A Phase 3, Randomized, Open-label, Noninferiority Trial Evaluating Anti-Rabies Monoclonal Antibody Cocktail (TwinrabTM) Against Human Rabies Immunoglobulin (HRIG)

2020 ◽  
Author(s):  
Kevinkumar Kansagra ◽  
Deven Parmar ◽  
Sanjeev Kumar Mendiratta ◽  
Jatin Patel ◽  
Shuchi Joshi ◽  
...  
Keyword(s):  
Monoclonal Antibody ◽  
Neutralizing Antibodies ◽  
Geometric Mean ◽  
World Health ◽  
Human Rabies ◽  
Open Label ◽  
Phase 3 ◽  
Noninferiority Trial ◽  
Rabid Animal ◽  
Antibody Cocktail

Abstract Background Limited supply, cost and potential for severe adverse effects observed with the blood derived rabies immunoglobulin products has led to search for alternative therapies. This issue has been addressed by developing an anti-rabies monoclonal antibody cocktail. Methods This is a phase 3, randomized, open-label, noninferiority trial conducted in patients with World Health Organization (WHO) category III exposure with suspected rabid animal. Eligible patients were assigned to either the test arm, TwinrabTM (docaravimab and miromavimab) or the reference arm, human rabies immunoglobulin (HRIG; Imogam® Rabies-HT), in a ratio of 1:1. The primary endpoint was the comparison of responder rates between the 2 arms assessed as percentage of those with rabies virus neutralizing antibodies titers ≥0.5 IU/mL on day 14. Results A total of 308 patients were equally randomized into the 2 arms. In the per-protocol (PP) population, there were 90.21% responders in the TwinrabTM arm and 94.37% in the HRIG arm. The geometric mean of rapid fluorescent foci inhibition test titers in the PP on day 14 were 4.38 and 4.85 IU/mL, for the TwinrabTM and HRIG arms, respectively. There were no deaths or serious adverse events reported. Conclusions This study confirmed that TwinrabTM is noninferior to HRIG in terms of providing an unbroken window of protection up to day 84. This trial in healthy adults with WHO category III exposure from suspected rabid animal also establishes the safety of TwinrabTM in patients with 1 WHO approved vaccine regimen (Essen). Clinical Trials Registration CTRI/2017/07/009038.

scholarly journals Antibody titers measured by commercial assays are correlated with neutralizing antibody titers calibrated by international standards

2021 ◽  
Author(s):  
Yu-An Kung ◽  
Chung-Guei Huang ◽  
Sheng-Yu Huang ◽  
Kuan-Ting Liu ◽  
Peng-Nien Huang ◽  
...  
Keyword(s):  
Neutralizing Antibodies ◽  
Vaccine Development ◽  
Geometric Mean ◽  
Neutralizing Antibody ◽  
Diagnostic Techniques ◽  
International Standards ◽  
World Health ◽  
Serum Samples ◽  
Antibody Titers ◽  
Health Organization

The World Health Organization (WHO) has highlighted the importance of an international standard (IS) for SARS-CoV-2 neutralizing antibody titer detection, with the aim of calibrating different diagnostic techniques. In this study, IS was applied to calibrate neutralizing antibody titers (IU/mL) and binding antibody titers (BAU/mL) in response to SARS-CoV-2 vaccines. Serum samples were collected from participants receiving the Moderna (n = 20) and Pfizer (n = 20) vaccines at three time points: pre-vaccination, after one dose, and after two doses. We obtained geometric mean titers of 1404.16 and 928.75 IU/mL for neutralizing antibodies after two doses of the Moderna and Pfizer vaccines, respectively. These values provide an important baseline for vaccine development and the implementation of non-inferiority trials. We also compared three commercially available kits from Roche, Abbott, and MeDiPro for the detection of COVID-19 antibodies based on binding affinity to S1 and/or RBD. Our results demonstrated that antibody titers measured by commercial assays are highly correlated with neutralizing antibody titers calibrated by IS.

scholarly journals A Randomized, Open-label Study of the Pharmacokinetics and Safety of Oral and Intravenous Administration of Omadacycline to Healthy Subjects

