Pre-treatment lymphocyte count predicts Thymosin alpha 1 efficacy in acute necrotising pancreatitis

Patients with acute necrotising pancreatitis (ANP) often suffer from infected pancreatic necrosis (IPN), a severe complication associated with high morbidity and mortality. Current standard-of-care treatments for ANP are often insufficient to prevent IPN, highlighting a critical need for immune-modulating therapies. Thymosin alpha 1 (Tα1) is an immune-enhancing peptide known to modulate T-cell function and other immune responses. Its efficacy in ANP may be influenced by the patient's baseline immune status, specifically their absolute lymphocyte count (ALC), which Tα1's pharmacological action directly impacts.

This was a post-hoc analysis of the multicentre, double-blind, randomised, placebo-controlled TRACE trial, involving 502 patients with predicted severe ANP from 16 hospitals in China. Patients were randomised to receive Tα1 1.6 mg subcutaneously (SC) every 12 hours for the first 7 days, followed by 1.6 mg once daily for the subsequent 7 days, or a matching placebo. Three subgroup analyses were conducted based on baseline ALC at randomisation. The primary outcome was the incidence of IPN 90 days after randomisation. A fitted logistic regression model was used to identify the optimal range of baseline ALC for Tα1 efficacy.

Out of 508 patients initially randomised in the TRACE trial, 502 were included in this post-hoc analysis (248 in the Tα1 group, 254 in the placebo group). The analysis aimed to determine if pre-treatment ALC influenced the efficacy of Tα1 therapy in reducing IPN. Across the three predefined subgroups based on baseline ALC, researchers observed a uniform trend indicating more significant treatment benefit from Tα1. The study applied a logistic regression model to pinpoint the specific range of baseline ALC where Tα1 therapy could exert its maximum effect. However, the abstract does not provide the specific numerical range of ALC identified or the quantified reduction in IPN within that optimal range. It concludes that such a range was identified where: Tα1 therapy could exert a maximum effect, suggesting ALC as a potential biomarker for patient selection.