Figure 1 -Illustration of our proposed approach. After carrying out a HTS campaign, the most active compounds in the primary screen are usually prioritized for further testing. However, this strategy often does not distinguish well between true positives (TP) and false positives (FP), leading to high false positive rates in confirmatory screens. In our approach, we first fit a GBM classifier on the primary HTS screen data, and compute MVS-A scores for each active compound.