Poolbeg Pharma (POLB)  has published a peer-reviewed paper from its POLB 001 bacterial lipopolysaccharide (LPS) human challenge trial in Frontiers in Immunology, highlighting reductions in key inflammatory biomarkers and a favourable safety profile.

The randomised, double-blind, placebo-controlled study assessed POLB 001’s ability to suppress local and systemic inflammatory responses in healthy volunteers. The paper confirms POLB 001’s mechanism as a potent inhibitor of p38 mitogen-activated protein kinase (p38 MAPK) driven cytokine responses.

Poolbeg said POLB 001 reduced immune cell recruitment following LPS challenge, with the strongest suppression in neutrophils by 72.4% to 81.5%, classical monocytes by 68.4% to 73.6%, CD3+ T cells by 56.4% to 65.9%, and myeloid dendritic cells by 59.0% to 64.4%. Meanwhile, cytokine suppression was most pronounced for tumour necrosis factor (TNF), reduced by 35.3% to 65.1%.

The company added that POLB 001 did not substantially modulate the intradermal LPS-driven increase in local erythema and perfusion. However, it reduced the intravenous LPS-driven increase in interleukin 6 (IL-6), interleukin 8 (IL-8), and TNF by 37.7% to 80.7%, alongside reductions in p38 MAPK phosphorylation levels in target cells by 16.7% to 60.9% and heart rate increase by 4.0 to 9.3 beats per minute.

Poolbeg’s CEO Jeremy Skillington said: “The publication of peer-reviewed clinical data from our LPS challenge trial in Frontiers in Immunology is an important milestone for Poolbeg. The positive data from this trial highlights that oral treatment of POLB 001 holds great promise in addressing cancer immunotherapy-induced CRS and supports further clinical development of the asset, including the POLB 001 TOPICAL clinical trial.”

Poolbeg said interim data from the POLB 001 TOPICAL trial is anticipated this summer.

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A peer-reviewed publication is a helpful validation step, particularly for an asset targeting a well-known inflammatory pathway. While an LPS challenge model is not the same as cancer immunotherapy, the scale of cytokine and immune cell effects, alongside tolerability, supports the biological rationale ahead of the TOPICAL interim readout.