Patients & Care Partners

Ascidian is writing the next chapter in RNA medicines.

Delivering life-changing treatments for patients seeking breakthroughs.

Our Commitment

At Ascidian, we care deeply about people living with complex genetic diseases – and believe together, we can write a better future. That’s why we’ve developed a new way to treat the underlying cause of diseases by RNA exon editing.

Our initial focus is on Stargardt disease. Stargardt disease causes loss of central vision and robs people of the ability to drive, read, focus on the faces of loved ones, and more. There are no approved treatments, and as with many diseases, Stargardt disease remains out of reach of standard gene therapy approaches. Ascidian’s RNA exon editing treatment is designed to be administered just one time and address the underlying cause of Stargardt disease for a lifetime.

We are also working on a broad range of exon editing therapies across additional retinal, neurological, neuromuscular, and other conditions.

How RNA Exon Editing Works

RNA is found in all human cells. It converts genetic code – DNA – into proteins essential to the growth, repair, and functioning of the body.

Exons are parts of RNA that contain the code for making proteins. Mistakes – or mutations – anywhere in RNA may result in deficient or non-functioning proteins, causing disease.

What if we could correct mutations to slow, stop, or even reverse disease? That’s what Ascidian was formed to do.

Most gene therapy approaches focus on DNA – rewriting RNA is different.

RNA exon editing removes mutated exons and replaces them with correct exons that restore normal protein function.

Unlike standard gene editing and gene therapy, exon editing of RNA can target large genes and genes with many different mutations. It is designed to treat diseases not addressed by today’s therapies. And, because RNA exon editing does not make any DNA edits, there is less potential for unwanted, off-target effects.

Ascidian’s approach has the potential to treat patients with one dose of an RNA exon editor.

Initial Area of Focus: Stargardt Disease

Stargardt disease, the most common inherited retinal disease, affects approximately one in 10,000 people worldwide.1 It is caused by mutations in a gene called ABCA4 and is sometimes called an ABCA4 retinopathy.

In people with Stargardt disease, mutations in ABCA4 lead to deterioration of the retina and vision loss. The condition gets worse over time, eventually causing complete loss of central vision.

Stargardt disease is beyond the reach of standard gene therapy approaches because of the large size of the ABCA4 gene and huge number of mutations – and there are currently no approved treatments.

By administering one dose of our RNA exon editing therapy to a central part of the retina called the macula, Ascidian aims to stop or decrease the damage to the retina experienced by people with Stargardt disease and other ABCA4 retinopathies.

1 Cleveland Clinic, Accessed on October 9, 2023.

Learn more about RNA exon editing for Stargardt disease and beyond:

Rewriting the Story for Stargardt Disease video thumbnail

Clinical Trials

Clinical trials are essential for developing and providing innovative new medicines to patients around the world. We are grateful to the patients, care partners, physicians, nurses, and other healthcare providers who make clinical trials and the advancement of medicine possible.

Ascidian is currently initiating a clinical trial, called STELLAR, of our lead exon editing candidate ACDN-01 in adults with Stargardt disease and other ABCA4 retinopathies.

Expanded Access

Ascidian is dedicated to bringing safe and effective therapies to patients. For medicines that are not yet approved by regulatory authorities such as the U.S. Food and Drug Administration, we believe that participating in clinical trials is the best way for patients to gain access. When circumstances prevent that, sometimes patients can gain access to investigational medicines through expanded access programs.

Ascidian is currently initiating our first clinical trial, called STELLAR, of ACDN-01 in adults with Stargardt disease and other ABCA4 retinopathies, and is not able to offer expanded access at this time. As the trial progresses, we may periodically re-evaluate the need for an expanded access program.

We encourage interested patients to speak with their personal physician for more information on eligibility criteria for the STELLAR study.

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