Audentes Therapeutics Announces FDA Clearance of Investigational New Drug Application for AT342 to Treat Crigler-Najjar Syndrome

SAN FRANCISCO, Feb. 1, 2017 /PRNewswire/ -- Audentes Therapeutics, Inc. (Nasdaq: BOLD), a biotechnology company focused on developing and commercializing gene therapy products for patients living with serious, life-threatening rare diseases, today announced that the U.S. Food and Drug Administration (FDA) has cleared the investigational new drug (IND) application for AT342, the Company's gene therapy product candidate to treat Crigler-Najjar Syndrome. The IND is now active and Audentes plans to initiate VALENS, the multicenter, multinational, open-label, ascending dose phase 1/2 clinical study of AT342. Preliminary data from VALENS is expected to be available by the end of 2017.

"We are pleased to achieve this important milestone and look forward to working with regulatory authorities and the medical and patient communities to evaluate AT342 for the treatment of this serious, life-threatening disease," stated Matthew R. Patterson, President and Chief Executive Officer of Audentes Therapeutics. "Based on our thorough preclinical investigation, we believe that AT342 has the potential to provide a significant and durable reduction in serum bilirubin levels, to reduce or eliminate the need for daily phototherapy treatment, to decrease the risk of devastating neurological injury, and to significantly improve the quality of life for Crigler-Najjar patients and their families."

In addition to VALENS, Audentes plans to imminently begin LUSTRO, a clinical assessment and run-in study. LUSTRO is designed to enroll 16 to 18 Crigler-Najjar patients greater than one year of age and to characterize their disease course, natural history, bilirubin variability and phototherapy usage. The study is intended to identify patients for potential enrollment in VALENS and to serve as a within-patient control for VALENS.

AT342 has been developed in collaboration with the University of Pennsylvania (Penn) under the leadership of James M. Wilson, M.D., Ph.D., a pioneer in human gene therapy and the director of the Gene Therapy Program and the Orphan Disease Center at the Perelman School of Medicine.  As part of the collaboration, Penn has licensed certain Penn-owned AAV technologies to Audentes, including rights related to AT342.

Editor's Note: Dr. Wilson reports no direct financial conflict of interest related to Audentes.  

About AT342 to treat 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 and risk of irreversible neurological damage and death.  The current standard of care for Crigler-Najjar Syndrome is 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. 

About VALENS, the Phase 1/2 clinical study of AT342
VALENS is designed as a multicenter, multinational, open-label, ascending dose study to evaluate the safety and preliminary efficacy of AT342 in approximately 12 Crigler-Najjar patients greater than or equal to one year of age. The study is expected to include nine AT342 treated subjects and three delayed-treatment concurrent control subjects. 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).  Secondary endpoints include the proportion of subjects successfully weaned off phototherapy, and UGT protein expression, DNA and RNA levels from liver biopsy at 24 weeks. Subjects are expected to remain on prescribed phototherapy for 12 weeks following administration of AT342.  Subjects with a meaningful decrease in bilirubin at week 12 will be weaned off phototherapy over a five-week period, starting in week 13 and ending during week 17. The primary efficacy analyses are expected to be conducted at the 12 and 18 -week time points. Subjects are expected to be followed for a minimum of five years to assess long term safety and durability of effect.

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 have four products in development, AT132 for the treatment of X-Linked Myotubular Myopathy (XLMTM), 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 Statements
This 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 expectations for the design and initiation of LUSTRO and VALENS, and the timing of preliminary data from each study, respectively; the ability of LUSTRO to identify patients for VALENS and to serve as a run-in study and within-patient control for VALENS; and, our belief that AT342 has the ability to durably reduce serum bilirubin levels, reduce or eliminate the need for daily phototherapy, decrease the risk of devastating neurological injury and significantly improve the lives of patients and their families. 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:
Thomas Soloway, CFO
415.818.1040
[email protected]

Media Contact:
Jeffrey Gruis
415.818.1015
[email protected]

SOURCE Audentes Therapeutics, Inc.