How much biomarker data are you collecting in your Phase I?

Many small biotech teams treat Phase I like a safety study with some biomarker data on the side.

Completely backwards.

Phase I should be your most intensive biomarker collection period.

Here's what everyone gets wrong:

They think Phase II is when biomarker strategy matters.
By then, you've already missed your best opportunities.

Phase I dose escalation gives you something you'll never get again:
multiple dose levels in the same study.

This is biomarker gold.

You can see dose-response relationships for pharmacodynamic markers.
Understand mechanism of action across different exposures.
Identify the dose that actually hits your target.

Most teams collect minimal biomarker data in Phase I, then scramble to understand their drug in Phase II.

Bad strategy.

Phase II patients all get the same dose.
You lose the dose-response insights forever.

Predictive biomarkers?
Even more important to start early.

Yes, Phase I patient numbers are small.
But you can validate your collection procedures.
Train your sites.
Work out the operational kinks.

And if you design it right, you might catch predictive patterns that completely change your Phase II approach.

Use Phase II to confirm what you learned, not to start learning.

How much biomarker data are you collecting in your Phase I?