relationships that are also identified in other cultural backgrounds are likely to have functional importance. Hence here we explore gut microbiota in adults living in Xining city (China P.R.) and relate results to subject BMI. Analysis of bacterial 16s rRNA gene was performed on faecal samples from participants with normal-weight (n=24), overweight (n=24), obesity (n=11) and type 2 diabetes (T2D) (n=8). The results show that unweighted but not weighted Unifrac distance was significantly different when gut microbiota composition was compared between the groups. Importantly, the genus Streptococcus was remarkably decreased in both obese subjects and subjects suffering from T2D, as compared to normal-weight subjects. Accordingly, strong association was identified between the genus Streptococcus and BMI and especially Streptococcus salivarius subsp. thermophiles was a major contributor in this respect. As previous studies have shown that Streptococcus salivarius subsp. thermophiles is also negatively associated with obesity in Western cohorts, our results suggest that this species is a potential probiotic for the prevention of obesity and related disorders.

Characterization of light chain c-terminal extension sequence variant in one bispecific antibody

Protein modifications such as post-translational modifications (PTMs) and sequence variants (SVs) occur frequently during protein biosynthesis and have received great attention by biopharma industry and regulatory agencies. In this study, an aberrant peak near light chain (LC) was observed in the non-reduced capillary electrophoresis sodium dodecyl sulfate (nrCE-SDS) electrophoretogram during cell line development of one bispecific antibody (BsAb) product, and the detected mass was about 944 Da higher than LC. The corresponding peak was then enriched by denaturing size-exclusion chromatography (SEC-HPLC) and further characterized by nrCE-SDS and peptide mapping analyses. De novo mass spectra/mass spectra (MS/MS) analysis revealed that the aberrant peak was LC related sequence variant, with the truncated C-terminal sequence “SFNR” (“GEC”deleted) linked with downstream SV40 promotor sequence “EAEAASASELFQ”. The unusual sequence was further confirmed by comparing with the direct synthetic peptide “SFNREAEAASASELFQ”. It was demonstrated by mRNA sequencing of the cell pool that the sequence variant was caused by aberrant splicing at the transcription step. The prepared product containing this extension variant maintained well-folded structure and good functional properties though the LC/Heavy chain (HC) inter-chain disulfide was not formed. Several control strategies to mitigate the risk of this LC related sequence variant were also proposed.

The Bone Sialoprotein RGD Domain Modulates and Maintains Periodontal Development

Bone sialoprotein (gene: Ibsp; protein: BSP) is a multifunctional extracellular matrix protein present in bone, cementum, and dentin. Accumulating evidence supports BSP as a key regulator of mineralized tissue formation via evolutionarily conserved functional domains, including a C-terminal integrin-binding Arg-Gly-Asp (RGD) domain implicated in extracellular matrix-cell signaling. Ablation of Ibsp in mice (Ibsp-/-) results in impaired bone growth and mineralization and defective osteoclastogenesis, with effects in the craniofacial region including reduced acellular cementum formation, detachment of the periodontal ligament (PDL), alveolar bone hypomineralization, and severe periodontal breakdown. We hypothesized that BSP-RGD plays an important role in cementum and alveolar bone formation and mineralization, as well as periodontal function. This hypothesis was tested by replacing the RGD motif with a nonfunctional Lys-Ala-Glu (KAE) sequence in (IbspKAE/KAE) mice and OCCM.30 murine (IbspKAE) cementoblasts. The RGD domain was not critical for acellular or cellular cementum formation in IbspKAE/KAE mice. However, PDL volume and thickness were increased, and significantly more tartrate-resistant acid phosphatase-positive osteoclasts were found on alveolar bone surfaces of IbspKAE/KAE mice versus wild type mice. PDL organization was disrupted as indicated by picrosirius red stain, second harmonic generation imaging, dynamic mechanical analysis, and decreased asporin proteoglycan localization. In vitro studies implicated RGD functions in cell migration, adhesion, and mineralization, and this was confirmed by an ossicle implant model where cells lacking BSP-RGD showed substantial defects as compared with controls. In total, the BSP-RGD domain is implicated in periodontal development, though the scale and scope of changes indicated by in vitro studies indicate that other factors may partially compensate for and reduce the phenotypic severity of mice lacking BSP-RGD in vivo.

