B52,
Two studies are cited in this paper for Cytosorb treatment. A cardiac and a Sepsis study. If you take the time to review the actual data of these studies you will see that the cytokine levels in each of the studies were relatively low to start with. For example I believe the Cardiac trial had IL-6 levels in 100 pg/ml range and in the sepsis trial they topped out at just over 500. Keep in mind that Cytosorb is concentration dependent. The higher the cytokine levels the greater the rate of adsorption. In both these trials the cytokine levels were relatively low compared to many of the other case studies, where positive results were seen, where the levels were in the thousands to tens of thousands pg/ml. These two studies were more like safety studies than efficacy and effectiveness studies as the cytokine levels were just not high enough to even expect a large negative impact from them.
As an analogy, let’s say we want to do a study on the effectiveness of motorcycle helmets preventing brain injury. We have two arms of the study. One with riders who wear helmets and one with riders who do not. If at the end of the study there are no accidents reported and both arms reported no brain injuries, would it be correct to conclude that wearing a motorcycle helmet offers no more protection from brain injury than not wearing one?
Also note that the REFRESH 2 trial, the US phase 3 cardiac trial, is not focused on cytokine reduction but instead on the removal of plasma free hemoglobin, with a hope to reduce the incidents of AKI.
