A novel, small anti-HBV compound reduces HBsAg and HBV-DNA by destabilizing HBV-RNA.

BACKGROUND: Currently, standard treatments for chronic hepatitis B such as nucleos(t)ide analogs (NAs), effectively reduce hepatitis B virus (HBV) loads but rarely result in a functional cure (defined as sustained HBsAg loss). We report the discovery of a novel, 4-pyridone compound, SAG-524, a potent and orally bioavailable small molecule inhibitor of HBV replication. METHODS: The antiviral characteristics and selectivity of SAG-524 and its derivative compound against HBV were evaluated in HBV-infection assays and HBV-infected chimeric urokinase-type plasminogen activator/severe combined immunodeficiency mice with humanized livers (PXB mice), alone or in combination with entecavir. Toxicity studies were conducted in mice and monkeys. RESULTS: SAG-524 reduced HBV-DNA (IC50 = 0.92 nM) and HBsAg (IC50 = 1.4 nM) in the supernatant of the HepG2.2.15 cells. SAG-524 selectively destabilized HBV-RNA via PAPD5, but not GAPDH or albumin mRNA, by shortening the poly(A) tail. PAPD5 may also be involved in HBV regulation via ELAVL1. In a study of HBV-infected PXB mice, SAG-524 produced potent reductions of serum HBsAg and HBcrAg, and the minimum effective dose was estimated to be 6 mg/kg/day. The combination therapy with entecavir greatly reduced HBsAg and cccDNA in the liver due to reduction of human hepatocytes with good tolerability. Administration of SAG-524 to monkeys, up to 1000 mg/kg/day for two weeks, led to no significant toxicity, as determined by blood tests and pathological images. CONCLUSIONS: We have identified SAG-524 as novel and orally bioavailable HBV-RNA destabilizers which can reduce HBsAg and HBV-DNA levels, and possibly contribute a functional cure.

Randomized phase I/II study of vascular endothelial growth factor receptor peptide vaccines for patients with hepatocellular carcinoma.

AIM: We evaluated the safety and efficacy of vascular endothelial growth factor receptor (VEGFR)-targeted peptide vaccines for the immunization of patients with unresectable hepatocellular carcinoma (HCC) who had responded to transarterial chemoembolization. METHODS: Twenty-two patients were randomized 1:1 to receive VEGFR-targeted peptides or placebo. The primary end-point was the safety assessment of the immunization. The secondary end-points were evaluation of immunological responses and clinical outcomes. RESULTS: No severe adverse events were induced by the study agents. Among the 12 patients in the vaccine group, a VEGFR1-specific cytotoxic T lymphocyte (CTL) response was induced in eight (66.7%) patients and a VEGFR2-specific CTL response was induced in 10 (83.3%). The median progression-free survival (PFS) and overall survival (OS) rates were 4.8 and 52.0 months, respectively, in the vaccine group, and 2.7 and 21.8 months, respectively, in the placebo group. No statistically significant differences were found between the two groups (PFS p = 0.925, OS p = 0.190). When divided into two groups according to immunoreactivity, the median PFS of patients with and without a strong immune response to VEGFR1 were 7.4 and 2.7 months, and that to VEGFR2 were 10.6 and 2.7 months, respectively; there were significant differences according to the immune response. CONCLUSIONS: Immunotherapy with peptide vaccines targeting VEGFR1 and VEGFR2 was well tolerated with no serious adverse events. It also effectively induced peptide-specific CTLs in patients with unresectable HCC.

Therapeutic Modifications without Discontinuation of Atezolizumab Plus Bevacizumab Therapy Are Associated with Favorable Overall Survival and Time to Progression in Patients with Unresectable Hepatocellular Carcinoma.

We retrospectively evaluated the impact of therapeutic modifications of atezolizumab (Atezo) plus bevacizumab (Bev) therapy (Atezo/Bev), including the interruption or discontinuation of both Atezo and Bev, and the reduction or discontinuation of Bev, on the outcome of patients with unresectable hepatocellular carcinoma (uHCC) (median observation period: 9.40 months). One hundred uHCC from five hospitals were included. Therapeutic modifications without discontinuation of both Atezo and Bev (n = 46) were associated with favorable overall survival (median not reached; hazard ratio (HR): 0.23) and time to progression (median: 10.00 months; HR: 0.23) with no therapeutic modification defined as the reference. In contrast, the discontinuation of both Atezo and Bev without other therapeutic modifications (n = 20) was associated with unfavorable overall survival (median: 9.63 months; HR: 2.72) and time to progression (median: 2.53 months; HR: 2.78). Patients with modified albumin-bilirubin grade 2b liver function (n = 43) or immune-related adverse events (irAEs) (n = 31) discontinued both Atezo and Bev without other therapeutic modifications more frequently (30.2% and 35.5%, respectively) than those with modified albumin-bilirubin grade 1 (10.2%) and without irAEs (13.0%). Patients with objective response (n = 48) experienced irAEs more frequently (n = 21) than those without (n = 10) (p = 0.027). Avoiding the discontinuation of both Atezo and Bev without other therapeutic modifications may be the optimal management of uHCC.

Optimal management of lenvatinib therapy for patients with unresectable hepatocellular carcinoma by balancing the therapeutic effect with the relative dose intensity.