Application of deep learning in the real-time diagnosis of gastric lesion based on magnifying optical enhancement videos

Background and aim

Magnifying image-enhanced endoscopy was demonstrated to have higher diagnostic accuracy than white-light endoscopy. However, differentiating early gastric cancers (EGCs) from benign lesions is difficult for beginners. We aimed to determine whether the computer-aided model for the diagnosis of gastric lesions can be applied to videos rather than still images.

Methods

A total of 719 magnifying optical enhancement images of EGCs, 1,490 optical enhancement images of the benign gastric lesions, and 1,514 images of background mucosa were retrospectively collected to train and develop a computer-aided diagnostic model. Subsequently, 101 video segments and 671 independent images were used for validation, and error frames were labeled to retrain the model. Finally, a total of 117 unaltered full-length videos were utilized to test the model and compared with those diagnostic results made by independent endoscopists.

Results

Except for atrophy combined with intestinal metaplasia (IM) and low-grade neoplasia, the diagnostic accuracy was 0.90 (85/94). The sensitivity, specificity, PLR, NLR, and overall accuracy of the model to distinguish EGC from non-cancerous lesions were 0.91 (48/53), 0.78 (50/64), 4.14, 0.12, and 0.84 (98/117), respectively. No significant difference was observed in the overall diagnostic accuracy between the computer-aided model and experts. A good level of kappa values was found between the model and experts, which meant that the kappa value was 0.63.

Conclusions

The performance of the computer-aided model for the diagnosis of EGC is comparable to that of experts. Magnifying the optical enhancement model alone may not be able to deal with all lesions in the stomach, especially when near the focus on severe atrophy with IM. These results warrant further validation in prospective studies with more patients. A ClinicalTrials.gov registration was obtained (identifier number: NCT04563416).

Clinical Trial Registration

ClinicalTrials.gov, identifier NCT04563416.

A novel IgG fc by computer-aided design enhances heavy-chain heterodimerization in bi- or tri-specific antibodies

Background

The classical “Knob-into-holes” (KIH) strategy (knob(T366Y)/hole (Y407T)) has successfully enhanced the heterodimerization of a bispecific antibody (BsAb) resulting in heterodimer formation up to 92% of protein A (ProA)-purified protein pool. However, it does not show high efficiency for every BsAb.

Methods

KIH was initially applied to a CD20/CD3 BsAb. After in-silico modeling, two additional new mutations, S354Y in knob-heavy chain (HC) and Q347E in hole-HC, together with KIH named “ETYY”, were introduced in the Fc. Functional and physicochemical assays were performed to assess the BsAb.

Results

The CD20/CD3 BsAb hybrid only represented ~ 50% of the ProA-purified protein pool when KIH was applied. With ETYY, the percentage of CD20/CD3 hybrid increased to 93.8% in the ProA-purified protein pool and facilitated the second purification via ion-exchange chromatography. S354Y in the knob-HC introduced a hydrophobic interaction with Y349 on the hole-HC, and Q347E on the hole-HC introduced an ionic interaction with K360 on the knob-HC. CD20/CD3-v4b (containing ETYY) retains the original activity of the BsAb at both Fab and Fc regions. Its melting temperature is > 65 °C and aggregation temperatures (Tagg)266 and Tagg473 are both > 70 °C, indicating high thermostability. The dynamic light scattering (DLS) assay shows only one peak with the size of an IgG molecule with PDI of 0.121, indicating low aggregation potential of the BsAb.

Conclusions

This computer-aided novel ETYY design of BsAb Fc facilitates enhanced heterodimerization while retaining functional and physicochemical properties. This has the potential to improve the development of next-generation BsAbs with higher yields and simpler purification.

