AABB2025: Cryopreserved Platelets Noninferior to RT Platelets in Cardiopulmonary Bypass

CLPH-511, Cellphire Therapeutics’ investigational cryopreserved platelet product, appears to be noninferior to standard room-temperature platelets in controlling blood loss during cardiopulmonary bypass surgery, according to findings from a new study presented at the 2025 AABB Annual Meeting. Glenn Whitman, MD, of Johns Hopkins Medical Institute, presented the study’s topline data during the Sunday afternoon session, “Update on the Use of Cryopreserved Platelets in Acute Surgical Settings.”

The phase 2/3 CRYPTICS (Cryopreserved Platelet Trial for Control of Bleeding in Surgery) study was a randomized, parallel-group trial that enrolled 312 adult patients undergoing complex cardiac surgery, including first and repeat median sternotomies. Participants were randomized on the day of surgery to receive either CLPH-511 (n=151) or room-temperature platelets (n=161). The primary endpoint, total chest tube drainage at 24 hours, averaged 1,150 cc in the CLPH-511 group and 1,011 cc in the room-temperature platelet group, a difference that was not statistically significant. Adverse events, including mortality, thromboembolic complications and serious postoperative events, were similar between the two groups.

CLPH-511 units were produced from pooled donor platelets and stored frozen at cardiac surgery facilities. On the day of surgery, the products were thawed and reconstituted with saline, a process that took about 20 minutes before transfusion.

Cellphire Therapeutics, an AABB corporate partner, plans to meet with the Food and Drug Administration to discuss next steps in the clinical development of CLPH-511.