• The primary endpoint of copper control was met in 79% of patients (p<0.001)
• Mean reduction of serum free copper levels was 77% (p<0.0001)
• Significant improvements in neurological status (p<0.0001) and patient reported disability (p<0.001) were demonstrated
• Liver status was stabilized or improved over the treatment period in the majority of patients
• WTX101 was generally well tolerated, with no reported cases of an initial drug-induced neurological worsening upon treatment initiation
Wilson Therapeutics AB (publ), announced today that the Phase 2 study of WTX101 (bis-choline tetrathiomolybdate; Decuprate®), an investigational first in class copper modulating agent with a unique mode of action for the treatment of patients with Wilson Disease, met its primary endpoint. In the ITT population, 79% of patients achieved or maintained normalized levels of free copper, or experienced a reduction of at least 25% in free copper in blood from baseline, after 24 weeks of treatment with WTX101.
The Phase 2 study WTX101-201 was a 24-week open-label multicenter study evaluating the efficacy and safety of WTX101 monotherapy in 28 newly-diagnosed patients with Wilson Disease who had received either no prior treatment for Wilson Disease or a standard of care agent for up to two years. All patients who successfully completed the 24-week study period elected to stay on WTX101 in an extension phase of the study.
In the ITT population, WTX101 monotherapy reduced mean serum free copper by 77% (p<0.0001) at week 24 compared to baseline. WTX101 treatment also resulted in improvements in neurological status (p<0.0001) and disability (p<0.001) measured as a change from baseline in Unified Wilson Disease Rating Scale (UWDRS) Part 3 and Part 2 respectively. In addition, liver status, as measured by the Modified Nazer Score, was stabilized or improved in the majority of patients.
Treatment with WTX101 was generally well tolerated with most reported adverse events being mild (grade 1) to moderate (grade 2). Reversible liver test elevations were observed in 39% of patients and these elevations were generally mild to moderate, asymptomatic and normalized with dose adjustments. No initial drug-induced neurological worsening was observed upon treatment initiation with WTX101. In total, six patients discontinued the study, including three related to adverse events. Detailed data from the WTX101-201 study will be presented at upcoming medical meetings.
“Final data from the Phase 2 study demonstrate that WTX101 has the potential to rapidly lower and control free copper, and improve or stabilize neurological and liver status in patients with Wilson Disease. We are also very pleased the treatment improved the patients’ self-reported disability and that we have not observed any case of initial neurological worsening upon initiation of WTX101. Additionally, the data continue to show that WTX101 is generally well-tolerated with few patients reporting GI intolerance or skin reactions. We believe that this therapeutic profile, with the convenience of once-daily dosing, could translate into improved treatment adherence and outcomes”, commented Carl Bjartmar, MD, PhD, Chief Medical Officer of Wilson Therapeutics.
“We are extremely pleased with the results from this Phase 2 study. We believe that WTX101 may have the potential to improve treatment options for patients with Wilson Disease, a life-long disease for which there has been no innovation for decades. We will now focus on agreeing the final Phase 3 program with relevant regulatory authorities, and expect to initiate a pivotal Phase 3 study in 2017”, said Jonas Hansson, Chief Executive Officer of Wilson Therapeutics.
A web-cast telephone conference will be held on December 5 at 15.00 CET where the topline data will be presented by CEO Jonas Hansson and CMO Carl Bjartmar. The webcast, and later the recorded version of the webcast and the conference call, will also be accessible via Wilson Therapeutics’ website.
WTX101-201 is a 24-week open-label Phase 2 study evaluating the efficacy and safety of WTX101 monotherapy in 28 newly-diagnosed patients with Wilson Disease, aged 18 years and older, who had received either no prior treatment for Wilson Disease or a standard of care agent for up to two years. Patients recruited in the study had various degrees of hepatic impairment at the time of enrollment and the majority also had neurological symptoms at study start. The study was conducted at 11 sites in the U.S. and Europe. Patients received WTX101 at individualized doses between 15 and 120 mg/day. The primary endpoint was defined as achieving or maintaining normalized levels of less than 2.3 µM of free blood copper, or reaching a reduction of at least 25% in free copper in blood from baseline, after 24 weeks of treatment. Free copper in blood was measured as non-ceruloplasmin bound copper, corrected for the amount of copper bound to tripartite tetrathiomolybdate-Cu-albumin complexes in blood. Secondary endpoints included reduction of serum free copper from baseline, neurological disability and status measured as Unified Wilson Disease Rating Scale (UWDRS) part 2 and 3 respectively, liver status measured as the Modified Nazer Score and quality of life measured through EuroQOL 5 Dimensions (EQ5D).
About WTX101 (bis-choline tetrathiomolybdate)
WTX101 (bis-choline tetrathiomolybdate; Decuprate®) is a first in class copper modulating agent with a unique mechanism of action, under investigation as a novel therapy for Wilson Disease. WTX101, unlike current treatments for Wilson Disease, exhibits a specific copper buffering activity and acts in the liver where it removes copper from the overloaded copper buffer. WTX101 also rapidly neutralizes toxic free copper in tissue and blood by forming complexes with excess copper and albumin. The excess copper is excreted via the bile, the body’s natural route for excess copper elimination.
The active ingredient of WTX101, tetrathiomolybdate, has been tested in several clinical studies in Wilson Disease patients and the data from these studies, as well as data from the Company’s WTX101-201 study, suggest that WTX101 can rapidly lower and control toxic free copper levels and improve clinical symptoms in these patients. The data also suggest that WTX101 is generally well-tolerated and may have potential for a reduced risk of neurological worsening after initiation of therapy. WTX101 is expected to have a once-daily dosing regimen which may potentially translate into improved compliance in Wilson Disease patients, leading to fewer treatment failures and ultimately improved outcomes as a result. WTX101 has received orphan drug designation for the treatment of Wilson Disease in the US and EU.
About Wilson Disease
Wilson Disease is a rare genetic disorder of impaired copper metabolism that causes serious copper poisoning. The genetic defect severely affects the body´s ability to regulate copper balance, resulting in life-threatening damage to the liver, the brain and further organs if left untreated. Wilson Disease affects approximately one in every 30,000 people worldwide, corresponding to a prevalence of approximately 10,000 patients in the US and 15,000 patients in the EU. The therapies currently being used in Wilson Disease were introduced in the 1950’s and 60’s and since then there have been no new treatment options developed for patients with this disease.
About Wilson Therapeutics
Wilson Therapeutics is a biopharmaceutical company, based in Stockholm, Sweden, that develops novel therapies for patients with rare diseases. Wilson Therapeutics’ lead product, WTX101, is initially being developed as a novel treatment for Wilson Disease and has been evaluated in a Phase 2 clinical study. Wilson Therapeutics is listed in the Mid Cap segment on Nasdaq Stockholm with the stock ticker WTX.
Visit www.wilsontherapeutics.com for more information.
For further information contact:
Jonas Hansson, CEO, Wilson Therapeutics AB
Telephone: +46 8 796 00 00
Wilson Therapeutics AB (publ)
Org nr 556893-0357
Västra Trädgårdsgatan 15
SE-111 53 Stockholm
The information in the press release is information that Wilson Therapeutics is obliged to make public pursuant to the EU Market Abuse Regulation. The information was submitted for publication, through the agency of the contact person set out above, at 08.00 CET on December 5, 2016.