Anavex Life Sciences Corp (AVXL)

[Steady_T]

There is a distinction between the various classes of biomarkers.

Simple Methods for Evaluating 4 Types of Biomarkers: Surrogate Endpoint, Prognostic, Predictive, and Cancer Screening

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7412628/#:~:text=PMID%3A%2032821082-,Simple%20Methods%20for%20Evaluating%204%20Types%20of%20Biomarkers%3A%20Surrogate%20Endpoint,Prognostic%2C%20Predictive%2C%20and%20Cancer%20Screening

Surrogate biomarkers can be used in AA applications for suggestion of clinical efficacy.
Diagnostic biomarkers can not be used for AA as surrogates.

Certainly being able to show several biomarker changes as a result of drug administration indicates that the drug is having an effect.
The question is does that effect translate into clinical efficacy.
The FDA has a process for certifying a biomarker as a surrogate. In general the FDA doesn't want a trial to attempt to certify a biomarker as a surrogate and then use that surrogate in the same trial for AA.