A randomized phase 2b study of subcutaneous PD-L1 antibody ASC22 in virally-suppressed, HBeAg negative chronic hepatitis B patients.

BACKGROUND AIMS: Studies have shown that blocking the PD-1/PD-L1 pathway may lead to a potential cure for HBV infections. ASC22 (Envafolimab) is a humanized, single-domain PD-L1 antibody administered subcutaneously. This study aimed to evaluate the efficacy and safety of ASC22 in virally suppressed chronic hepatitis B (CHB) patients on nucleos(t)ide analogs (NAs). APPROACH AND RESULTS: This randomized, single-blind, phase IIb trial enrolled CHB patients in two cohorts for a 24-week treatment with ASC22 or placebo (PBO) once every 2 weeks and 24-week follow-up. In total, 60, 59, and 30 patients were treated with 1.0, 2.5 mg/kg ASC22 and PBO, respectively. The mean HBsAg changes from baseline at week 24 and 24 week follow-up periods were -0.309 (p<0.001) and -0.272 (p<0.023) log10 IU/mL in the 1.0 mg/kg ASC22 group, -0.231 (p=0.007) and -0.205 (p=0.12) log10 IU/mL in the 2.5 mg/kg ASC22 group, and-0.003 and -0.063 log10 IU/mL in the PBO group, respectively (ITT population). Three out of ten patients with baseline HBsAg levels ≤100 IU/mL in the 1.0 mg/kg group obtained on-treatment HBsAg loss. Most AEs were mild (97.9%). There were no study drug-related serious AEs in the 1.0 mg/kg ASC22 group. CONCLUSIONS: Subcutaneous administration of 1.0 mg/kg ASC22 Q2W for 24 weeks was shown to be safe and well tolerated in virally suppressed CHB patients on NAs and can induce HBsAg decline, especially in patients with HBsAg ≤100 IU/mL.

Twelve-week ravidasvir plus ritonavir-boosted danoprevir and ribavirin for non-cirrhotic HCV genotype 1 patients: A phase 2 study.

BACKGROUND AND AIM: The need for all-oral hepatitis C virus (HCV) treatments with higher response rates, improved tolerability, and lower pill burden compared with interferon-inclusive regimen has led to the development of new direct-acting antiviral agents. Ravidasvir (RDV) is a second-generation, pan-genotypic NS5A inhibitor with high barrier to resistance. The aim of this phase 2 study (EVEREST study) was to assess the efficacy and safety of interferon-free, 12-week RDV plus ritonavir-boosted danoprevir (DNVr) and ribavirin (RBV) regimen for treatment-naïve Asian HCV genotype 1 (GT1) patients without cirrhosis. METHODS: A total of 38 treatment-naïve, non-cirrhotic adult HCV GT1 patients were enrolled in this multicenter, open-label, single-arm phase 2 study (NCT03020095). All patients received a combination of RDV 200 mg once daily (q.d.) plus DNVr 100 mg/100 mg twice daily (b.i.d.) and oral RBV 1000/1200 mg/day (body weight < 75/≥ 75 kg) for 12 weeks. The primary endpoint was the rate of sustained virologic response 12 weeks after the end of treatment (SVR12). RESULTS: Of 38 patients, all (100%) achieved SVR12. During the study, no treatment-related serious adverse events, no patients discontinued treatment due to adverse events, and no deaths were reported. Six of 37 (16%) patients with available sequences had HCV NS5A resistance-associated variants at baseline. All patients (6/6) with baseline NS5A resistance-associated variants achieved SVR12. CONCLUSIONS: Twelve-week RDV and DNVr in combination with RBV for 12 weeks achieves the SVR12 rate of 100% in treatment-naïve non-cirrhotic Asian patients with HCV GT1 infection. This interferon-free regimen is also safe and well tolerated.

Pyridoxine hydroxamic acids as novel HIV-integrase inhibitors.

A series of pyridoxine hydroxamic acid analog bearing a 5-aryl-spacers were synthesized. Evaluation of these novel HIV integrase complex inhibitors revealed compounds with high potency against wild-type HIV virus.

Ritonavir-boosted danoprevir plus peginterferon alfa-2a and ribavirin in Asian chronic hepatitis C patients with or without cirrhosis.

