Wilson Therapeutics to present data from WTX101 Phase 2 extension study at 4th Congress of the European Academy of Neurology

Jun 01, 2018

Wilson Therapeutics AB (publ) announces that it will present preliminary data from the ongoing extension of the company’s Phase 2 trial of WTX101 (bis-choline tetrathiomolybdate), an investigational first-in-class copper-protein-binding agent under investigation as a novel therapy for Wilson Disease, at the 4th Congress of the European Academy of Neurology (EAN), in Lisbon, Portugal, June 16 – 19, 2018.

As previously reported and highlighted in the EAN abstract which is available online today, data from the study support that the initial improvements in free copper levels and hepatic status observed at week 24 and 48 were preserved or further improved at 72 weeks. Specifically, the improvements in neurological score (UWDRS part 3) and disability (UWDRS part 2) seen after 24 and 48 weeks continued and were further improved following once-daily treatment with WTX101 for 72 weeks.

Presentation details
Presentation number: EPR1075

Title: WTX101 – A Novel Copper-Protein-Binding Agent for Wilson Disease Demonstrates Long-Term Neurological Improvement in an Ongoing Extension of a Phase 2 study (WTX101-201)

Authors:  A. Czlonkowska (Institute of Psychiatry and Neurology, Warsaw/Poland), M. Schilsky (Yale University Medical Center, New Haven/USA), F. Askari (University of Michigan Hospital, Ann Arbor/USA), P. Ferenci (Medical University of Vienna, Vienna/Austria), J. Bronstein (University of California, Los Angeles/USA), D. Bega (Northwestern University, Chicago/USA), A. Ala (The Royal Surrey County Hospital NHS Foundation Trust, Guildford/UK), D. Nicholl (Sandwell and West Birmingham Hospitals NHS Trust, Birmingham/UK), K. H. Weiss (University Hospital Heidelberg)

Date: Saturday, June 16

Session details: Movement disorders 3; 13:30 – 14:15 CET; Screen B10 in the Poster Area

The abstract can be accessed via the conference website at www.ean.org/lisbon2018.

About the Phase 2 study
WTX101-201 was 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 US 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-copper-albumin complexes formed during WTX101 treatment (NCCcorrected). Secondary endpoints included reduction of serum free copper from baseline, neurological disability and status measured as Unified Wilson Disease Rating Scale (UWDRS) part II and III respectively, liver status measured with the Modified Nazer Score and quality of life measured with the EuroQOL 5 Dimensions Visual Analogue Scale (EQ VAS). A 36-month extension phase of the study is ongoing.

About WTX101 (bis-choline tetrathiomolybdate)
WTX101 (bis-choline tetrathiomolybdate) is a first-in-class copper-protein-binding agent with a unique mechanism of action, under investigation as a novel therapy for Wilson Disease. In contrast to current treatments, WTX101 provides an alternative copper-protein binding mechanism by forming a tripartite complex with copper and albumin. WTX101 thereby detoxifies excess copper in both liver and blood, and promotes copper clearance through biliary excretion (the body’s natural route of elimination).

A Phase 2 study evaluating the efficacy and safety of WTX101 in patients with Wilson Disease has successfully been completed. In addition, the active moiety of WTX101, tetrathiomolybdate, has been tested in several previous clinical studies in Wilson Disease patients. The data from these studies suggest that WTX101 can reduce and control free copper levels and improve symptoms and associated disabilities. The data also suggest that WTX101 is generally well tolerated with a low risk of drug-induced neurological worsening. The tolerability profile and the expected once-daily dosing regimen have the potential to improve compliance in Wilson Disease patients, leading to fewer treatment failures and ultimately improved outcomes. WTX101 has received Fast Track designation in the US and orphan drug designation for the treatment of Wilson Disease in the US and EU.

In addition, WTX101 has shown potential as a treatment for several other medical conditions including Amyotrophic Lateral Sclerosis (ALS). WTX101 has received US orphan drug designation for the treatment of ALS.

About Wilson Disease
Copper is an essential trace element that plays a critical role in key physiological cellular processes. Due to its toxic potential, copper is normally tightly bound to copper-carrying proteins inside the liver, and excess copper is eliminated from the body via biliary excretion. Wilson Disease is a rare genetic disorder of impaired copper transport and excretion, caused by loss of function of the ATP7B copper-binding protein. This leads to copper overload in the liver, release of free copper into the blood, and damaging accumulation of copper in the brain and other organs. Untreated Wilson Disease inevitably leads to various combinations and severity of hepatic, neurologic and psychiatric symptoms, and is ultimately fatal.

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 1950s and 60s. Since then, no new treatment options have been developed and considerable unmet medical needs still exist.

About Wilson Therapeutics
Wilson Therapeutics is a biopharmaceutical company, based in Stockholm, Sweden, that develops novel therapies for patients with rare copper-mediated disorders. Wilson Therapeutics’ lead product, WTX101, is in Phase 3 development as a novel treatment for Wilson Disease. Wilson Therapeutics is listed in the Mid Cap segment on Nasdaq Stockholm with the stock ticker WTX. On April 11 2018, Alexion announced a public offer to the shareholders in Wilson Therapeutics. This offer was declared unconditional on May 25, 2018 and the company has applied for delisting from Nasdaq Stockholm.

Visit www.wilsontherapeutics.com for more information.

For further information please contact:

Jonas Hansson, CEO, Wilson Therapeutics AB
Phone:    +46 8 796 00 00
E-mail:    jonas.hansson@wtx.se

Lauren Williams, Head of Investor Relations, Wilson Therapeutics AB
Phone:    +44 7958 669 896
E-mail:    lauren.williams@wtx.se

Wilson Therapeutics AB (publ)
Corp. Reg. No.556893-0357
Kungsgatan 3
SE-111 43 Stockholm