Healing the heart: Moderna co-founder, researchers near 'Holy Grail' for heart regeneration

Healing a broken heart has taken on new meaning—researchers led by Moderna's co-founder have a new approach that may repair heart function after damage, closing in on the long-awaited “Holy Grail” for patients awaiting heart transplant.

Many cardiovascular diseases can kill off heart muscle cells and blood vessels. While some animals can repair lost tissue after such damage, the human body cannot, with scar tissue instead forming and causing further deterioration.

In one study, researchers investigated the use of an enriched pool of human pluripotent stem cell derived ventricular progenitors (HVPs) to restore heart function, according to findings published May 12 in Nature Cell Biology. The scientists discovered that HVPs can detect damaged areas of the heart, migrate to the injury site, and mature into working heart cells.

“For 50+ years, heart regeneration has been the ‘Holy Grail’ for scientists, physicians and patients waiting for a heart transplant,” the study's author Kenneth Chien, M.D., Ph.D., who also co-founded mRNA giant Moderna, wrote on LinkedIn. Chien is a professor of cardiovascular research at Sweden's Karolinska Institute, which contributed to the international research team that also included AstraZeneca and biotech startup Procella Therapeutics. 

The team brought the treatment to damaged pig hearts—which are similar physiologically to human hearts—and found that damage can be reliably repaired in large animals without serious side effects.

“The treatment successfully demonstrated the formation of new cardiac tissue and importantly, improved cardiac function and reduced scar tissue,” Regina Fritsche-Danielson, Ph.D., head of research and early development at AstraZeneca, said in a May 12 news release.

The scientists plan to translate the findings into human treatment, though that requires developing a hypoimmunogenic line of HVPs. Further research will be conducted within two years, with the aim of launching clinical studies that assess the HVPs’ therapeutic use.


Previous experimental approaches for restoring heart tissue include use of heart cells grown from stem cells, though frequent side effects such as irregular heartbeats and fatal arrhythmia have been reported.

Other recent scientific endeavors aiming to treat or repair heart damage include modifying mRNA to instruct heart cells to repair themselves; combining mRNA tech and CAR-T therapy; and transiently returning adult cardiomyocytes to a fetal-like state by selectively expressing four genes essential for cell renewal.

AstraZeneca and Moderna have also partnered to develop new therapeutics for heart failure, and are currently plugging away at a potential mRNA treatment.