[Protective effect of excretory-secretory proteins from Trichinella spiralis muscle larvae against myocardial injury in septic mice]

OBJECTIVE

To evaluate the protective effect of excretory-secretory proteins from Trichinella spiralis muscle larvae (Ts-MES) on sepsis-induced myocardial injury in mice.

METHODS

Eighty male BALB/C mice were randomized equally into sham-operated group, myocardial injury group, Ts-MES treatment group and dexamethasone treatment group. In the latter 3 groups, sepsis-induced myocardial injury models were established by cecal ligation and perforation; the sham operation was performed by exposure of the cecum without ligation or perforation. Forty minutes after the operation, the mice were given intraperitoneal injections 150 μL PBS, 20 μg TS-MES or 0.3 mg/kg dexamethasone as indicated. At 12 h after the operation, 6 mice were randomly selected from each group for echocardiography, and 8 mice were used for observing the survival rate within 72 h. The remaining 6 mice were examined for myocardial pathologies with HE staining and serum levels of NTPro-BNP and cTnI with ELISA; the expressions of TNF-α, IL-6, IL-10 and TGF-β in the serum and myocardial tissue were detected using ELISA and qRT-PCR.

RESULTS

Compared with the sham-operated mice, the septic mice showed significantly decreased cardiac function indexes (LVEF, LVFS, and E/A) with lowered survival rate within 72 h (P < 0.001) and significantly higher myocardial injury scores and serum levels of NTPro-BNP and cTnI (P < 0.01). Treatment with TS-MES significantly improved the cardiac function and 72-h survival rate (P < 0.05) and lowered the myocardial injury scores and serum levels of NTPro-BNP and cTnI (P < 0.05) in the septic mice. Compared with the sham-operated mice, the septic mice had obviously increased TNF-α and IL-6 levels in the serum and myocardial tissue (P < 0.001), which were significantly lowered by treatment with TS-MES (P < 0.05). TS-MES and dexamethasone both increased the levels of IL-10 and TGF-β in the septic mice, but the changes were significant only in TS-MES-treated mice (P < 0.05).

CONCLUSION

Ts-MES are capable of protecting against myocardial injury in septic mice by reducing the production of pro-inflammatory cytokines and enhancing the levels of regulatory cytokines.

[Inflammatory factors in periodontitis patients and their effects toward the occurrence of gestational diabetes mellitus: a case-control study]

Objective: To explore the effects of periodontitis and inflammatory factors toward the occurrence of gestational diabetes mellitus (GDM). Methods: Pregnant women who came to the Department of Obstetrics, Northwest Women's and Children's Hospital for prenatal examinations during March to November of 2021 were invited to participate in this study. Participants with GDM who met the inclusion criteria (n=100) were assigned into the case group; while healthy participants (n=100) were assigned into the control group. Information of participants from the two groups were collected by questionnaires and periodontal statuses were clinically recorded in the meantime. Gingival crevicular fluid (GCF) and venous blood were also collected from participants of two groups to analyze the expression levels of inflammatory factors like C-reactive protein (CRP), tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-6, IL-8, IL-10 and IL-33. Factors different between the two groups were included in the multivariate regression analysis model to determine the risk factors of GDM. Results: The age of participants was (33.4±5.1) years in case group and (30.5±4.5) years in control group respectively, which had statistical differences (t=4.33,P<0.001). Besides, the body mass index of participants from case group was also significantly higher than control group [(28.11±3.85) kg/m² vs. (23.31±3.15) kg/m², t=9.65, P<0.001]. Participants with GDM had more adverse periodontal clinical parameters. Prevalence of periodontitis in GDM group was 47.0% (47/100) compared with 29.0% (29/100) in control group (χ²=6.88, P=0.009). Multivariate regression analysis results indicated that periodontitis was a critical risk factor for the occurrence of GDM (OR=1.882, P<0.001). Besides, GCF IL-8, serum TNF-α, IL-8 and IL-10 were also risk factors of GDM due to their higher expressions. Among them, TNF-α in serum (OR=2.077) and IL-8 in serum (OR=2.060) had more significant impacts (P<0.001). Conclusions: This study demonstrated that periodontitis was associated with the occurrence of GDM. Up-regulation of serum pro-inflammatory mediators leaded by local periodontal inflammatory microenvironment might play a critical role in this pathological process.