AIMS: We aimed to assess the optimal management of first or later-line lenvatinib therapy (LEN) for patients with unresectable hepatocellular carcinoma (uHCC), by clarifying the difference of degree between relative dose intensity (RDI) to achieve objective response (OR) and disease control (DC) by aiming at stable disease (SD), taking dose modifications into consideration. METHODS: One hundred uHCC patients who received LEN in first- or later-line settings, between April 2018 and December 2020 in our hospital were analyzed retrospectively. The factors associated with overall survival (OS), time to progression (TTP), OR and DC were assessed. The optimal cut-off values of RDI 4 weeks after initiation of LEN (RDI during cycle 1) and total RDI (RDI during all cycles) to predict achievement of OR and DC by aiming at SD were determined by receiver operator curve analysis. RESULTS: Achievement of OR and SD were favorable factors for OS (HR, 0.080 and 0.20) and TTP (HR, 0.052 and 0.073), with progressive disease defined as the reference. RDI ≥ 0.8 during cycle 1 and RDI ≥ 0.4 during cycle 1 contributed to achievement of OR (odds ratio, 3.28) and DC (odds ratio, 4.85), respectively. Experience of dose interruption was associated with a favorable TTP (HR, 0.58). The therapeutic line of LEN did not contribute to OS, TTP or best response. CONCLUSIONS: To achieve OR and SD for a favorable outcome of first- or later-line LEN, high and moderate early-phase RDI are required, respectively. The degree of RDI during LEN and tolerance need compatible by dose modifications.

Improved indocyanine green retention after short-term lenvatinib withdrawal in three patients with hepatocellular carcinoma.

Use of lenvatinib, which has a high response rate in advanced hepatocellular carcinoma, sometimes results in tumor shrinkage and resectability of previously unresectable liver cancers. In Asia, including Japan, liver reserve, one of the determinants of resectability, is mainly determined by the indocyanine green (ICG) retention rate. Three patients with advanced liver cancer treated at our institution had very poor ICG retention rates during treatment with lenvatinib. Lenvatinib may reduce blood flow in both cancerous and non-cancerous regions by inhibiting vascular endothelial growth factor. Therefore, accurate determination of liver function likely requires withdrawal of this treatment several days before ICG retention testing.

Direct reprogramming of human umbilical vein- and peripheral blood-derived endothelial cells into hepatic progenitor cells.

Recent advances have enabled the direct induction of human tissue-specific stem and progenitor cells from differentiated somatic cells. However, it is not known whether human hepatic progenitor cells (hHepPCs) can be generated from other cell types by direct lineage reprogramming with defined transcription factors. Here, we show that a set of three transcription factors, FOXA3, HNF1A, and HNF6, can induce human umbilical vein endothelial cells to directly acquire the properties of hHepPCs. These induced hHepPCs (hiHepPCs) propagate in long-term monolayer culture and differentiate into functional hepatocytes and cholangiocytes by forming cell aggregates and cystic epithelial spheroids, respectively, under three-dimensional culture conditions. After transplantation, hiHepPC-derived hepatocytes and cholangiocytes reconstitute damaged liver tissues and support hepatic function. The defined transcription factors also induce hiHepPCs from endothelial cells circulating in adult human peripheral blood. These expandable and bipotential hiHepPCs may be useful in the study and treatment of human liver diseases.

Risk factors for de novo hepatitis B during solid cancer treatment.

BACKGROUND: Reactivation of hepatitis B virus (HBV) during anticancer treatment is a critical issue. When treating patients with solid tumors, it is unclear whether specific cancer types or treatments affect HBV reactivation in hepatitis B surface antigen (HBsAg)-negative and hepatitis B core antibody (HBcAb)-positive patients, so-called de novo hepatitis B patients. The risk of de novo hepatitis B may vary based on different background factors. AIM: To determine the frequency and risk factors for de novo hepatitis B during solid tumor treatment. METHODS: This retrospective cohort study comprised 1040 patients without HBsAgs and with HBcAbs and/or hepatitis B surface antibodies (HBsAbs). The patients were treated for solid cancer from 2008 to 2018 at the National Kyushu Cancer Center and underwent HBV DNA measurements. Patient characteristics and disease and treatment information were investigated. HBV DNA measurements were performed using TaqMan polymerase chain reaction (PCR). To identify the risk factors associated with HBV DNA expression, the age, sex, original disease, pathology, treatment method, presence or absence of hepatitis C virus (HCV), and HBsAb and/or HBcAb titers of all subjects were investigated. In patients with HBV DNA, the time of appearance, presence of HBsAgs and HBsAbs at the time of appearance, and course of the subsequent fluctuations in virus levels were also investigated. RESULTS: Among the 1040 patients, 938 were HBcAb positive, and 102 were HBcAb negative and HBsAb positive. HBV DNA expression was observed before the onset of treatment in nine patients (0.9%) and after treatment in 35 patients (3.7%), all of whom were HBcAb positive. The HBV reactivation group showed significantly higher median HBcAb values [9.00 (8.12-9.89) vs 7.22 (7.02-7.43), P = 0.0001] and significantly lower HBsAb values (14 vs 46, P = 0.0342) than the group without reactivation. Notably, the reactivated group showed a significantly higher proportion of cancers in organs related to digestion and absorption (79.0% vs 58.7%, P = 0.0051). A high HBcAb titer and cancers in organs involved in digestion and absorption were identified as independent factors for HBV reactivation (multivariate analysis, P = 0.0002 and P = 0.0095). The group without HBsAbs tended to have a shorter time to reactivation (day 43 vs day 193), and the frequency of reactivation within 6 mo was significantly higher in this group (P = 0.0459) than in the other group. CONCLUSION: A high HBcAb titer and cancers in organs involved in digestion and absorption are independent factors that contribute to HBV reactivation during solid tumor treatment.