WILMETTE, Ill., May 19, 2026
Monopar Therapeutics announced the publication of new Phase 2 clinical trial data showing that ALXN1840 (tiomolibdate choline) achieved a rapid, statistically significant, and sustained improvement in copper balance in patients with Wilson disease, a rare genetic disorder that causes toxic copper accumulation in the body. The peer-reviewed study was published in Hepatology Communications and evaluated the drug’s ability to increase copper elimination through fecal excretion while improving overall copper regulation in patients who had already undergone years of standard treatment.
The open-label, single-arm Phase 2 ALXN1840-WD-204 trial enrolled nine Wilson disease patients across clinical centers in the United Kingdom and New Zealand. Researchers monitored patients under controlled dietary conditions before and after treatment initiation with daily ALXN1840 dosing. According to the published data, the investigational therapy demonstrated a statistically significant reduction in daily copper balance, driven primarily by increased fecal copper excretion. Investigators reported a cumulative mean decrease from baseline in copper balance of -6.08 mg over 21 days, alongside a roughly 50% increase in the daily fecal copper output-to-intake ratio compared to baseline levels.
ALXN1840 Demonstrates Rapid Copper Mobilization in Wilson Disease
Wilson disease occurs when the body cannot properly remove excess copper, leading to toxic accumulation in critical organs such as the liver and brain. Despite long-term use of currently approved therapies, many patients continue to retain residual copper burden that contributes to progressive organ damage. The newly published study suggests that ALXN1840 may address this unmet need by mobilizing and eliminating copper more effectively than existing treatments.
Researchers observed immediate increases in plasma total copper and directly measured non-ceruloplasmin-bound copper (dNCC) following treatment initiation, findings consistent with active copper mobilization and formation of stable copper-binding complexes. Importantly, the study population had an average prior standard-of-care treatment duration of approximately 16 years, indicating that substantial residual copper remained despite prolonged therapy. Investigators noted that ALXN1840 was able to successfully mobilize and remove this excess copper, reinforcing earlier findings from the company’s completed 48-week Phase 3 trial, where the drug demonstrated superior copper mobilization compared with standard therapies.
The publication also highlighted the importance of evaluating Wilson disease therapies against pre-treatment baseline measurements rather than relying solely on comparisons with ongoing standard-of-care treatment. Investigators stated that this methodology provides a clearer understanding of how effectively a therapy changes copper balance and supports more accurate assessment of clinical benefit in Wilson disease patients.
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Phase 2 Results Support Potential New Treatment Option
According to the study findings, ALXN1840 produced a mean daily copper balance change from baseline of -0.37 mg during the 15 mg/day treatment period, with statistical significance maintained throughout the overall study period. Researchers emphasized that the improvements were both rapid and sustained, suggesting the therapy may offer a meaningful advancement in copper management for Wilson disease patients.
The treatment was also reported to be generally well tolerated, with no serious adverse events observed during the trial. Safety findings were considered favorable given the chronic nature of Wilson disease treatment and the long-term management requirements associated with the condition.
Professor Aftab Ala, Consultant Hepatologist at King’s College London and lead author of the publication, stated that the data reinforce ALXN1840’s promise as a potentially important new treatment option for Wilson disease patients. He noted that the therapy’s ability to rapidly improve copper balance highlights its potential clinical value for patients who continue to experience residual copper accumulation despite years of existing treatment.Hepatology Communications published the findings as interest continues to grow around next-generation therapies targeting rare metabolic and genetic liver diseases.
Source: Monopar Therapeutics press release
