Kate Therapeutics launches with $51M to develop genetic medicines for muscle and heart diseases

Gene therapy company Kate Therapeutics Inc. (KateTx), has emerged from stealth mode with a $51 million Series A financing.

In addition, the company has granted Astellas Pharma Inc. an exclusive, worldwide license to develop, manufacture and commercialize KT430 to treat X-linked myotubular myopathy (XLMTM).

There are a large number of genetically defined and complex muscle and heart diseases that cannot currently be addressed due to a lack of specific and effective delivery to these tissues. Adeno-associated virus (AAV)-based capsids have shown promise to deliver therapeutic cargoes in other organs, but have been hampered for use in muscle and heart by limited potency, lack of tissue selectivity and minimal regulation of cargoes.

“We are excited to announce KateTx’s launch and what this means for patients suffering from muscle and heart diseases,” said Kevin Forrest, president, CEO and a director of KateTx. 

“KateTx is applying novel capsid and cargo technology platforms to enable skeletal and cardiac muscle targeting and liver de-targeting. We believe our technologies can provide safer and more effective medicines for patients.”

Proceeds from the financing and license agreement will support the advancement of KateTx’s initial internal portfolio of muscle and heart disease programs, including myotonic dystrophy type 1 (DM1) and facioscapulohumeral muscular dystrophy (FSHD), which are two of the leading causes of adult-onset muscular dystrophy.

About DM1 and FSHD

Myotonic dystrophy type 1 is a progressive multisystem disorder affecting approximately 40,000 individuals in the U.S. Common symptoms include weakness and myotonia (inability to relax muscles) of the lower legs, hands, neck and face, causing upper extremity disability and difficulty walking, and extramuscular symptoms including cognitive problems, daytime sleepiness and sleep disturbance, and arrhythmias. Adult-onset forms are the most common; child-onset and congenital forms are more severe and sometimes life-threatening. There are no approved medicines for DM1.

Facioscapulohumeral muscular dystrophy is a heritable muscle disorder that also affects approximately 40,000 people in the U.S. FSHD onset is typically 15 to 30 years of age. Weakness usually progresses in a descending pattern, affecting the face, shoulders and upper arms, lower legs and hips. Upper extremity weakness is often most pronounced, but many patients will have significant difficulty walking, and about 20% eventually require a wheelchair. There are no approved medicines for FSHD.

Kate Therapeutics‘ differentiated delivery approach

For capsids, KateTx’s DELIVER platform leverages directed evolution, RNA-based selection of functional capsid variants and machine learning in various in vivo models. The platform already has yielded the MyoAAV class of capsids, which were developed by KateTx scientific co-founder and chief scientific officer Sharif Tabebordbar and colleagues at the Broad Institute of MIT and Harvard while he was a supervisor, research scientist in the lab of Pardis Sabeti.

Technologies related to Tabebordbar’s work are licensed to KateTx. Internally, the company is also developing next-generation MyoAAV capsids with further targeting enhancements.

MyoAAV capsids target skeletal and cardiac muscle with dramatically higher efficiency across species compared with naturally occurring adeno-associated virus (AAV) capsids including AAV8, AAV9 and AAVrh74. These breakthroughs have the potential to improve efficacy and safety of gene therapy and enable the pursuit of a broader set of targets that are otherwise difficult to treat with current technologies.

“My father lives with FSHD, so I saw first hand the consequences of this devastating disease on patients and families. It is the reason I entered this field in the first place,” Tabebordbar said. 

“I am beyond excited that KateTx’s unique technologies are being used to develop first- and best-in-class gene therapies for patients living with serious muscle and heart diseases.”

KateTx’s cargo platform includes both internally generated proprietary capabilities and technologies licensed from the University of Florida that were developed in the laboratory of KateTx scientific co-founder Eric Wang. The overarching goal of the cargo platform is to ensure the company’s therapies are produced only in tissues of interest and not elsewhere in the body.

Near-term focus on progressing to the clinic

Beyond capsid and cargo platform efforts, KateTx has built a team with gene therapy discovery, development, manufacturing and disease area expertise. KateTx’s current focus is identifying and advancing clinical candidates for DM1 and FSHD, as well as for other genetic muscle and heart diseases.

The funding was co-led by founding investor Westlake Village BioPartners and Versant Ventures, with participation from Osage University Partners and UF Innovate | Ventures.

Kate Therapeutics is headquartered in San Diego, a hub attracting numerous biotech companies, research institutions, and professionals in the field.