Hartford, CT — A scientific breakthrough first uncovered in 1997 may soon reshape medicine.
A muscle-boosting drug, developed by Scholar Rock, is now awaiting U.S. Food and Drug Administration (FDA) approval after phase 3 trials showed strong results for spinal muscular atrophy (SMA), a rare and debilitating condition.
Dr. Se-Jin Lee, a researcher at UConn Health and The Jackson Laboratory, discovered myostatin, a protein that limits muscle growth. His work ignited a global push to suppress it.
“I could not be more excited to see this effort now on the doorstep of finally reaching fruition,” said Lee, who also consults for Biohaven.
Pharmaceutical companies have long pursued myostatin blockers, but early trials failed to deliver. That is changing.
Three firms—Scholar Rock, Biohaven, and Roche—tested the drugs in patients with SMA, and now, Scholar Rock is seeking approval for a treatment based on Lee’s discovery.
The excitement does not stop with SMA. Researchers are now racing to use myostatin blockers in the fight against obesity.
Lee’s past studies proved that animals lacking myostatin not only gained muscle but also shed fat.
“Many major pharmaceutical companies as well as biotech companies are developing drugs capable of blocking this signaling pathway, as these drugs have the potential to simultaneously increase muscle mass and reduce body fat,” he said.
The timing could not be better.
GLP-1 medications, used for weight loss, have exploded in popularity, but they come with a major flaw—up to 40% of the lost weight comes from muscle, not fat.
When people stop taking them, they gain fat back instead of muscle. Myostatin inhibitors could solve this problem.
Lee and his wife, Dr. Emily Germain-Lee, a pediatric endocrinologist at UConn School of Medicine and Connecticut Children’s, are tackling this issue.
“The challenge of the obesity epidemic is widespread and one that even pediatricians face constantly,” said Germain-Lee. “Effective treatments having the least detrimental impact on the musculoskeletal system are crucial.”
Their research has already gone beyond the lab. In 2019, they launched mice into space to test whether blocking myostatin could prevent muscle loss in zero gravity.
It did. Now, they are taking those findings back to Earth to develop therapies that help people preserve muscle while losing fat.
This research could rewrite how weight loss treatments work. If combined with GLP-1 drugs, myostatin inhibitors might allow lower doses, reducing side effects while protecting muscle mass.
The outcome? A leaner body with stronger muscles.
Germain-Lee, who heads the Scientific Center for Rare Disease at Connecticut Children’s Research Institute, sees a future where these treatments change lives.
“In addition to helping to tackle the global problem of obesity, the potential for seeing infants and children with SMA having their lives transformed by myostatin inhibitors is truly amazing.”
