Safety, clinical activity, pharmacodynamics, and pharmacokinetics of IMU-856, a SIRT6 modulator, in coeliac disease: a first-in-human, randomised, double-blind, placebo-controlled, phase 1 trial

Background

IMU-856 is an orally available and systemically acting small molecule modulator of sirtuin 6 (SIRT6), a protein that serves as a transcriptional regulator of bowel epithelium regeneration. We aimed to evaluate the safety, clinical activity, pharmacodynamics, and pharmacokinetics of IMU-856 in healthy participants and in patients with coeliac disease.

Methods

This study reports the results from a completed first-in-human, three-part, double-blind, randomised, placebo-controlled, clinical trial of IMU-856 in healthy participants and patients with coeliac disease done in Australia and New Zealand. In part A, healthy participants were enrolled in six cohorts and randomly assigned (3:1) using a block randomisation algorithm to receive single ascending doses of IMU-856 ranging from 10 mg to 160 mg or matching placebo. Based on the results from part A, three doses were selected for part B to evaluate the safety, tolerability, and pharmacokinetics of IMU-856 once daily for 14 days using the same randomisation algorithm. Part C enrolled patients with well controlled coeliac disease. Participants were centrally randomised 1:1:1 using an interactive web response system to receive either low dose or high dose of IMU-856 or placebo once daily for 28 days that included a 15-day gluten challenge starting on day 14. The primary objective was safety and tolerability of IMU-856. Safety analyses were done on all patients who received at least one dose of the study drug. The trial is registered with the ANZCTR registry (ACTRN12620000901909).

Findings

Between July 27, 2020, and Oct 28, 2022, 71 healthy participants were enrolled in part A and B and assigned to either placebo (n=19) or IMU-856 (n=52). In part A and B, the IMU-856 doses were 10 mg (n=6), 20 mg (n=6), 40 mg (n=13), 80 mg (n=12), 120 mg (n=4), 160 mg (n=11). 43 patients with coeliac disease were enrolled in part C and assigned to either placebo (n=14), IMU-856 80 mg (n=14), or IMU-856 160 mg (n=15). Treatment-emergent adverse events (TEAEs) occurred in 24 (73%) of 33 participants in part A and 15 (79%) of 19 participants in part B receiving any dose of IMU-856 compared with six (50%) of 12 participants in part A and five (71%) of seven participants in part B with placebo. TEAEs were mainly mild in severity. In part C, TEAEs occured in 26 (90%) of 29 patients on any dose of IMU-856 and ten (71%) of 14 receiving placebo; the most common TEAEs with any dose of IMU-856 by preferred term were headache (13 [45%] of 29), nausea (nine [31%]), diarrhoea (eight [28%]), and abdominal distension (seven [24%]). Two serious adverse events occurred with IMU-856 treatment (one in part B [bacterial myocarditis] and one in part C [biliary colic]), both of which were unrelated to IMU-856. No dose-limiting toxicities, systematic safety laboratory changes, or deaths occurred during the study. In part C, mean decrease in villous height was –20·9 μm (SD 34·8) among patients who received IMU-856 80 mg, –22·5 μm (51·1) among those who received IMU-856 160 mg, and –60·3 μm (52·2) among those who received placebo.

Interpretation

The favourable safety profile, along with preliminary activity, suggests that IMU-856 should be studied in future trials of coeliac disease.

Funding

Immunic Australia.