Resolution Therapeutics has treated its last EMERALD trial patient, putting macrophage-based therapy on track for results before year’s end.
Liver transplants save lives, but there simply aren’t enough livers to go around. For patients with end-stage liver disease, that scarcity is the whole problem: transplantation is the only treatment that actually reverses the disease, yet access to it is limited by donor availability, the complexity of the surgery, and which transplant centers a patient can reach. Everyone else is left managing symptoms and hoping their liver holds.
Resolution Therapeutics, a biotech spun out of Professor Stuart Forbes’ lab at the University of Edinburgh, is trying to build something in between: a treatment that doesn’t replace the organ but helps it repair itself. On 11 September, the company announced that it had dosed the final patient in EMERALD, its Phase I/II trial of an engineered cell therapy called RTX001, in patients with end-stage liver disease and a history of decompensated cirrhosis [1].
This is where the longevity angle gets interesting. A lot of aging research focuses on slowing decline before it starts. Resolution’s approach is almost the opposite: it’s trying to restart a repair process the body has already lost the ability to run on its own. That’s a distinction worth sitting with, because organ regeneration, not just organ preservation, may end up being one of longevity medicine’s more consequential fronts.
RTX001 belongs to a category Resolution calls Regenerative Macrophage Therapy. Macrophages are immune cells that, among other jobs, help clean up damaged tissue and kick-start healing. In a healthy liver, they do this well. In a scarred, cirrhotic one, that repair signal breaks down. Resolution’s therapy engineers macrophages with two added components, IL-10 and MMP-9, aimed at boosting both their anti-inflammatory and anti-fibrotic effects, essentially trying to give the liver’s own repair crew better tools.
Fifteen patients have now been dosed in EMERALD, a multi-center, single-arm, open-label study running across hepatology centers in the UK and Spain. It’s a first-in-human study, meaning this is the earliest real-world look at how the therapy behaves in people, not just in the lab. Interim data are expected in the fourth quarter of 2026, just a few months out.
“Dosing the final patient in the EMERALD trial marks a significant milestone for Resolution Therapeutics and reflects our progress toward a potential new treatment paradigm for end-stage liver disease,” said Amir Hefni, the company’s CEO. “Patients with this condition face very limited options beyond transplantation and symptom management, and RTX001 has the potential to offer a differentiated, transformational therapeutic approach. We are working with urgency to advance the clinical program and bring this therapy closer to the patients who need it.”
The practical case for RTX001 isn’t just biological; it’s logistical. The therapy is given through a standard peripheral IV, with no pre-conditioning, bridging therapy or lymphodepletion required beforehand, and the infusion itself takes under 10 minutes as an outpatient procedure. That’s a meaningfully lighter lift than many advanced cell therapies, which can require hospitalization and weeks of preparation.
Resolution also says ongoing manufacturing refinements have already cut its cost of goods by 40%, a number that matters if this treatment is ever going to reach patients at scale rather than staying a boutique option.
The stakes are sizable. More than 500,000 people in the US currently live with end-stage liver disease, a number expected to grow to 600,000 by 2040. After a first decompensation event, the numbers get grim fast: 37% of patients die, and 5% receive a transplant within two years, and median survival drops from about two years after a first decompensation to roughly nine months after a second. Those are the patients this trial is built around.
Assuming EMERALD’s interim data hold up, Resolution says it plans to open a pivotal US study in 2027, following a pre-IND meeting with the FDA, with lung fibrosis and an in vivo version of the therapy already moving through earlier-stage work behind it.
