Rationale for trial protocol amendment "The current intent for the protocol amendment is to modify the dosage regimen to optimize the delivery of TH1902, with lower doses at more frequent intervals. The Company continues to investigate the results obtained thus far in the Phase 1 clinical trial."
If they saw no sign of efficay, why would they try to "optimize the delivery"?
"Efficacy results observed thus far were not convincing enough to pursue enrolling patients and did not outweigh the adverse events seen in some patients"
This implies they saw both some sign of efficacy AND adverse events. So, there is a need to strike a balance by just using the right dosage (optimized) to preserve efficacy while avoiding/reducing adverse events.
They believes that lower dosage with more frequent delivery of TH902 would achieve that balance.
How low? Well, that's what they need to investigate by reviewing existing Phase 1a/b data.