TWi Biotechnology Announces Completion of Primary Endpoint Assessment in Global Phase 2/3 Pivotal Trial of AC-203; Q4 Unblinding Countdown Begins as Company Aims to Deliver the World’s First Treatment for EBS

Taipei, June 15, 2026 — TWi Biotechnology, Inc. (6610) today announced that AC-203, its investigational drug for the treatment of Epidermolysis Bullosa Simplex (EBS), has completed the Primary Endpoint Assessment for the last enrolled patient in its global Phase 2/3 pivotal trial, the EBShield Study, marking a major milestone in the product’s clinical development.

The study has completed the planned primary efficacy assessment for all enrolled patients, with topline results expected to be announced in the fourth quarter of 2026. If the trial meets its primary efficacy endpoint, AC-203 has the potential to become the first approved treatment for EBS worldwide, addressing a significant unmet medical need.

The EBShield Study is a global, multinational, multicenter, randomized, double-blind, placebo-controlled pivotal clinical trial. A total of 81 patients were enrolled across 37 clinical trial sites in 19 countries. The study design includes a double-blind efficacy assessment period followed by an open-label safety follow-up period. The efficacy assessment period has now been fully completed, and long-term safety data will continue to be collected to support future global regulatory submissions.

“Completion of the Primary Endpoint Assessment for all patients means that the global development program for AC-203 has entered its final stage,” said Chen-En Tsai, President and Chief Medical Officer of TWi Biotechnology. “From early research and clinical proof-of-concept to the global pivotal trial, our team has continued to advance the development of AC-203 with the goal of providing EBS patients with the first clinically meaningful treatment option. We look forward to the topline results in the fourth quarter and are advancing our commercialization and licensing plans in parallel.”

Dr. Tsai further noted that EBS is a rare genetic skin disorder in which genetic defects cause the skin to become extremely fragile, resulting in recurrent blisters, wounds, and chronic inflammation. There are currently no approved therapies specifically indicated for the treatment of EBS anywhere in the world. Clinical management remains primarily focused on supportive care and symptom control, underscoring the high unmet medical need in this patient population.

AC-203 is a topical dermatologic drug containing diacerein as its active ingredient. It is intended to improve recurrent blistering and related symptoms caused by skin fragility and chronic inflammation in patients with EBS, with the goal of effectively reducing both the frequency and severity of blister formation. AC-203 has been granted Orphan Drug Designation, Fast Track Designation, and Rare Pediatric Disease Designation by the U.S. Food and Drug Administration (FDA). It has also received orphan drug designation from the European Medicines Agency (EMA) and Taiwan Food and Drug Administration (TFDA).

In addition, AC-203 is eligible to apply to the U.S. FDA for a Rare Pediatric Disease Priority Review Voucher (RPD-PRV). If granted in the future, the voucher may be transferable in the market. In recent years, similar voucher transactions have generally ranged from approximately US$100 million to US$200 million, representing significant commercial value.

As the unblinding timeline approaches, TWi Biotechnology is also advancing its global and regional commercialization strategy. The Company is currently in close discussions with multiple international pharmaceutical companies regarding licensing collaborations and market expansion models. Through strategic commercialization partnerships, the Company aims to accelerate the future launch of AC-203 in global markets.

TWi Biotechnology will continue to focus on rare diseases and areas with significant unmet medical needs. Through innovative development strategies, the Company is committed to maximizing product value and creating long-term value for patients, partners, and shareholders.