2016 ◽  
pp. AAC.01393-16 ◽  
Author(s):  
Haiying Sun ◽  
Lillian Ting ◽  
Surendra Machineni ◽  
Jens Praestgaard ◽  
Andreas Kuemmell ◽  
...  
Keyword(s):  
Healthy Subjects ◽  
Geometric Mean ◽  
Oral Solution ◽  
Tablet Formulation ◽  
Absolute Bioavailability ◽  
Open Label ◽  
Phase 3 ◽  
Total Exposure ◽  
Oral Formulations ◽  
Tablet Formulations

Omadacycline is a first in class aminomethylcycline antibiotic with microbiological activity against Gram-positive and Gram-negative aerobes and anaerobes, and atypical bacteria that is being developed for the treatment of acute bacterial skin and skin structure infections (ABSSSI) and community-acquired bacterial pneumonia (CABP). The bioavailability of a Phase 3 tablet formulation relative to intravenous (IV) administration (and of other oral formulations relative to the Phase 3 tablet) was investigated in an open-label, randomized, four-period, crossover study in healthy subjects age 18-50 years. Subjects received omadacycline 100 mg IV, 300 mg oral as two different tablet formulations with different dissolution profiles, and a 300 mg as an oral solution. Plasma omadacycline concentrations were determined using a validated LC/MS/MS method. Twenty of 24 subjects completed all treatment periods. Both tablet formulations produced equivalent total exposure relative to each other. The Phase 3 tablet produced equivalent exposure to the 100 mg IV dose with geometric mean ratio (90% confidence intervals [CI]) for AUCinfof 1.00 (0.93,1.07). Absolute bioavailability of the tablets was approximately 34.5%. Intersubject variability was consistent among the oral formulations (∼20-25%). Single oral and IV doses of omadacycline were well tolerated; three subjects experienced mild adverse events (dizziness, nausea, vomiting) that resolved without intervention. A 300 mg dose of the tablet formulation of omadacycline intended for use in phase 3 studies produced total exposure equivalent to that of a 100 mg IV dose.

scholarly journals Neutralization of SARS-CoV-2 Omicron variant by sera from BNT162b2 or Coronavac vaccine recipients

2021 ◽  
Author(s):  
Lu Lu ◽  
Bobo Mok ◽  
Linlei Chen ◽  
Jacky Chan ◽  
Owen Tsang ◽  
...  
Keyword(s):  
Neutralizing Antibodies ◽  
Geometric Mean ◽  
Neutralizing Antibody ◽  
World Health ◽  
Whole Genome Sequence ◽  
Live Virus ◽  
Significant Difference ◽  
Antibody Titers ◽  
Ancestral Virus ◽  
Health Organization

Background The SARS-CoV-2 Omicron variant, designated as a Variant of Concern(VOC) by the World Health Organization, carries numerous spike protein mutations which have been found to evade neutralizing antibodies elicited by COVID-19 vaccines. The susceptibility of Omicron variant by vaccine-induced neutralizing antibodies are urgently needed for risk assessment. Methods Omicron variant strains HKU691 and HKU344-R346K were isolated from patients using TMPRSS2-overexpressing VeroE6 cells. Whole genome sequence was determined using nanopore sequencing. Neutralization susceptibility of ancestral lineage A virus and the Omicron, Delta and Beta variants to sera from 25 BNT162b2 and 25 Coronavac vaccine recipients was determined using a live virus microneutralization assay. Results The Omicron variant strain HKU344-R346K has an additional spike R346K mutation, which is present in 8.5% of strains in GISAID database. Only 20% and 24% of BNT162b2 recipients had detectable neutralizing antibody against the Omicron variant HKU691 and HKU344-R346K, respectively, while none of the Coronavac recipients had detectable neutralizing antibody titer against either Omicron isolates. For BNT162b2 recipients, the geometric mean neutralization antibody titers(GMT) of the Omicron variant isolates(5.43 and 6.42) were 35.7-39.9-fold lower than that of the ancestral virus(229.4), and the GMT of both omicron isolates were significantly lower than those of the beta and delta variants. There was no significant difference in the GMT between HKU691 and HKU344-R346K. Conclusions Omicron variant escapes neutralizing antibodies elicited by BNT162b2 or CoronaVac. The additional R346K mutation did not affect the neutralization susceptibility. Our data suggest that the Omicron variant may be associated with lower COVID-19 vaccine effectiveness.

