The biotech announced Wednesday that patients on ION224 had histologic improvement in the liver disease without worsening of fibrosis. Ionis’ mid-stage win comes as the FDA is set to decide whether to approve rival Madrigal’s resmetirom by Thursday.
Pictured: Illustration depicting a damaged liver/iStock, Mohammed Haneefa Nizamudeen
A Phase II clinical trial of Ionis Pharmaceuticals’ metabolic dysfunction-associated steatohepatitis drug candidate has hit its primary endpoint, the company said Wednesday.
Investigators randomized 160 people with metabolic dysfunction-associated steatohepatitis (MASH), the liver disease formerly known as nonalcoholic steatohepatitis, to receive placebo or one of three doses of ION224 subcutaneously once a month. Ionis designed the ligand-conjugated antisense medicine to cut production of DGAT2, an enzyme that studies have linked to fatty liver disease.
After 51 weeks, the proportion of patients who had MASH histologic improvement without worsening of fibrosis was significantly higher in the top two dose cohorts than in the placebo group. The significant differences caused the trial to meet its primary endpoint.
Ionis shared the p values for the successful 90-mg and 120-mg doses—0.015 and less than 0.001, respectively—but is yet to provide a closer look at the primary endpoint data. Subgroup analyses found patients with both F2 and F3 fibrosis, the middle scores on a four-point scarring severity scale, improved after taking ION224.
The biotech published some secondary endpoint data. ION224 beat placebo on an endpoint that looked at MASH resolution without worsening of fibrosis, as measured by biopsy. At the highest dose, 44% of patients had a 50% or greater relative reduction in liver steatosis, as measured by imaging, while 3% of people on placebo experienced such an improvement.
Ionis also saw a trend favoring ION224 for a liver scarring endpoint. In the high-dose arm, 32% of people had at least a one stage improvement in fibrosis without worsening of steatohepatitis as measured by biopsy, compared to 12.5% of their peers in the placebo cohort.
The FDA asks sponsors to show a one stage improvement in fibrosis with no worsening of MASH or the resolution of MASH with no worsening of fibrosis in Phase III clinical trials. The first wave of MASH assets failed to clear that bar but recent studies have fared better, with Madrigal Pharmaceuticals hitting both the endpoints in Phase III. The FDA is set to decide whether to approve Madrigal’s resmetirom by Thursday.
The success of resmetirom, a THR-β agonist, in clinical trials is part of a series of events that suggest Ionis will face competition if it delivers its own pivotal study victory and brings ION224 to market. Companies are working on MASH molecules against a range of targets, from Boehringer Ingelheim’s glucagon/GLP-1 receptor dual agonist survodutide to Akero Therapeutics’ FGF21 analog efruxifermin.
Other companies are interested in Ionis’ MASH target, DGAT2. Pfizer axed one DGAT2 inhibitor after Phase I but still has another candidate, PF-06865571, in mid-stage development. Data from the Phase II clinical trial are imminent, according to ClinicalTrials.gov. Other companies including Sinew Pharma and Viking Therapeutics are working on DGAT1 inhibitors.
Nick Paul Taylor is a freelance pharmaceutical and biotech writer based in London. He can be reached on LinkedIn.
