Reading through the document:
"Whether a surrogate endpoint is reasonably likely to predict clinical benefit is a function of the scientific plausibility of the relationship between the disease, endpoint, and the expected device
effect, and the empirical evidence to support that relationship. The empirical evidence may include epidemiological, pathophysiological, therapeutic, or other scientific evidence. When considering evidence of a predictive relationship between the endpoint and clinical benefit, it is important to do so in the context of the nature of the disease as well as the mechanism of action of the device.
Use of a surrogate endpoint depends on the quality of data and strength of evidence supporting the measure, and on the context in which it is applied (“context of use”).32 When there is strong evidence demonstrating a predictive relationship between a measure and clinical benefit, it may be accepted for use as a “well-established” surrogate endpoint in a clinical study which will serve as the basis for approval. A measure which is reasonably likely to predict clinical benefit
could be used as a basis for regulatory approval in some instances such as for an EAP Device"
I don't think there's been any trials that have shown IL-6 reduction does indeed lead to better survival outcome. When I searched, I did not see any trials done in sepsis with the IL-6 antibodies, though they are being used in same cases with CAR-T therapy. Thus, I have a harder time believing that reduction of IL-6 will be accepted as a surrogate endpoint. Though there is clinical evidence pointing that high IL-6 leads to more mortality, reducing that does not guarantee increased survival.