scholarly journals Calibration of two validated SARS-CoV-2 pseudovirus neutralization assays for COVID-19 vaccine evaluation

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yunda Huang ◽  
Oleg Borisov ◽  
Jia Jin Kee ◽  
Lindsay N. Carpp ◽  
Terri Wrin ◽  
...  
Keyword(s):  
Neutralizing Antibodies ◽  
World Health ◽  
United States Government ◽  
Phase 3 ◽  
Efficacy Trials ◽  
Combining Data ◽  
The World ◽  
States Government ◽  
Common Scale ◽  
Aid Decision

AbstractVaccine-induced neutralizing antibodies (nAbs) are key biomarkers considered to be associated with vaccine efficacy. In United States government-sponsored phase 3 efficacy trials of COVID-19 vaccines, nAbs are measured by two different validated pseudovirus-based SARS-CoV-2 neutralization assays, with each trial using one of the two assays. Here we describe and compare the nAb titers obtained in the two assays. We observe that one assay consistently yielded higher nAb titers than the other when both assays were performed on the World Health Organization’s anti-SARS-CoV-2 immunoglobulin International Standard, COVID-19 convalescent sera, and mRNA-1273 vaccinee sera. To overcome the challenge this difference in readout poses in comparing/combining data from the two assays, we evaluate three calibration approaches and show that readouts from the two assays can be calibrated to a common scale. These results may aid decision-making based on data from these assays for the evaluation and licensure of new or adapted COVID-19 vaccines.

scholarly journals Calibration of Two Validated SARS-CoV-2 Pseudovirus Neutralization Assays for COVID-19 Vaccine Evaluation

2021 ◽  
Author(s):  
Yunda Huang ◽  
Oleg Borisov ◽  
Jia Jin Kee ◽  
Lindsay Carpp ◽  
Terri Wrin ◽  
...  
Keyword(s):  
Neutralizing Antibodies ◽  
World Health ◽  
United States Government ◽  
Phase 3 ◽  
Efficacy Trials ◽  
Combining Data ◽  
The World ◽  
States Government ◽  
Common Scale ◽  
Aid Decision

Abstract Vaccine-induced neutralizing antibodies (nAbs) are key biomarkers considered to be associated with vaccine efficacy. In United States Government-sponsored phase 3 efficacy trials of COVID-19 vaccines, nAbs are measured by two different validated pseudovirus-based SARS-CoV-2 neutralization assays, with each trial using one of the two assays. Here we describe and compare the nAb titers obtained in the two assays. We observe that one assay consistently yielded higher nAb titers than the other when both assays were performed on the World Health Organization’s anti-SARS-CoV-2 immunoglobulin International Standard, COVID-19 convalescent sera, and mRNA-1273 vaccinee sera. To overcome the challenge this difference in readout poses in comparing/combining data from the two assays, we evaluate three calibration approaches and show that readouts from the two assays can be calibrated to a common scale. These results may aid decision-making based on data from these assays for the evaluation and licensure of new or adapted COVID-19 vaccines.

scholarly journals Glycoprotein-Specific Antibodies Produced by DNA Vaccination Protect Guinea Pigs from Lethal Argentine and Venezuelan Hemorrhagic Fever

2016 ◽  
Vol 90 (7) ◽  
pp. 3515-3529 ◽  
Author(s):  
Joseph W. Golden ◽  
Piet Maes ◽  
Steven A. Kwilas ◽  
John Ballantyne ◽  
Jay W. Hooper
Keyword(s):  
South America ◽  
Dna Vaccine ◽  
Treatment Option ◽  
Guinea Pigs ◽  
Neutralizing Antibodies ◽  
Geometric Mean ◽  
Neutralizing Antibody ◽  
Dna Vaccination ◽  
Convalescent Phase ◽  
Antibody Cocktail

