Audentes Therapeutics Announces MHRA Approval of Clinical Trial Authorisation Application for AT342 to Treat Crigler-Najjar Syndrome

- "This CTA approval represents an important milestone for our AT342 program," stated Matthew R. Patterson, President and Chief Executive Officer.  "We are pleased to be working closely with the European Crigler-Najjar Syndrome community as we continue to execute on our global plans to develop AT342 as a potentially transformative product to treat this devastating rare disease." In addition to VALENS, the clinical development program for AT342 includes LUSTRO, a prospective natural history run-in study.  The primary objectives of LUSTRO are to characterize the clinical condition of patients with Crigler-Najjar Syndrome, identify subjects for potential enrollment in VALENS, and serve as a longitudinal baseline and within-patient control for VALENS.   About VALENS, the Phase 1/2 Clinical Study of AT342VALENS is a multicenter, multinational, open-label, ascending dose study to evaluate the safety and preliminary efficacy of AT342 in approximately 12 Crigler-Najjar patients one year of age and older. The study is expected to include nine AT342 treated patients and three delayed-treatment concurrent control patients. Primary endpoints include safety (adverse events and certain laboratory measures, including immunological parameters) and efficacy (changes in serum bilirubin and number of hours on phototherapy within a 24-hour period).  Patients are expected to remain on prescribed phototherapy for 12 weeks following administration of AT342, and those with a meaningful decrease in bilirubin at week 12 will be weaned off phototherapy over the subsequent five-week period.  Patients are expected to be followed for a minimum of five years to assess long term safety and durability of effect. About AT342 for Crigler-Najjar Syndrome AT342 is an AAV8 vector containing a functional copy of the UGT1A1 gene for the treatment of Crigler-Najjar Syndrome, a rare monogenic disease characterized by severely high levels of unconjugated bilirubin in the blood which present a significant risk of irreversible neurological damage and death.  The current standard of care for Crigler-Najjar Syndrome is daily, persistent phototherapy, usually for longer than 12 hours per day. Phototherapy wanes in effectiveness as children age, and a liver transplant may be required for survival.  A single administration of AT342 has generated durable, dose-responsive and clinically-relevant decreases in total bilirubin levels in a mouse model of Crigler-Najjar, with no significant AT342-related adverse events or safety findings. About Audentes Therapeutics, Inc.Audentes Therapeutics (Nasdaq: BOLD) is a biotechnology company focused on developing and commercializing gene therapy products for patients living with serious, life-threatening rare diseases.  We are currently conducting a Phase 1/2 clinical study of our lead product candidate AT132 for the treatment of X-Linked Myotubular Myopathy (XLMTM) and have three additional product candidates in development, including AT342 for the treatment of Crigler-Najjar Syndrome, AT982 for the treatment of Pompe disease, and AT307 for the treatment of the CASQ2 subtype of Catecholaminergic Polymorphic Ventricular Tachycardia (CASQ2-CPVT).  We are a focused, experienced and passionate team committed to forging strong, global relationships with the patient, research and medical communities. For more information regarding Audentes, please visit www.audentestx.com. Forward Looking StatementsThis press release contains forward-looking statements within the meaning of the "safe harbor" provisions of the Private Securities Litigation Reform Act of 1995, including, but not limited to: the ability of LUSTRO to be used as a longitudinal baseline and within patient control for VALENS and the potential of AT342 to be a transformative therapy for Crigler-Najjar patients.  All statements other than statements of historical fact are statements that could be deemed forward-looking statements. Although the company believes that the expectations reflected in such forward-looking statements are reasonable, the company cannot guarantee future events, results, actions, levels of activity, performance or achievements, and the timing and results of biotechnology development and potential regulatory approval is inherently uncertain. Forward-looking statements are subject to risks and uncertainties that may cause the company's actual activities or results to differ significantly from those expressed in any forward-looking statement, including risks and uncertainties related to the company's ability to advance its product candidates, obtain regulatory approval of and ultimately commercial its product candidates, the timing and results of preclinical and clinical trials, the company's ability to fund development activities and achieve development goals, the company's ability to protect intellectual property and other  risks and uncertainties described under the heading "Risk Factors" in documents the company files from time to time with the Securities and Exchange Commission. These forward-looking statements speak only as of the date of this press release, and the company undertakes no obligation to revise or update any forward-looking statements to reflect events or circumstances after the date hereof. Audentes Contacts: Investor Contact:Andrew Chang, Investor [email protected] Media Contact:Paul [email protected] Logo - https://mma.prnewswire.com/media/602363/Audentes_Therapeutics___Logo.jpg