POS0200 POST-mRNA VACCINE FLARES IN AUTOIMMUNE INFLAMMATORY RHEUMATIC DISEASES: INTERIM RESULTS FROM THE CORONAVIRUS NATIONAL VACCINE REGISTRY FOR IMMUNE DISEASES SINGAPORE (CONVIN-SING)

Background

Published data suggest no increased rate of flare of autoimmune inflammatory rheumatic diseases (AIIRD) after COVID-19 mRNA vaccination; however, the studies are limited by small sample size, short follow up or at risk of selection bias (voluntary physician reports or patient surveys).

Objectives

To study flares of AIIRD within three months of the first dose of an anti-SARS-COV2 mRNA vaccine.

Methods

A retrospective cohort study of consecutive AIIRD patients ≥ 12 years old, across six public hospitals in Singapore who received at least one dose of an mRNA (Pfizer/BioNTech or Moderna) vaccine. Data were censored at the first post-vaccine clinic visit when the patient had flared or if ≥ three months had elapsed since the first dose of the vaccine, whichever came first. Predictors of flare were determined by Cox proportional hazards analysis and time to flare was examined using a Nelson Aalen cumulative hazard estimate (Figure 1).

Figure 1.

Nelson-Aalen curve of flares over time

Results

2339 patients (74% Chinese, 72% female) of median (IQR) age 64 (53, 71) years were included in the interim analysis (Table 1). 2112 (90%) had the Pfizer/BioNTech vaccine and 195 (8%) had Moderna, with a median (IQR) interval of 21 (21, 23) days between the two doses. The most common AIIRD diagnoses were Rheumatoid arthritis (1063, 45%), Psoriatic arthritis (296, 12.6%) and Systemic lupus erythematosus (SLE) (288, 12.3%). 186 (8%) were treated with biologics/ targeted disease modifying agents. 2125 (91%) patients were in low disease activity or remission. Treatment was interrupted for vaccination in only 18 (0.8%) patients. Seven (0.3%) patients had previous COVID-19 infection.

Table 1.

Patient characteristics

Baseline characteristicsNo flares(n = 1887, %)Flares within 0—3 months of 1st vaccine dose (n= 272, %)Flares outside of 0 – 3 months after 1st vaccine dose (n = 180, %)Age (median years, IQR)64 (53, 71)61 (50, 69)65 (55, 71)RaceChinese1386 (73)206 (76)129 (72)Malay193 (10)28 (10)20 (11)Indian195 (10)27 (10)26 (14)GenderFemale1367 (72)200 (74)117 (65)Vaccine typePfizer/BioNTech1713 (92)239 (90)160 (90)Moderna149 (8)28 (10)18 (10)DiagnosisRheumatoid Arthritis831 (44)139 (51)93 (52)Systemic Lupus Erythematosus269 (14)20 (7)9 (5)Psoriatic Arthritis225 (12)42 (15)29 (16)Spondyloarthropathies141 (7)21 (7)17 (9)Sjogren’s Syndrome114 (6)15 (6)8 (4)Systemic sclerosis94 (5)4 (1)6 (3)Baseline Physician Disease ActivityRemission1007 (53)99 (36)63 (35)Low Disease Activity731 (39)128 (47)97 (54)Moderate Disease Activity134 (7)40 (15)20 (11)High Disease Activity15 (1)5 (2)0

452 (19%) flares were recorded during 9798.8 patient-months [4.6/100 patient-months, median (IQR) follow up duration 4.2 (3.3, 5.3) months], of which 272 (11.6%) patients flared within the 3-month period of interest and 180 (7.7%) flared outside of the 3-month period (Table 1). Median (IQR) time-to-flare was 40.5 (18, 56.6) days. 60 (22.1%) were mild and self-limiting, 170 (62.5%) were mild-moderate and 42 (15.4%) were severe. 190 (69.8%) of those who flared required escalation of treatment and 15 (5.5%) required hospital admission. 239 (10.2%) had improved disease activity after the vaccine.

