CytoSorbents, a critical care immunotherapy company working to control inflammation and save lives in the ICU through blood purification with its European Union approved CytoSorb cytokine filter, provides an end-of-year update on its CytoSorb Dosing study that is currently ongoing.
The CytoSorb Dosing study ("Dosing study") is a multi-center trial being conducted amongst 8 leading clinical sites in Germany and is an extension of CytoSorbents’ previous randomized controlled European Sepsis Trial (EST).
The EST demonstrated CytoSorb was a safe and effective broad spectrum cytokine filter, reducing cytokine storm and key cytokines by 30-50% in patients with septic shock and respiratory failure when used 6 hours a day for 7 days (See summary of the European Sepsis Trial).
A post-hoc analysis of the EST clinical data also suggested that patients with either high cytokine levels or 65 years of age or older, benefitted the most from the therapy, including improvements in 28-day and 14-day survival, respectively.
The Dosing study was designed to evaluate the safety and preliminary efficacy of extended CytoSorb treatment in septic patients with respiratory failure using the same inclusion and exclusion criteria as the EST. The major goals of the study were to:
• Obtain safety data on extended CytoSorb treatment
• Confirm CytoSorb cytokine removal over an extended period of usage
• Provide clinicians with more flexibility on how to treat critically ill patients with CytoSorb
• Obtain data to help optimize treatment and support the design of a US pivotal sepsis trial to prove effectiveness. This Dosing study was not intended to produce statistically significant data on clinical endpoints.
There are two CytoSorb® treatment protocols being evaluated in the Dosing study: 1) 24 hours per day for 7 days and 2) 6 hours per day for up to 14 days, each day using a new device. Currently, only the 24-hour treatment arm is enrolling patients.
The intent is to compare these two arms against clinical outcomes from control and treated patients in the EST (6 hours a day for 7 days) using a matched pairs analysis strategy.
In this analysis, all patients in the Dosing study are treated with CytoSorb®, and then are later matched and compared to patients from the EST trial using variables in common such as age = 65 years old, need for dialysis, APACHE 2 score, cytokines, and other factors.
There have been 28 patients enrolled into the first arm (24 hours of treatment for 7 days) of the trial to date. Preliminary analysis of the available data suggest the following:
• CytoSorb® treatment is well tolerated at flow rates up to 300 mL/min, with no serious device related adverse events in the trial to date. 24-hour treatment increases platelet reduction compared to 6-hour treatment in the EST, but with no reported complications.
• CytoSorb® is compatible with a variety of antibiotics including aminoglycosides and broad-spectrum antibiotics, such as the carbepenem class, which require only modest dose adjustments. Additional antibiotic testing is underway.
• CytoSorb® is concentration dependent and continues to actively remove IL-6 during the entire 24-hour treatment period, higher at the beginning of treatment when IL-6 levels are highest, and with an overall average instantaneous IL-6 reduction of 8% per pass. For each patient, approximately 60-70 total blood volumes, the equivalent of approximately 300 liters or 75 gallons of blood, are treated per day. In an in vitro blood perfusion system with no cytokine production, this equates to a rapid and greater than 99% reduction of IL-6. In the body, however, with active ongoing cytokine production, the overall reduction is less.
• Safety data obtained from this study on continuous 24-hour treatment will be used to provide additional examples in the "Instructions for Use" document that accompanies the product for commercial usage. This will provide additional flexibility in how physicians use CytoSorb® in sepsis and other critical care applications.
• The first treatment arm continues to enroll patients. In this preliminary analysis, the overall 28-day all-cause mortality and 28-day all-cause mortality in patients 65 years and older is statistically similar to the treatment data reported in the EST (electronic randomized cohort). Severity of illness in the overall treatment groups were comparably high, with 50% or more of the treated patients (dosing > EST) having an APACHE 2 severity of illness score > 25 at the time of enrollment, predicting very high mortality of 55% or more. In comparison, the overall control patients reported in the EST (electronic randomization cohort) had a lower severity of illness with only 20% having an APACHE 2 score > 25.
• Cytokine analysis and matched pairs analysis is currently ongoing, and 60-day mortality data is still pending on many recently enrolled patients.
Dr. Phillip Chan, MD, PhD, CEO of CytoSorbents, stated, "We are pleased that 24-hour treatment with CytoSorb® has been safe and easy to implement to date, and that it demonstrates robust continuous cytokine removal across the entire treatment period as expected. We are also encouraged that the first arm of the Dosing study has already treated more patients than in the reported data from the EST, and that we are seeing similar trends in a very heterogenous, critically ill patient population. This first arm of the trial has generated many interesting insights that will help to modify the second arm of the trial."
Dr. Chan continued, "Our understanding of how to use CytoSorb® to treat severe sepsis and septic shock, and other critical illnesses continues to advance. This dosing study, nearly 30 post-market investigator initiated studies either starting or being planned, multiple case report studies, and the establishment of an international treatment registry, are part of a much larger plan to generate a significant amount of clinical data in coming months to years that will help physicians optimally treat their patients with CytoSorb®."