ABSTRACTSeveral members of theArenaviridaecan cause acute febrile diseases in humans, often resulting in lethality. The use of convalescent-phase human plasma is an effective treatment in humans infected with arenaviruses, particularly species found in South America. Despite this, little work has focused on developing potent and defined immunotherapeutics against arenaviruses. In the present study, we produced arenavirus neutralizing antibodies by DNA vaccination of rabbits with plasmids encoding the full-length glycoprotein precursors of Junín virus (JUNV), Machupo virus (MACV), and Guanarito virus (GTOV). Geometric mean neutralizing antibody titers, as measured by the 50% plaque reduction neutralization test (PRNT50), exceeded 5,000 against homologous viruses. Antisera against each targeted virus exhibited limited cross-species binding and, to a lesser extent, cross-neutralization. Anti-JUNV glycoprotein rabbit antiserum protected Hartley guinea pigs from lethal intraperitoneal infection with JUNV strain Romero when the antiserum was administered 2 days after challenge and provided some protection (∼30%) when administered 4 days after challenge. Treatment starting on day 6 did not protect animals. We further formulated an IgG antibody cocktail by combining anti-JUNV, -MACV, and -GTOV antibodies produced in DNA-vaccinated rabbits. This cocktail protected 100% of guinea pigs against JUNV and GTOV lethal disease. We then expanded on this cocktail approach by simultaneously vaccinating rabbits with a combination of plasmids encoding glycoproteins from JUNV, MACV, GTOV, and Sabia virus (SABV). Sera collected from rabbits vaccinated with the combination vaccine neutralized all four targets. These findings support the concept of using a DNA vaccine approach to generate a potent pan-arenavirus immunotherapeutic.IMPORTANCEArenaviruses are an important family of emerging viruses. In infected humans, convalescent-phase plasma containing neutralizing antibodies can mitigate the severity of disease caused by arenaviruses, particularly species found in South America. Because of variations in potency of the human-derived product, limited availability, and safety concerns, this treatment option has essentially been abandoned. Accordingly, despite this approach being an effective postinfection treatment option, research on novel approaches to produce potent polyclonal antibody-based therapies have been deficient. Here we show that DNA-based vaccine technology can be used to make potently neutralizing antibodies in rabbits that exclusively target the glycoproteins of several human-pathogenic arenaviruses found in South America, including JUNV, MACV, GTOV, and SABV. These antibodies protected guinea pigs from lethal disease when given post-virus challenge. We also generated a purified antibody cocktail with antibodies targeting three arenaviruses and demonstrated protective efficacy against all three targets. Our findings demonstrate that use of the DNA vaccine technology could be used to produce candidate antiarenavirus neutralizing antibody-based products.

scholarly journals Calibration of Two Validated SARS-CoV-2 Pseudovirus Neutralization Assays for COVID-19 Vaccine Evaluation

2021 ◽  
Author(s):  
Yunda Huang ◽  
Oleg Borisov ◽  
Jia Jin Kee ◽  
Lindsay N. Carpp ◽  
Terri Wrin ◽  
...  
Keyword(s):  
Neutralizing Antibodies ◽  
World Health ◽  
United States Government ◽  
Phase 3 ◽  
Efficacy Trials ◽  
Combining Data ◽  
The World ◽  
States Government ◽  
Common Scale ◽  
Aid Decision

Vaccine-induced neutralizing antibodies (nAbs) are key biomarkers considered to be associated with vaccine efficacy. In United States Government-sponsored phase 3 efficacy trials of COVID-19 vaccines, nAbs are measured by two different validated pseudovirus-based SARS-CoV-2 neutralization assays, with each trial using one of the two assays. Here we describe and compare the nAb titers obtained in the two assays. We observe that one assay consistently yielded higher nAb titers than the other when both assays were performed on the World Health Organization's anti-SARS-CoV-2 immunoglobulin International Standard, COVID-19 convalescent sera, and mRNA-1273 vaccinee sera. To overcome the challenge this difference in readout poses in comparing/combining data from the two assays, we evaluate three calibration approaches and show that readouts from the two assays can be calibrated to a common scale. These results may aid decision-making based on data from these assays for the evaluation and licensure of new or adapted COVID-19 vaccines.

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