oXiris-Based Blood Purification Efficacy in Adults with Septic Shock and Acute Kidney Injury: The PURE Multicenter Pilot Randomized Clinical Trial

Background/Objectives: Randomized evidence for the oXiris adsorptive membrane in septic shock remains limited. We estimated its effect on 28-day mortality and explored short-term physiologic outcomes in adults with septic shock and acute kidney injury requiring continuous renal replacement therapy. Methods: PURE was a multicenter, single-blind, parallel-group pilot randomized trial in Saudi Arabia. Participants were randomized 1:1 to oXiris-based or conventional continuous venovenous hemodialysis. The primary comparison used unadjusted mortality risk estimates. Secondary observations were summarized descriptively; adjusted and post-hoc Bayesian sensitivity analyses are reported in the main text and supplement. Results: Of 204 randomized participants, 202 were analyzed (oXiris, 100; control, 102). Twenty-eight-day mortality was 39.0% (39/100) versus 47.1% (48/102), respectively (risk ratio, 0.83; 95% CI, 0.60–1.14; risk difference, −8.1 percentage points; 95% CI, −21.7 to 5.6; p = 0.247). Reported 72 h norepinephrine dose, lactate, C-reactive protein, and Sequential Organ Failure Assessment (SOFA) score were lower with oXiris; reported intensive care unit (ICU) stay was also shorter. Secondary descriptive observations are limited by unverifiable time-specific denominators and handling of intercurrent events. Premature filter clotting was reported in 8/100 versus 7/102 participants; no device-related adverse events were reported, but safety ascertainment was limited. Conclusions: This pilot trial did not demonstrate a statistically significant reduction in 28-day mortality, although mortality was numerically lower in the oXiris group. Consistent protocol implementation and encouraging, hypothesis-generating physiologic observations provide a foundation for a definitive trial with complete longitudinal ascertainment.