Dr. Clark is the Medical Director of Transfusion Medicine at the University of Tennessee Medical Center.
This is the first installment in what will be a regular series of questions and answers with blood industry thought leaders. This installment looks at Acrodose, an FDA-approved whole blood derived alternative to apheresis Single Donor Platelets. Bloodbuy is not affiliated with Haemonetics, the provider of the Acrodose system, although Acrodose products are available on the Bloodbuy platform.
Q: Why do you think pooled platelets, and Acrodose in particular, have not reached wider acceptance?
Two major advantages of pooled platelets are increased platelet product availability and decrease in cost per product. However, there are additional advantages. In years past, single unit whole blood derived platelets were pooled in the blood bank. These individual units do not have sufficient volume for a routine culture to be performed. Bacterial contamination is a major concern with platelet products. An advantage of pre-pooled platelet products is sufficient volume, allowing the ability to perform a culture. Acrodose pre-pooled method also allows the product to be ABO matched and leukoreduced. Many of the advantages we once attributed to apheresis (single-donor) platelets can be now achieved in pooled platelets with leukoreduction.
Q: Would you consider Acrodose clinically equivalent to single donor platelets?
Studies have shown that in the area of hemostatic benefit, HLA alloimmunization risk, Anti-D alloimmunization risk, TRALI risk and risk of other adverse reactions, apheresis platelets and whole-blood-derived platelets are considered equivalent. Studies do report that apheresis platelets achieve higher post-transfusion platelet counts and CCI when used prophylactically; however, these studies also report that this does not appear to translate into lower risk of significant bleeding in this patient population.
Other authors report increased time interval between need for prophylactic platelet transfusion in cancer patients, particularly AML patients, with whole-blood-derived platelets. There is suggestion of slightly higher risk of bacterial contamination with whole-blood-derived platelets; however, many of these reports are before the time of current bacterial-risk mitigation strategies. With leukoreduction, routine primary bacterial testing and the upcoming proposed secondary bacterial testing of Day 3 and/or Day 4 platelets, I suspect the difference in bacterial risk will be further decreased.
Q: How valid are concerns regarding increased risk of viral contamination in Acrodose? How would you address those concerns?
The data regarding risk of viral transmission in apheresis vs. whole-blood platelets is inconclusive. It would seem logical that potential viral exposure to 4-6 donors in a pooled whole-blood platelet unit would be greater than that of an apheresis (single-donor) platelet unit. However, in the current state with rigorous donor screening and NAT testing, the risk of viral transmission is likely comparable, considering the adverse event of transfusion-associated viral transmission is very low in the United States.
Q: Are there circumstances where Acrodose or SDP are preferred?
At our institution, we are implementing use the Acrodose or SDP product nearest to outdate for any patient needing platelet transfusion. The only time SDP unit is universally used is for our NICU patients.
Q: What are the regulatory changes that you would like to see regarding Acrodose?
In current state, pooled platelet products, including Acrodose, are not eligible for use on Day 6 or 7 even with secondary bacterial testing. In addition, Acrodose is not currently approved for pathogen inactivation techniques. As time progresses and pathogen inactivation becomes more cost effective and widely utilized, being able to utilize pathogen-inactivated-whole-blood derived platelets up to Day 7 would greatly increase availability of platelet products, decrease product wastage, and likely significantly increase the safety profile.
Questions by Brian Witte, Ph.D., Research & Development at Bloodbuy