BOSTON– Eccogene announced that the first patient has been enrolled in its Phase 2a clinical trial evaluating ECC4703 in combination with semaglutide for the treatment of obesity.
The study, known as MIST, will assess whether ECC4703 can provide additive or synergistic benefits when used alongside a GLP-1 receptor agonist. Participants in the trial will receive weekly injectable semaglutide along with either oral ECC4703 or a placebo once daily over a 12-week treatment period.
The trial will evaluate the contribution of ECC4703 to weight loss and other pharmacodynamic measures during the study period.
“We are pleased to advance ECC4703 into this Phase 2a study in obesity,” said Jingye Zhou, Chief Executive Officer of Eccogene. “While GLP-1–based therapies have established a new standard of care, important questions remain regarding tolerability, body composition, and overall quality of weight loss. Our preclinical data suggest ECC4703 may contribute to deeper weight reduction driven primarily by fat mass loss over lean mass loss, and, to our knowledge, we are one of the first in the industry to test this hypothesis in a robustly designed clinical trial.”
The multicenter, randomized, double-blind, placebo-controlled trial is expected to enroll approximately 160 adults with obesity.
Primary endpoints include changes in body weight and liver fat content measured using MRI-PDFF imaging. Secondary and exploratory endpoints will examine additional metabolic parameters along with safety and tolerability.
“Obesity is not a single-pathway disease, and for many patients, monotherapy simply doesn’t address the full metabolic burden,” said Julio Rosenstock, MD, Lead Investigator and Eccogene’s Senior Scientific Advisor. “By combining semaglutide with ECC4703, a selective thyroid hormone receptor-beta agonist designed to act in the liver, we’re exploring whether a dual-mechanism approach can meaningfully enhance metabolic control—particularly by further reducing liver fat—beyond what GLP-1 therapy alone can achieve.”
ECC4703 is an oral, once-daily therapy designed as a selective full agonist of thyroid hormone receptor beta (THR-β) that primarily targets the liver. The therapy is being developed for metabolic dysfunction-associated steatohepatitis and other cardiometabolic diseases.
In Phase 1 studies, the drug demonstrated target engagement and statistically significant reductions in LDL cholesterol and related lipid biomarkers, supporting its potential to address underlying metabolic drivers across multiple metabolic conditions.
