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Toward a new standard of care

Developing a best-in-class treatment for Gaucher disease 

Even with current treatments, many people living with Gaucher disease type 1 still experience debilitating symptoms. These treatments also carry lifelong burdens and represent a significant, chronic spend for the healthcare system.

Our gene therapy candidate, FLT201, is designed to not only help reduce symptoms but also stop or even reverse disease progression, potentially changing the course of the disease with a single dose.

A chronic, progressive, and life-altering condition

Gaucher disease type 1 is caused by mutations in the GBA1 gene, which impact the production of the GCase enzyme. Without enough effective GCase, normal cellular processes fail to take place, resulting in a buildup of toxic substrates called GB-1 and lyso-Gb1.

This toxic buildup impacts multiple tissues and organs, including the liver, spleen, bone, and lungs. This leads to symptoms including abdominal pain, bone pain and fractures, severe fatigue, and lung dysfunction, and can ultimately shorten lives. Gaucher disease can also take a toll on patients’ overall well-being, including increased stress, anxiety, frustration, and sadness.

A need for a new treatment

The current standard of care for Gaucher disease type 1 is enzyme replacement therapy (ERT), which involves infusing the GCase enzyme every other week for the rest of a patient’s life to help make up for the deficiency. However, the infused enzymes are often quickly eliminated from the body, so patients are left without enzyme coverage between administrations.

ERT also does not fully address all of the symptoms that come with Gaucher disease. So a lifelong treatment burden of ERT can still mean severe symptoms and a diminished quality of life.

The transformative potential of FLT201 

FLT201 uses our rationally engineered GCase enzyme, GCase85, which offers a dramatically longer half-life compared to the wild-type enzyme delivered by ERT. This means more enzyme stays in the body longer, penetrating deeper tissues to more effectively reduce toxic substrate buildup. With FLT201, the idea is to provide the body with a constant and durable supply of GCase. 

The GCase85 enzyme is delivered to liver cells via our proprietary adeno-associated virus (AAV) capsid. Our capsid is highly effective at transferring genetic material to liver cells, which allows for higher levels of expression at lower doses. The liver then acts as the body’s own manufacturing plant producing GCase85 enzyme that moves into the bloodstream and is picked up by cells throughout the body. 

In preclinical studies, FLT201 has outperformed the ERT standard, demonstrating greater residence time in disease-affected tissues and organs, penetrating deeper tissues, including bone and lung, that are poorly addressed by ERT, and achieving an overall greater reduction of the toxic lyso-Gb1 accumulation in key disease-affected tissues. 

What’s next

FLT201 is currently in a Phase 1/2 clinical study that has generated promising early data. Results to date from the ongoing study show that a single infusion of FLT201 has been well tolerated and has led to reductions in lyso-Gb1 accumulation. The data also suggest the potential for improvements in bone health, pain and fatigue, and maintenance or improvements in hemoglobin, platelets, and organ size.

Based on these data, we plan to move forward into a Phase 3 trial in 2025. 

Our published results
Ongoing clinical trials