On multivariate Cox regression analysis, patients in the oldest age tertile [median (IQR) 74 (71, 79) years] were less likely to flare [HR 0.80 (95% CI 0.63, 1.00), p = 0.05] Patients with inflammatory arthritis (compared with connective tissue disease, vasculitis and others) and patients with baseline active disease were more likely to flare [HR 1.72 (95% CI 1.35, 2.20), p < 0.001 and 1.82 (95% CI 1.39, 2.39), p < 0.001 respectively]

Conclusion

There was a moderately high rate of AIIRD flares after mRNA vaccination; however, there was no clustering of flares in the immediate post-vaccine period to suggest causality. Older patients were less likely to flare, while those with inflammatory arthritis and active disease at baseline were more likely to flare.

Disclosure of Interests

Margaret Ma Grant/research support from: Support grant from multiple companies for the Singapore Biologics registry, Amelia Santosa Speakers bureau: Amgen Talk, Consultant of: Pfizer ad board, Kok Ooi Kong: None declared, Chuanhui Xu: None declared, Johnston Tang Gin Xiang: None declared, Gim Gee Teng Speakers bureau: Boehringer Ingleheim, Anselm Mak Speakers bureau: J&J and GSK, Grant/research support from: GSK - the supported studies programme, Sen Hee Tay: None declared, Victoria Wei Wen Ng: None declared, Joshua Zhi En Koh: None declared, Warren Fong Speakers bureau: speaker for Abbvie, DKSH, GSK, Novartis, Li-Ching Chew Speakers bureau: pfizer and Abbvie, Consultant of: Pfizer and Abbvie Advisory Board meeting, Grant/research support from: Abbvie educational grant for ultrasound conference, Andrea Low Speakers bureau: Boehringer Ingeilheim, Consultant of: Consultant/steering group committee for BI and J&J, annie law: None declared, Yih Jia Poh: None declared, Siaw Ing Yeo Grant/research support from: Multiple pharmaceutical companies for the support of the National Biologics Registry, Ying Ying Leung Speakers bureau: Abbvie, DKSH, Jassen, Novartis and Pfizer, Wei-Rui Goh: None declared, Chuah Tyng Yu: None declared, Nur Emillia Roslan: None declared, Stanley Angkodjojo Speakers bureau: Boehringer Ingeilheim, Consultant of: Abbvie and DKSH, Kee Fong Phang: None declared, Thaschawee Arkachaisri: None declared, Melonie Sriranganathan: None declared, Teck Choon TAN: None declared, Peter Cheung Consultant of: Ad board for Boehringer Ingleheim, novartis, janssen and abbvie, Grant/research support from: Novartis, Manjari Lahiri Speakers bureau: J&J, DSKH, Consultant of: DSKH, Gilead, Grant/research support from: Multiple pharma companies contributed to the Singapore Biologics registry

Novartis

Protection of Toll-Like Receptor 9 Against Lipopolysaccharide-Induced Inflammation and Oxidative Stress of Pulmonary Epithelial Cells via MyD88-Mediated Pathways

Acute lung injury (ALI) caused by lipopolysaccharide (LPS) is a common, severe clinical syndrome. Injury caused by inflammation and oxidative stress in vascular endothelial and alveolar epithelial cells is a vital process in the pathogenesis of ALI. Toll-like receptor 9 (TLR9) is highly expressed in LPS-induced ALI rats. In this study, Beas-2B human pulmonary epithelial cells and A549 alveolar epithelial cells were stimulated by LPS, resulting in the upregulation of TLR9 in a concentration-dependent manner. Furthermore, TLR9 overexpression and interference vectors were transfected before LPS administration to explore the role of TLR9 in LPS-induced ALI in vitro. The findings revealed that inhibition of TLR9 reduced inflammation and oxidative stress while suppressing apoptosis of LPS-induced Beas-2B and A549 cells, whereas TLR9 overexpression aggravated these conditions. Moreover, TLR9 inhibition resulted in downregulated protein expression of myeloid differentiation protein 88 (MyD88) and activator activator protein 1 (AP-1), as well as phosphorylation of nuclear factor-B (NF-B), c-Jun N terminal kinase (JNK), and p38 mitogen-activated protein kinase (MAPK). The phosphorylation of extracellular-regulated protein kinases 1/2 was upregulated compared to that of cells subjected to only LPS administration, and this was reversed by TLR9 overexpression. These results indicate that inhibition of TLR9 plays a protective role against LPS-induced inflammation and oxidative stress in Beas-2B and A549 cells, possibly via the MyD88/NF-B and MyD88/MAPKs/AP-1 pathways.

