SAE is a serious adverse event, and may or may not be related to the drug…the latter determination is usually reserved to the principal investigator at the trial site, most often a physician who looks at the totality of what transpired and renders a professional opinion. GI upset in my book would not be a serious adverse event. ITP and the fatal clots which have occurred (albeit rarely) with MRNA vaccines and in particular cerebral or portal vein clots which carry a 25% fatality would be properly viewed as “serious.” This is as opposed to side effects, often pretty well characterized…if you get constipated taking opioids that is a side effect and understood to be that and not an SAE. There is another nuance I will throw out there and that is intolerance…some drugs may be well tolerated but in certain individuals the side effects spill over to the level of intolerance such that they really should avoid the drug entirely. Correct me if I’m wrong but I am not aware of any SAE with Leronlimab that was attributed to the drug and not merely associated with the patient by virtue of other treatments; examples would be taking cisplatin for cancer or underlying pathology such as cancer itself. If I have cancer and report “ fatigue” it is more likely the disease talking, not a drug such as Leronlimab.