Regenxbio said today it will acquire Dimension Therapeutics, in an approximately $85 million deal that will expand the buyer’s adeno-associated virus (AAV) gene therapy pipeline for metabolic diseases with two lead product candidates.
The deal will add Dimension’s DTX301 and DTX401 candidates to Regenxbio’s pipeline. DTX301 is a gene therapy candidate for ornithine transcarbamylase (OTC) deficiency that uses Regenxbio’s novel AAV (NAV®) AAV8 vector to deliver a copy of the OTC gene to liver cells. DTX301 is being studied in a Phase I/II clinical trial following FDA approval of its Investigational New Drug (IND) application last year.
DTX401 is a gene therapy candidate for glycogen storage disease type Ia (GSDIa), in which an NAV AAV8 vector is used for delivering a copy of the glucose-6-phosphatase (G6Pase) gene to liver cells. An IND application is expected to be filed for DTX401 in early 2018, Regenxbio and Dimension said.
Both DTX401 and DTX301 have been designated as orphan drugs in the U.S. and Europe—and both have been developed under exclusive licenses previously granted to Dimension by Regenxbio.
NAV includes novel AAV vectors such as rAAV7, rAAV8, rAAV9, and rAAVrh10. According to Dimension, NAV provides further advantages over traditional AAV vectors, including greater efficiency for delivering genes in vivo, faster onset of gene expression, high tissue selectivity, and high-titer manufacture.
The technology was discovered in the lab of Regenx’ scientific founder James M. Wilson, M.D., Ph.D., director of the gene therapy program at the University of Pennsylvania. Dr. Wilson also chairs Dimension’s Scientific and Technical Advisory Board, and serves as clinical development editor of Human Gene Therapy, a journal published by GEN publisher Mary Ann Liebert Inc.
Hemophilia B Failure
The acquisition comes three months after Dimension halted development of DTX101, a AAVrh10-based gene therapy candidate for moderate/severe-to-severe hemophilia B, after disappointing Phase I/II data convinced the company that it would not meet the minimum target product profile for continued development or future commercialization.
However, the deal will add to Regenxbio’s pipeline Dimension’s DTX201, a gene therapy candidate for hemophilia A that is being developed and commercialized through an up-to-$252 million collaboration with Bayer launched in 2014. DTX201 is designed to use Regenxbio’s NAV technology to deliver a copy of the Factor VIII gene to liver cells. An IND application is anticipated to be filed for DTX201 in early 2018.
In addition, the deal includes Dimension’s preclinical product candidates for phenylketonuria (PKU), Wilson disease, and citrullinemia type I, as well as manufacturing technology and other intellectual property.
“This acquisition confirms Regenxbio’s leadership in the field of AAV gene therapy and expands our pipeline in metabolic diseases using NAV Technology with a clinical asset and several preclinical assets,” Regenxbio CEO Kenneth T. Mills said in a statement. “Regenxbio has the resources and expertise to be successful in advancing a portfolio of gene therapies for inherited metabolic diseases targeting the liver.”
Mills added that DTX301 and DTX401 will join a Regenxbio pipeline with potential to achieve multiple milestones through the end of next year, starting with interim updates anticipated for the end of this year on RGX-314 for wet age-related macular degeneration (AMD) and RGX-501 for homozygous familial hypercholesterolemia (HoFH).
“The acquisition of Dimension is another meaningful step in building a robust clinical pipeline of gene therapy product candidates with the goal of improving treatment options for patients and families in many diseases,” Mills added.
Added Dimension CEO Annalisa Jenkins, MBBS, FRCP: “Regenxbio has strong leadership, understanding of technology, capabilities, and financial resources that provide significant synergies with Dimension’s R&D portfolio. We are pleased that this transaction provides an opportunity for Dimension shareholders to participate in the future success of what we believe will be an industry-leading gene therapy pipeline.”
Dimension would become a wholly owned subsidiary of Regenxbio following the deal, in which Regenxbio plans to acquire Dimension for approximately $3.41 per share in an all-stock transaction. According to NASDAQ, where company shares are traded on the NASDAQ Global Select Market, Dimension has 24,879,574 shares outstanding—which would value the acquisition deal at $84.8 million.
The boards of both companies have unanimously approved the deal, which is expected to close by the end of this year, subject to approval by Dimension shareholders, required customary regulatory approvals, and satisfaction of other customary closing conditions.