The Antioxidant Role of Selenium via GPx1 and GPx4 in LPS-Induced Oxidative Stress in Bovine Endometrial Cells

This study investigated the antioxidant role of selenium (Se) in the form of selenomethionine (SLM) in LPS-induced oxidative stress via the glutathione peroxidase (GPx) enzymes and the Nrf2/HO-1 transcription factor. The impact of serum supplementation in culture media on GPxs was also studied. The bovine uterus is constantly exposed to exogenous pathogens postpartum, and the endometrium is the first contact against bacteria invasion. Endometritis is an inflammation of the endometrium and is brought about by bacterial lipopolysaccharide capable of inducing oxidative stress. The BEND cells were supplemented at the point of seeding with the following SLM concentrations 0, 100, 500, and 1000 nM for 48 h. BEND cells, cultured with or without SLM (100 nM), were initially incubated for 48 h, and then, we serum starved the SLM group for 24, 48, and 72 h. Similarly, an assay involving serum volume (0, 2, 5, and 10%) supplementation in culture media (v/v) with or without SLM (100 nM) was performed for 48 h. The BEND cells were also seeded into four experimental groups and cultured for an initial 48 h as follows: control, LPS (20 μg/mL), SLM (100 nM), and SLM + LPS groups followed by 6-h LPS treatment. The role of SLM in modulating the expressions of GPx1 and GPx4 and the Nrf2 transcription factor-related genes was assessed using qRT-PCR and Western blot techniques. The results showed serum starvation in the presence of SLM supplementation decreased the expression of GPx1 enzyme but increased GPx4 compared to the control. The addition of SLM to cell culture media in an FBS limiting condition improved the expressions of both GPx1 and GPx4. SLM supplementation promoted GPx enzymes' expressions in a serum-free media (0%) and at 2% FBS in media. However, it did not improve their expressions at 10% FBS in media than the untreated groups. Together, our data show the protective role of Se by regulating the expressions of GPx1 and GPx4 enzymes in BEND cells. It also shows that SLM promoted the expression of Nrf2 transcription factor-related genes at both the mRNA and protein levels in BEND cells during LPS stimulation.

A226 SEX-BASED DISPARITY COMPLICATIONS FOLLOWING LIVER TRANSPLANTATION

Background

Sex-based disparity exists in liver transplantation (LT) with women being disadvantaged at every stage of the process starting from assessment to post transplantation (Bryce et al., 2009). The reasons for this are multifactorial and include biological disparities, psychosocial, and allocation inequalities (Burra et al., 2013).

Aims

The purpose of this study was to identify differences in immediate or long-term complications post-LT by sex.

Methods

We analyzed 702 patients who underwent LT at the University of Alberta from 2002 to 2015. Patients aged < 18 years or requiring a repeat or multivisceral transplant were excluded. Renal dysfunction was defined according to the KDIGO criteria. Cardiovascular disease (CVD) was defined as hospitalization for or death from coronary artery disease, cardiac arrest or cerebrovascular disease.

