Comparing cryoprecipitate-poor plasma to fresh frozen plasma as replacement therapy in thrombotic thrombocytopenic purpura: An updated meta-analysis.

Background: Cryoprecipitate-poor plasma (CPP) has been suggested as a promising alternative to the standard fresh frozen plasma (FFP) in plasma exchange therapy (TPE) for thrombotic thrombocytopenic purpura (TTP) given its lower concentrations of von Willebrand Factor (VWF). However, its efficacy and safety remain a topic of debate.

Study design and methods: We conducted a systematic review and meta-analysis comparing CPP to FFP during TPE in patients with TTP. PubMed, Embase, and Cochrane Central were systematically searched for studies reporting outcomes of all-cause mortality, relapse rate, response to treatment, and the mean number of TPE sessions. Sensitivity analyses restricted to randomized controlled trials (RCTs) were performed. Review Manager v5.4 and RStudio v4.1.2 were used for statistical analysis. The protocol was prospectively registered in PROSPERO (ID CRD42023440665).

Results: Eight studies, including three RCTs and five non-randomized studies, met the eligibility criteria. A total of 290 patients with TTP were included, of whom 144 (49.7 %) received CPP and 146 (50.3 %) received FFP. Use of CPP was associated with lower mortality (RR 0.41; 95 % CI 0.23-0.72; p = 0.002; I²=0 %), while the subgroup analysis restricted to RCTs showed no statistical difference between groups (p = 0.36). No significant differences were found in relapse rate, response to treatment, or mean number of TPE sessions between groups.

Conclusion: Our findings show that the use of CPP is not inferior to FFP in TPE. Given the limited population, future clinical trials are needed to elucidate its benefits compared to FFP in patients with TTP.