Targeted Extracellular Vesicles Delivered Verrucarin A to Treat Glioblastoma

Glioblastomas, accounting for approximately 50% of gliomas, comprise the most aggressive, highly heterogeneous, and malignant brain tumors. The objective of this study was to develop and evaluate a new targeted therapy, i.e., highly potent natural compound verrucarin A (Ver-A), delivered with monoclonal antibody-directed extracellular vesicle (mAb-EV). First, the high surface expression of epidermal growth factor receptor (EGFR) in glioblastoma patient tissue and cell lines was confirmed using immunohistochemistry staining, flow cytometry, and Western blotting. mAb-EV-Ver-A was constructed by packing Ver-A and tagging anti-EGFR mAb to EV generated from HEK293F culture. Confocal microscopy and the In Vivo Imaging System demonstrated that mAb-EV could penetrate the blood–brain barrier, target intracranial glioblastoma xenografts, and deliver drug intracellularly. The in vitro cytotoxicity study showed IC50 values of 2–12 nM of Ver-A. The hematoxylin and eosin staining of major organs in the tolerated dose study indicated minimal systemic toxicity of mAb-EV-Ver-A. Finally, the in vivo anti-tumor efficacy study in intracranial xenograft models demonstrated that EGFR mAb-EV-Ver-A effectively inhibited glioblastoma growth, but the combination with VEGF mAb did not improve the therapeutic efficacy. This study suggested that mAb-EV is an effective drug delivery vehicle and natural Ver-A has great potential to treat glioblastoma.

Toxicological safety of VOHO Hemp Oil; a supercritical fluid extract from the aerial parts of hemp

VOHO Hemp Oil (Verdant Nature LLC (in collaboration with HempFusion)) is an extract of the aerial parts of hemp (Cannabis sativa L) manufactured using a supercritical CO2 extraction process. The results of four safety studies are reported here including a bacterial reverse mutation assay, an in vivo mammalian micronucleus study, a maximum tolerated dose study in rats and a 90-day repeat dose subchronic toxicity study in rats. VOHO Hemp oil can contain up to 30% phytocannabinoids and less than 0.2% is tetrahydrocannabinol (THC). VOHO Hemp Oil was found to be non-mutagenic in the bacterial reverse mutation assay and was negative for inducing micronuclei in the rat bone marrow micronucleus assay. The maximum tolerated dose in male and female Wistar rats was 2250 mg/kg bw/day. A 90-day repeat dose study was conducted in male and female Wistar rats according to OECD Guideline 408 and included a 21-day recovery period. The doses used in the study were 0, 25, 90 and 324 mg/kg bw per day in the main study, and in the recovery phase a control and 324 mg/kg bw/day group were included. One mortality was reported during the study, a high dose female, and test substance-related adverse clinical signs were reported in the high dose group. Other test substance-related changes noted in the high dose group included changes in body weights, activated partial thromboplastin time (APTT) values, and in absolute and relative organ weights. Based on the results of the study, the no observed adverse effect level (NOAEL) for VOHO Hemp Oil was determined to be 90 mg/kg bw/day in both male and female Wistar rats.

The Differences in the Level of Anti-SARS-CoV-2 Antibodies after mRNA Vaccine between Convalescent and Non-Previously Infected People Disappear after the Second Dose—Study in Healthcare Workers Group in Poland

(1) Background: In many infections, antibodies play a crucial role in controlling infection. In COVID-19, the dynamics of the immune system response to SARS-CoV-2 is not fully understood. (2) Methods: The study was conducted on 120 healthcare workers from Dr. Antoni Jurasz University Hospital No. 1 in Bydgoszcz, between June and December 2020. In all participants, IgA and IgG antibody serum concentrations were measured using the semi-quantitative Anti-SARS-CoV-2 ELISA test (Euroimmun). After vaccination, in January and February 2021, antibody levels were examined using the quantitative IgG Anti-SARS-CoV-2 Quantivac ELISA test (Euroimmun). (3) Results: During the whole study period, the SARS-CoV-2 infection was confirmed in 29 (24.2%) participants. In all infected participants, IgA and IgG antibodies were detectable after infection by semi-quantitative serological tests. Levels of antibodies were higher one month after the first dose in the convalescents than in the non-previously infected participants. In this second group, the level of antibodies increased significantly after the second dose of vaccines compared to the first dose. (4) Conclusions: The level of antibodies after the first dose of vaccine in the convalescents’ group is higher than in the SARS-CoV-2 non-infected group, but the differences disappear after the second vaccination.

