For Sharif Tabebordbar, the search for better treatments for genetic muscle diseases is deeply personal.
As a teenager, he watched his father develop a rare inherited muscle disorder. Over time, the disease progressed until his father could no longer walk.
That experience inspired Tabebordbar to pursue a career in gene therapy.
In an interview with the Broad Institute, he described how seeing the disease affect his family shaped his determination to help develop better treatments for patients.
Today, that work has led to a promising new gene therapy approach that could make treatments for muscle disorders safer and more effective.
A Personal Mission to Treat Muscle Disease
Many genetic muscle diseases result from mutations in a single gene.
Gene therapy aims to address those disorders by delivering a healthy copy of the affected gene into muscle cells.
Researchers often use adeno-associated viruses, or AAVs, to carry the corrective gene into the body.
These viral vectors have shown promise in several muscle diseases. However, they present important challenges.
To reach muscles throughout the body, researchers often need very high doses of the viral therapy.
Large doses can increase the amount of virus that accumulates in other organs, especially the liver. In some cases, patients have experienced serious side effects.
Researchers have spent years searching for safer delivery systems.
Engineering a Better Gene Delivery System
In a study published in Cell, Tabebordbar and colleagues at MIT and Harvard developed a new viral vector designed specifically for muscle tissue.
The team started with an existing AAV called AAV9.
They then modified its outer shell, known as the capsid.
The capsid plays a critical role because it helps the virus attach to and enter cells.
The researchers engineered a new version called MyoAAV.
Laboratory studies showed that MyoAAV delivered genes into muscle cells far more efficiently than previous AAV systems.
The new vector demonstrated a stronger ability to target muscle tissue while reducing delivery to the liver.
That combination could improve effectiveness and reduce the risk of side effects.
Promising Results for Muscle Diseases
The results were striking.
The researchers found that MyoAAV reached muscle tissues roughly 10 times more efficiently than conventional AAV vectors.
Because the vector worked so effectively, researchers achieved strong results using much lower doses.
In some cases, MyoAAV performed well at doses up to 250 times lower than those used previously.
Lower doses could improve safety while reducing the burden of treatment.
The team tested the vector in animal models of several severe muscle disorders, including:
In both cases, the approach produced encouraging results.
Looking Ahead
The researchers believe MyoAAV may have broad applications across many muscle diseases.
Because the vector performed well across different disease models, ages, and animal species, the team sees significant potential for future development.
Co-senior author Dr. Amy Wagers said the findings show the platform’s versatility and robustness.
The results suggest that researchers may be able to use the technology in a wide range of muscle-targeted gene therapies.
As with all early-stage research, additional studies will be necessary before moving toward widespread clinical use.
Researchers must confirm safety, effectiveness, and long-term outcomes in future studies.
Even so, the work represents an important advance in one of the biggest challenges facing gene therapy: safely delivering treatments to the tissues that need them most.
For patients with inherited muscle diseases, that progress could eventually open the door to more effective and safer therapies.
Will this be for cerebral palsy patients also? CP is all about tight muscles.
Possibly in time it could be used to help people with CP