Publications by authors named "J C Ryman"
Article Synopsis
- A Value of Information (VOI) analysis helps in making decisions about new approach methodologies (NAMs), specifically applied to the Threshold of Toxicological Concern (TTC).
- The study shows that using TTC as a toxicity reference value is more cost-effective, providing better health protection, greater return on investment (ROI), and lower costs of delay compared to traditional toxicity testing methods.
- TTC yields an average ROI of 5,000,000-fold, significantly outperforming traditional methods (THHA) and the ETAP, suggesting it can be used to bypass certain in vivo tests or serve as a preliminary screening tool.
Article Synopsis
- Next generation pneumococcal conjugate vaccines (PCVs), specifically V114 and PCV20, are evaluated by comparing their immune responses to those of the standard PCV13 used to prevent pneumococcal disease.
- The study predicts vaccine effectiveness (VE) against invasive pneumococcal disease in children from the EU, Russia, and Australia, showing that V114 generally has higher VE compared to PCV20.
- Results indicate that V114 exhibits greater protection against specific serotypes, especially serotype 3, while PCV20's effectiveness is lower than that of PCV13 for several serotypes, highlighting the need for real-world studies to confirm these predictions.
Background: Next-generation, higher-valency pneumococcal conjugate vaccines (PCVs), 15-valent PCV V114 and 20-valent PCV (PCV20), have been assessed by comparing their immune responses across serotypes shared with the 13-valent PCV (PCV13). Without efficacy or real-world vaccine effectiveness (VE) it becomes important to relate IgG titers to VE to aid in the interpretation of the immune response elicited by V114 and PCV20.
Methods: We estimated the protective antibody concentrations for each serotype in 7-valent PCV (PCV7) and PCV13 which were then used to predict the serotype-specific VE for each PCV7 and PCV13 non PCV7 serotype present in V114 and PCV20.
The strength of the immune response, as measured by antibody concentrations, varies between pneumococcal conjugate vaccines (PCVs). Linking immunogenicity and effectiveness is necessary to assess whether changes in immune response from currently recommended PCVs to next-generation vaccines could impact effectiveness. Simulated reverse cumulative distribution curves were generated using published serotype-specific IgG concentrations with placebo or PCV7.
View Article and Find Full Text PDFBackground: The potential impact of new pneumococcal conjugate vaccines (PCVs) is assessed by using immune responses to predict their effectiveness against invasive pneumococcal disease (IPD). This analysis predicted the serotype-specific effectiveness against IPD of a new 15-valent PCV (V114) for the serotypes shared with a 13-valent PCV (PCV13), in a US pediatric population given a 3 + 1 dosing regimen.
Methods: Beginning with the known serotype-specific antibody concentrations after vaccination with placebo, 7-valent PCV (PCV7) and PCV13, reverse cumulative distribution curves were used, along with published serotype-specific vaccine effectiveness of PCV7 and PCV13, to derive a protective antibody concentration (C) for each PCV13 serotype in V114.