Figure 1.
HTS Screening and hit identification. A, HTS campaign of 56,557 compounds conducted against recRSV-A2-L19FD489E-fireSMASh. For each compound, robust z-scores and percentage inhibition values were calculated, and hit cutoff for each analysis method is shown (dashed lines). The inset summarizes counterscreening results obtained for 139 primary screen hit candidates that met both inclusion criteria. B, automated dose–response potency and cytotoxicity testing in 384-well format for 13 hit candidates advanced from A. Compounds with CC50 <20 μm, SI <1, or EC50 ≥5 μm were discontinued. Primary HTS and automated counterscreens in A and B were carried out in single biological repeats. C, structure of GRP-156784, the primary hit candidate passing all performance milestones. Numbers and dashed red circles denote scaffold sections modified individually for synthetic hit-to-lead development.