Efanesoctocog alfa for hemophilia A: results from a phase 1 repeat-dose study

Efanesoctocog alfa (rFVIIIFc-VWF-XTEN, BIVV001) is a new class of factor VIII (FVIII) replacement that breaks the von Willebrand factor-imposed FVIII half-life ceiling. In a Phase 1/2a study, single-dose efanesoctocog alfa was well tolerated and no safety concerns were identified. We evaluated the safety, tolerability, and pharmacokinetics of repeat-dose efanesoctocog alfa in a Phase 1 study in previously treated adults (≥150 exposure days) with severe hemophilia A. Participants received four once-weekly efanesoctocog alfa doses (Cohort 1, 50 IU/kg; Cohort 2, 65 IU/kg). All enrolled participants (Cohort 1, n=10; Cohort 2, n=14) completed the study. Inhibitor development to FVIII was not detected. After the last efanesoctocog alfa dose, geometric mean (range) FVIII activity half-life, area under the activity-time curve, and steady state maximum concentration for Cohort 1 and Cohort 2 were 41.3 (34.2-50.1) hours and 37.3 (28.9-43.8) hours, 8290 (5810-10,300) h × IU/dL and 11,200 (7040-15,800) h × IU/dL, and 131 (96-191) IU/dL and 171 (118-211) IU/dL, respectively. There was minimal accumulation after 4 doses. Mean FVIII activity on Day 3 post dose was 46% and 69% and on Day 7 was 10% and 12% for Cohorts 1 and 2, respectively. Overall, four once-weekly doses of efanesoctocog alfa were well tolerated, no safety concerns identified, and no bleeds reported during the treatment period. Once-weekly efanesoctocog alfa provided high sustained FVIII activity within the normal to near-normal range for 3-4 days post-dose and may improve protection against bleeds in patients with hemophilia A. (EU Clinical Trials Register study 2018-001535-51)

1099. Evaluation of the Safety and Pharmacokinetics (PK) following Administration of Single and Multiple Doses of Anti-Staphylococcal Lysin, LSVT-1701, in Healthy Adult Subjects

Background LSVT-1701 is an anti-staphylococcal phage lysin being developed for treatment of MRSA infections in combination with SoC antibiotics. The safety and PK of single ascending doses of LSVT-1701 0.1 to 10 mg/kg in healthy adult volunteers were previously described (Jun, et.al, AAC 2017;61:e02629-16). We further evaluated the safety and PK of multiple ascending doses of LSVT-1701 in healthy adult subjects. Methods Study ITB-101-1b was a Phase 1, randomized, double-blind, placebo-controlled, multiple ascending dose study. 8 subjects were randomized 3:1 to active:placebo in each cohort. LSVT-1701 was administered as a 6 mg/kg single dose and twice daily (BID) doses of 1.5, 3.0, and 4.5 mg/kg for 4 days (24h between Doses 1-2, 12h between Doses 2-6). Study drugs were administered as a 1-hour IV infusion. Serial serum samples were collected over 24 hours following the first and last doses for measurement of LSVT-1701 concentrations by a validated ELISA method. PK analysis of LSVT-1701 concentration-time data was done using noncompartmental methods. Safety was assessed by AEs, clinical labs, vital signs, and ECG. Results 30/32 (94%) subjects completed the study. No subjects withdrew due to AEs, and there were no severe AEs, no serious AEs, and no deaths. AEs were of mild (97%) to moderate (3%) intensity and were reported by all subjects in the LSVT-1701 6 mg/kg single dose group and 1-3 (17-50%) of subjects receiving 1.5 to 4.5 mg/kg BID or placebo. The most common AEs of headache, chills, rigors, and fever generally lasted for ≤2 days with or without acetaminophen treatment, and no clinically significant changes in blood pressure, heart rate, ECG, or clinical labs (other than transient increases in CRP) were observed. Infusion site reactions (erythema, pain, induration, warmth) were observed with BID administration of LSVT-1701, but not with the single 6 mg/kg dose or placebo. LSVT-1701 exposure increased greater than in proportion to dose and t1/2 was concentration-dependent, increasing with higher doses. No accumulation in LSVT-1701 exposure was observed. Summary of LSVT-1701 PK Parameters Summary of LSVT-1701 PK Parameters Conclusion The safety and PK profile of LSVT-1701 is favorable for evaluation in patients with S. aureus infections, including bacteremia and infective endocarditis, for which new treatments are needed. Disclosures Mary Beth Wire, Pharm#, Lysovant (Consultant) Soo youn Jun, PhD, iNtRON Biotechnology (Consultant) In-Jin Jany, PhD, iNtRON (Consultant) Jun Gi Hwang, PhD, Lysovant (Consultant) David Huang, MD, PhD, Lysovant (Consultant)