Table 1.
Immune correlates analysis of TV003-induced antibodies and sterilizing immunity upon DENV2 challenge.
| Predictor | Odds of experiencing a ≥2-fold boost in DENV2 nAb titer after challenge given predictor nAb levels above indicated threshold | Correlation of pre-challenge nAb titer with boost in DENV2 nAb titer after challenge (Pearson’s product-moment correlation) | ||||
|---|---|---|---|---|---|---|
| Threshold titer of nAb | Odds % ratio | 95% CI | p-value | Correlation | p-value | |
| Geometric mean of nAbs to all four DENV serotypes | 138 | 0.4 | 0.05–3.12 | 0.382 | 0.15 | 0.515 |
| Total titer DENV2 nAb | 74 | 0.35 | 0.04–3.08 | 0.341 | −0.23 | 0.313 |
| Type-specific titer DENV2 nAb | 20 | 0.1 | 0.01–0.97* | 0.047 | −0.39 | 0.079 |
| % of DENV2 Type-specific nAb | 0 | 0.1 | 0.01–0.97* | 0.047 | −0.44 | 0.046* |
All 21 vaccinated subjects (n = 21) were challenged with a partially attenuated strain of DENV2 6 months after vaccination. Sterilizing immunity is defined as <2-fold increase (compared to pre-challenge levels) in DENV2 nAb at day 28 after challenge.
Asterisk indicates significant correlations are in bold.
% The odds of experiencing a ≥2-fold boost in DENV2 nAb titer post-challenge was estimated by predictor nAb level, thresholded by decile. The threshold for the decile with the most significant relationship with fold-boost is presented. The threshold corresponding to the 20th percentile had the lowest p-value for the predictors: Total DENV2 nAb, TS DENV2 nAb, and % of TS DENV2 nAb. The threshold corresponding to the 40th percentile was most significant for the predictor Geometric mean of nAb titers to all four DENV serotypes. Predictors, geometric mean of nAb titers to all four DENV serotypes and total DENV2 nAb were not associated with a significant protective effect for any threshold value tested (20th, 30th, 40th, 50th, 60th, 70th, 80th percentiles).
Data were analyzed by an exploratory statistical analysis to evaluate the relationship between pre-challenge nAb titer and boost in DENV2 nAb titer post-challenge. The correlation between predictor and outcome variables were evaluated by using pearson’s product-moment correlation. The odds ratio analysis of ≥2-fold boost in DENV2 nAb titer for those with predictor nAb levels above vs. at or below a specified threshold were estimated us the mosaic package in R.