Novelty, synthesizability, and safety are not independent goals. They compete, and a candidate is only useful if it clears all three at once.
What each pressure rewards and punishes
Novelty
- Rewards: structures unlike known compounds, escaping existing patents and known liabilities
- Punishes: unfamiliar scaffolds are harder to make and less covered by prior safety data
Synthesizability
- Rewards: chemistry close to known reactions, short routes, good yields
- Punishes: pushing toward familiar structures, which reduces novelty
Safety
- Rewards: features that avoid off-target binding and instability
- Punishes: tight, unusual binding features that may also hit unintended proteins
A model that optimizes predicted binding alone will propose molecules that cannot be made or should not be given to anyone. The design goal is a molecule acceptable on all three axes, not maximal on one.