i think, going off Madrigal's thinking, one way we can know whether or not to continue with leronlimab treatment would be through the use of only one biomarker, T4.

Before any treatment at all, we should get baseline T4.
We should plan on treating in 14 week intervals.
Before the 1st treatment interval of 350mg LL weekly, get baseline T4.
Do 14 weeks of 350mg LL sub-q weekly
Repeat T4 after 14 weeks.
If higher than baseline, do another 14 weeks of LL treatment.
If equal to or less than baseline, stop LL treatment. It is ineffective.
If performing 2nd Interval of 14 weeks.
Once complete, measure T4 again and compare to baseline, (not to the previous T4 at end of 1st interval).
If higher than baseline, do another 14 weeks of LL treatment.
If equal to or less than baseline, stop LL treatment. It has become ineffective.

In general, LL will raise T4 while it is working. LL is only effective when a low dose is given while disease burden is high. Since it is only the liver being treated, there are fewer CCR5 receptors, but with an inflammed liver, there will be more, but 350mg seems to be the magic number.
As the patient's health improved, there will be fewer CCR5 receptors to attach to and so, leronlimab's effect will be reduced and subsequently T4 will go back down to baseline.