In the Phase 3 Tigris trial of 157 adults with endotoxic septic shock, polymyxin B hemoadsorption (PMX) achieved a 95.3% posterior probability of benefit on 28‑day mortality, with an adjusted odds ratio of 0.67 and an adjusted absolute risk reduction of 10.3% (number needed to treat 9.7). The key secondary endpoint was stronger: a 99.4% probability of benefit on 90‑day mortality, an adjusted odds ratio of 0.54, and an adjusted absolute risk reduction of 15.5% (NNT 6.5). Survival over 90 days favored PMX with a posterior hazard ratio of 0.68. Safety was aligned with standard care: overall adverse events were comparable; serious adverse events occurred in 30% of PMX patients versus 22% on standard care, a nonsignificant difference, with two intervention‑related SAEs that resolved without lasting effects.
The full results, now published in The Lancet Respiratory Medicine and slated for presentation at SCCM, detail a U.S. multicenter, randomized 2:1 evaluation of PMX plus standard care versus standard care alone in patients selected by an Endotoxin Activity Assay (EAA 0.60–0.90) and high organ dysfunction (MODS >9 or SOFA >11). The prespecified Bayesian primary analysis borrowed prior information from a defined EUPHRATES subgroup in line with FDA’s guidance for device trials. Spectral plans to submit the final PMA module for PMX to FDA in late April to mid‑May 2026. Vantive holds exclusive distribution rights for PMX in the U.S. and Canada and intends to commercialize both EAA and PMX if approved.
Strategically, this is a precision, theranostic play designed to rescue a once‑contested modality by tightly phenotyping the target population and leaning on Bayesian borrowing to reach a probability‑based threshold. The emphasis on 90‑day mortality — where the confidence interval excludes no effect and survival curves continue to separate beyond day 28 — reframes expectations in a field where many trials stall at shorter time points. The trade‑off is obvious: a modest sample size, dependence on a prior from earlier data, and a primary 28‑day adjusted interval that crosses unity, set against a rigorously defined cohort and a coherent biologic mechanism.
For ICU sites, the operational signal is concrete. Broad adoption would require 24/7 access to rapid EAA testing, streamlined workflows to initiate extracorporeal hemoadsorption in parallel with sepsis bundles, and coordination with dialysis teams for catheter placement and anticoagulation. If the mortality effect translates, NNTs in the 7–10 range could justify investment, but payers will press for evidence on ICU‑free days, ventilator‑free days, and length‑of‑stay impacts. For sponsors and CROs, Tigris underscores the growing acceptability of Bayesian device designs and diagnostic‑enriched enrollment in heterogeneous, time‑critical syndromes. Regulators face a familiar balance: rewarding targeted selection and consistent 90‑day outcomes while constraining labeling to the EAA‑defined window and severity thresholds that drove the signal.
Next, watch the PMA file for the weight placed on 90‑day mortality, the extent of reliance on prior data, and any advisory panel move. Label scope will determine real‑world reach; post‑market commitments and a prospective registry are likely given historical variability in sepsis trials. Commercial viability hinges on reimbursement mechanics, including DRG fit, potential NTAP pathways, and creation of clear billing routes for the assay‑device bundle. Operationally, success will depend on training, catheter and circuit logistics, and supply reliability across high‑acuity centers. Competitive dynamics with other blood purification approaches will intensify, and head‑to‑head data are absent. The core question for 2026–2027 is whether a tightly guided endotoxin‑removal strategy can win U.S. approval — and whether real‑world performance in diverse ICUs matches the curated signal seen in Tigris.
Jon Napitupulu is Director of Media Relations at The Clinical Trial Vanguard. Jon, a computer data scientist, focuses on the latest clinical trial industry news and trends.
