Stoke Therapeutics Secures $90 Million Series B Financing to Advance Antisense Oligonucleotide Pipeline for Severe Genetic Disorders

On October 24, 2018, VCBeat (WeChat ID: VCbeat) learned that biotechnology company Stoke Therapeutics had completed a $90 million Series B financing round. The round was led by RTW Investments, with participation from founding investor Apple Tree Partners and new investors RA Capital Management, Cormorant Asset Management, and Perceptive Advisors. The fund managers for this round included Janus Henderson Investors, Redmile Group, Sphera Funds Management, and Alexandria Venture Investments. Additionally, Dr. Roderick Wong of RTW Investments, Dr. Matthew Hammond of RA Capital, and Mr. Bihua Chen of Cormorant Asset Management will join the Board of Directors as observers.

Stoke intends to use the funding to advance its antisense oligonucleotide drug pipeline for Dravet syndrome—a rare, catastrophic, and treatment-resistant epilepsy that begins in infancy—and other severe genetic disorders.

Stoke has pioneered a unique therapeutic platform, TANGO, which utilizes antisense oligonucleotides to enhance the expression of proteins with reduced function in genetic disorders. By modulating RNA splicing, a key step in gene expression, this approach increases the production of messenger RNA available for translation into protein. The technology was developed in collaboration with scientific founder Dr. Adrian Krainer of Cold Spring Harbor Laboratory, an expert in RNA splicing and the inventor of SPINRAZA® (nusinersen), a recently approved antisense therapy. Stoke has secured exclusive licenses from Cold Spring Harbor Laboratory and the University of Southampton for patents related to TANGO and is actively advancing a drug candidate for the treatment of Dravet syndrome, with clinical trials expected to commence in 2020.

This drug candidate upregulates the protein deficient in patients with Dravet syndrome by targeting RNA splicing. Administered via intrathecal injection, this antisense oligonucleotide therapy is given once every four months. Stoke has also established a robust pipeline of drug candidates for the treatment of other diseases affecting the central nervous system, eyes, ears, liver, and kidneys.

Stoke's R&D Pipeline

Since its inception, Stoke has validated target genes for hundreds of diseases. These targets can be prioritized in tissues amenable to retrograde delivery—including the central nervous system, eyes, and liver—by upregulating them via its proprietary TANGO (Targeted Augmentation of Nuclear Gene Output) platform. Although Stoke initially focused on genetic disorders caused by loss-of-function mutations in single genes, its TANGO platform can also reverse disease progression or prevent disease by targeting and enhancing the expression of non-mutated genes.

In January 2018, Stoke secured a $40 million Series A financing round from Apple Tree Partners to advance its multiple preclinical R&D programs.

Edward M. Kaye, M.D., CEO of Stoke Therapeutics, stated: “Our technology was initially developed to investigate the genetic underpinnings of conditions such as Dravet syndrome, aiming not merely to alleviate symptoms but to prevent the long-term disabling sequelae of these diseases. We are delighted to have the support of this distinguished group of cross-sector investors, which will help accelerate the progress of our clinical trials.”

Stoke Therapeutics, founded in 2018 and headquartered in Bedford, Massachusetts, USA, is dedicated to increasing gene expression to treat severe genetic diseases affecting the eyes, ears, liver, and kidneys of the central nervous system. Stoke's technology is the first gene-specific disease-modifying approach to prevent seizures and reduce developmental deficits.