BACKGROUND AND AIM: Chronic hepatitis C is an important public health problem in Asia. We evaluated the safety, efficacy, and pharmacokinetics of fixed-dose ritonavir-boosted danoprevir plus peginterferon alfa-2a/ribavirin in treatment-naive Asian patients with chronic hepatitis C virus (HCV) genotype (G)1 infection. METHODS: Treatment-naive G1 patients in Taiwan, Thailand, and Korea with serum HCV-RNA level ≥ 105 IU/mL received ritonavir-boosted danoprevir 125/100 mg twice daily plus peginterferon alfa-2a/ribavirin for either 12 (noncirrhotic patients: Arm A, n = 34) or 24 weeks (cirrhotic patients: Arm B, n = 27) in this phase II open-label study. Sustained virologic response was defined as HCV-RNA < 25 IU/mL 12 weeks after end of treatment (SVR12). RESULTS: Similar SVR12 rates were achieved in Arms A (88.2%; 95% confidence interval, 73.4-95.3%) and B (88.9%; 71.9-96.2%). Most patients had G1b infection, among whom SVR12 rates in Arms A and B were 96.7% and 91.7%, respectively. The overall SVR12 rate was 94.0% in noncirrhotic Taiwanese patients (100% in the subset of G1b patients). No patients withdrew for safety reasons. Three (11%) cirrhotic patients (Arm B) experienced serious adverse events, none of which was considered to be related to treatment. No Grade 3/4 alanine aminotransferase elevations were reported. The pharmacokinetic properties of danoprevir were broadly overlapping in noncirrhotic and cirrhotic patients both on Days 1 and 14. CONCLUSIONS: Ritonavir-boosted danoprevir plus peginterferon alfa-2a/ribavirin produced sustained virologic response rates > 90% after 12 weeks' treatment in noncirrhotic and 24 weeks' treatment in cirrhotic Asian patients with G1b infection and was well tolerated. These regimens are well suited to countries where G1b predominates.

Safety, tolerability and pharmacokinetics of ASC10, a novel oral double prodrug of a broad-spectrum antiviral agent, ß-d-N4-hydroxycytidine: results from a randomized, double-blind, placebo-controlled phase 1 study in Chinese healthy subjects.

BACKGROUND: Considering the rise of new SARS-CoV-2 variants that have reduced the efficacy of COVID-19 vaccines, the development of new antiviral medications for the disease has become increasingly necessary. In this study, ASC10, a novel antiviral prodrug, was studied in a phase 1 trial in healthy Chinese participants. RESEARCH DESIGN AND METHODS: Part 1 involved 60 participants, receiving 50-800 mg ASC10 or placebo twice daily for 5.5 days. Part 2, with 12 participants, explored ASC10 dosing in the fed/fasting states. RESULTS: ASC10-A, the main pharmacologically active metabolite, rapidly appeared in plasma (Tmax: 1.00-2.00 h) and decreased (t1/2: 1.10-3.04 h) without accumulation. The Cmax and area under the plasma concentration - time curve (AUC) of ASC10-A increased dose-dependently (50-800 mg BID) over 5.5 days, with no accumulation. The Tmax was slightly delayed in the fed state; however, the Cmax and AUC were similar between the fed and fasting states. Adverse events (AEs) were comparable (ASC10/placebo, 66.7%) and mostly mild (95%). CONCLUSION: ASC10 was demonstrated to be safe and well tolerated and exhibited dose-proportional exposure and minimal food effects. CLINICAL TRIAL REGISTRATION: www.clinicaltrials.gov identifier is NCT05523141.

Human Safety, Tolerability, Pharmacokinetics, and Pharmacodynamics of ASC42, a Novel Farnesoid X Receptor Agonist.

BACKGROUND: ASC42 is a non-steroidal farnesoid X receptor agonist currently in clinical development for chronic liver diseases, such as nonalcoholic fatty liver disease/nonalcoholic steatohepatitis (NAFLD/NASH) and primary biliary cirrhosis (PBC). OBJECTIVE: The objective of this study was to assess the safety, pharmacokinetics (PK), and pharmacodynamics (PD) of ASC42 in healthy subjects. METHODS: We conducted the first-in-human study of ASC42 following single and multiple ascending doses (SAD/MAD) and food effect in healthy subjects. The SAD study included five cohorts receiving 5-200 mg ASC42 or placebo and one cohort that was given 15 mg ASC42 with a high-fat meal. The MAD study included three cohorts receiving 5-50 mg ASC42 or placebo once-daily (QD) for 14 days. RESULTS: A total of 65 healthy subjects were enrolled and one subject in the MAD study (cohort 8, ASC42 50 mg) withdrew from the study due to an unrelated serious adverse event (SAE) of atrial fibrillation. Pruritus was observed at the highest doses (200 mg cohort in SAD and 50 mg cohort in MAD). Most AEs were mild or moderate. No life-threatening or fatal AEs occurred. ASC42 showed a proportional increase in exposure and elimination half-life following both single and multiple dosing. There was a 21% and 37% decrease in area under the curve (AUC) and maximum plasma concentration (Cmax) when ASC42 was coadministered with food. The steady state was reached on day 4 with a mild accumulation (1.02-1.74-fold). ASC42 showed dose-dependent increases in fibroblast growth factor 19 and decreases in 7α-hydroxy-4-cholesten-3-one. Cholesterol remained within normal limits during study. CONCLUSION: ASC42 was well tolerated with a pharmacokinetic profile suitable for QD dosing, and demonstrated dose-dependent targets engagement without altering plasma cholesterol in healthy subjects. TRIAL REGISTRATION NUMBER: NCT04679129.

Nanoparticles targeted with NGR motif deliver c-myc siRNA and doxorubicin for anticancer therapy.