Results

Male patients comprised 69% of the population. Time on the waitlist was similar for men (9.3 ± 11.7 months) and women (9.9 ± 12.3 months; p=0.57). Both sexes were comparable in age (males: 53 ± 10 years; females: 52 ± 11 years; p=0.19), MELD (males: 18 ± 9; females: 19 ± 10; p=0.16) and BMI (males: 27.7 ± 5.7 kg/m²; females: 27.3 ± 6.6 kg/m²; p=0.58). Women had lower creatinine pre-LT (males: 1.1 ± 0.60 mg/dL; females 0.96 ± 0.51 mg/dL; p<0.01). There were no differences in donor age, sex or BMI. Women had significantly longer hospital length of stay (males: 18 days [IQR: 11, 32]; females: 25 days [IQR: 14, 43]; p <0.001). There was no difference in risk of acute kidney injury (OR 1.4 [95% CI: 0.98, 2.1]; p=0.06), infection (OR 1.1 [95% CI: 0.8, 1.5]; p=0.52) or rejection episodes (OR 1.1 [95% CI: 0.8, 1.5]; p=0.74) following LT. Women had a higher risk of CKD post-LT (OR 2.3 [95% CI: 1.6, 3.2]; p<0.0001). There was no difference in de-novo diabetes (males: 22%; females: 16%; p=0.10), hypertension (males: 45%; females: 48%; p=0.41), dyslipidemia (males: 37%; females: 39%; p=0.67) and CVD (males: 20%; females: 19%; p=0.84) post-LT. Graft (males: 11.4 ± 0.4 years; females: 11.8 ± 0.5 years; p=0.32) and patient survival (males: 11.8 ± 0.4 years; females: 12.4 ± 0.5 years; p=0.18) were similar over a median follow up of 6.3 years [IQR: 3.5, 9.9].

Conclusions

Women spend a longer time in hospital and are at an increased risk of CKD following LT. Despite these differences, overall graft and patient survival are comparable. Our data suggest the disparity between sexes likely exists pre-LT and females that undergo LT have similar outcomes to their male counterparts.

Funding Agencies

None

A217 TREATMENT ADHERENCE OF CHRONIC HEPATITIS B PATIENTS WITH HEPATOCELLULAR CARCINOMA FROM THE CANHEPB NETWORK

Background

Chronic hepatitis B (CHB) is the most common cause of hepatocellular carcinoma (HCC) worldwide.

Aims

The primary aim of this study is to explore the degree of treatment adherence to the American Association For The Study of Liver Disease (AASLD) HCC treatment guidelines for patients with CHB-HCC.

Methods

This is a retrospective, cross-sectional study of available data (2005–2020) in patients mono-infected with CHB collected from the Canadian HBV Network; a national consortium across 8 Canadian provinces. We analyzed data using descriptive statistics along with parametric and nonparametric statistical methods with a significance level of p < 0.05.

Results

Of the 6500 patients, 132 (2.0%) patients met inclusion criteria. The median age was 64 (IQR: 53.5- 71.5) with 101 (76%) being male. The median ALT was 40 (IQR: 26–59.5) and the median tumor number was 1(IQR: 1- 2) with a median tumor size of 2.6 cm (IQR: 1.9- 4.5). 98 (74.5%) patients were HBeAg negative with a median viral load of 3.8 logs (IQR 1.9 – 5.8). 58 (43%) patients had cirrhosis at diagnosis. 36% of patients were diagnosed with HCC on their first screening imaging whereas 39% were found to have HCC on repeated surveillance imaging. 116 (87.9%) were on treatment at the time of diagnosis or after (70 (60.3%) NA and 46 (39%) Combination therapy with double NA or NA plus interferon). Out of the 132 patients, BCLC stage 0, A, B, and C represented 30 (23%), 42 (32%), 17 (13%), and 5 (4%) patients, respectively, with 38 (28%) patients with unknown BCLC stage. The overall adherence to AASLD guidelines was 61%. The HCC treatment adherence rate for patients with BCLC stage 0, A, B were 63%, 97.5%, and 23.5%, respectively. BCLC stages C and D did not have a sufficient sample size for analysis. The adherence rate ranged from 53% (Eastern Canada) to 71% (Western Canada) across Canada.

Conclusions

In this retrospective nationwide cohort study of patients with CHB-related HCC, the overall treatment adherence rate to AASLD guidelines was low with notable regional differences. Further analysis will determine the cause of regional differences.

Funding Agencies

None