We have designed a PEGylated LPD (liposome-polycation-DNA) nanoparticle for systemic, specific, and efficient delivery of small interfering RNA (siRNA) into solid tumors in mice by modification with NGR (aspargine-glycine-arginine) peptide, targeting aminopeptidase N (CD13) expressed in the tumor cells or tumor vascular endothelium. LPD-PEG-NGR efficiently delivered siRNA to the cytoplasm and downregulated the target gene in the HT-1080 cells but not CD13(-) HT-29 cells, whereas nanoparticles containing a control peptide, LPD-PEG-ARA, showed only little siRNA uptake and gene silencing activity. LPD-PEG-NGR efficiently delivered siRNA into the cytoplasm of HT-1080 xenograft tumor 4 hours after intravenous injection. Three daily injections (1.2 mg/kg) of c-myc siRNA formulated in the LPD-PEG-NGR effectively suppressed c-myc expression and triggered cellular apoptosis in the tumor, resulting in a partial tumor growth inhibition. When doxorubicin (DOX) and siRNA were co-formulated in LPD-PEG-NGR, an enhanced therapeutic effect was observed.

Long-term positive severe acute respiratory syndrome coronavirus 2 ribonucleic acid and therapeutic effect of antivirals in patients with coronavirus disease: Case reports.

Coronavirus disease (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has been declared a pandemic. We herein report four COVID-19 cases with long-term positive viral ribonucleic acid (RNA) for about 61 days. Despite treatment with recombinant human interferon, convalescent plasma from COVID-19 patients, arbidol, etc., nucleic acid results were still positive for SARS-CoV-2. After treatment with ritonavir-boosted danoprevir (DNVr, 100/100 mg, once daily), all four patients showed two to three consecutive negative SARS-CoV-2 RNA and were thus discharged from hospital. Therefore, DNVr may be a potentially effective antiviral for COVID-19 patients with long-term positive SARS-CoV-2 RNA.

First clinical study using HCV protease inhibitor danoprevir to treat COVID-19 patients.

INTRODUCTION: As coronavirus disease 2019 (COVID-19) outbreak globally, repurposing approved drugs is emerging as important therapeutic options. Danoprevir boosted by ritonavir (Ganovo) is a potent hepatitis C virus (HCV) protease (NS3/4A) inhibitor, which was approved and marketed in China since 2018 to treat chronic hepatitis C patients. METHODS: This is an open-label, single arm study evaluating the effects of danoprevir boosted by ritonavir on treatment naïve and experienced COVID-19 patients for the first time. Patients received danoprevir boosted by ritonavir (100 mg/100 mg, twice per day). The primary endpoint was the rate of composite adverse outcomes and efficacy was also evaluated. RESULTS: The data showed that danoprevir boosted by ritonavir is safe and well tolerated in all patients. No patient had composite adverse outcomes during this study. After initiation of danoprevir/ritonavir treatment, the first negative reverse real-time PCR (RT-PCR) test occurred at a median of 2 days, ranging from 1 to 8 days, and the obvious absorption in CT scans occurred at a median 3 days, ranging from 2 to 4 days. After 4 to 12-day treatment of danoprevir boosted by ritonavir, all enrolled 11 patients were discharged from the hospital. CONCLUSION: Our findings suggest that repurposing danoprevir for COVID-19 is a promising therapeutic option.

Enhanced antitumor efficacy of clinical-grade vasculature-targeted liposomal doxorubicin.

PURPOSE: In vivo evaluation of good manufacturing practice-grade targeted liposomal doxorubicin (TVT-DOX), bound to a CD13 isoform expressed on the vasculature of solid tumors, in human tumor xenografts of neuroblastoma, ovarian cancer, and lung cancer. EXPERIMENTAL DESIGN: Mice were implanted with lung, ovarian, or neuroblastoma tumor cells via the pulmonary, peritoneal, or orthotopic (adrenal gland) routes, respectively, and treated, at different days post inoculation, with multiple doses of doxorubicin, administered either free or encapsulated in untargeted liposomes (Caelyx) or in TVT-DOX. The effect of TVT-DOX treatment on tumor cell proliferation, viability, apoptosis, and angiogenesis was studied by immunohistochemical analyses of neoplastic tissues and using the chick embryo chorioallantoic membrane assay. RESULTS: Compared with the three control groups (no doxorubicin, free doxorubicin, or Caelyx), statistically significant improvements in survival was seen in all three animal models following treatment with 5 mg/kg (maximum tolerated dose) of TVT-DOX, with long-term survivors occurring in the neuroblastoma group; increased survival was also seen at a dose of 1.7 mg/kg in mice bearing neuroblastoma or ovarian cancer. Minimal residual disease after surgical removal of neuroblastoma primary mass, and the enhanced response to TVT-DOX, was visualized and quantified by bioluminescence imaging and with magnetic resonance imaging. When treated with TVT-DOX, compared with Caelyx, all three tumor models, as assayed by immunohistochemistry and chorioallantoic membrane, showed statistically significant reductions in cell proliferation, blood vessel density, and microvessel area, showing increased cell apoptosis. CONCLUSION: TVT-DOX should be evaluated as a novel angiostatic strategy for adjuvant therapy of solid tumors.