A drug commonly used to treat breast cancer might be able to help people living with hereditary hemorrhagic telangiectasia (HHT) – a rare genetic bleeding condition that causes enlargements and tangles of veins and arteries, as well as other malformations of the blood vessels – according to new research from The Feinstein Institutes for Medical Research. The study, which published in Nature Cardiovascular Research, also shows that HHT could cause certain cells in the endothelium of the blood vessels to multiply via a cancer-like mechanism of abnormal cell growth.

Philippe Marambaud, PhD, professor in the Institute of Molecular Medicine at the Feinstein Institutes, led the research that shows a specific process controlled by a protein called CDK6 is making endothelial cells multiply abnormally, directly linking to the blood vessel concerns seen in HHT. Researchers used drugs Palbociclib and Ribociclib, which are known to block the CDK6 protein in multiplying cancer cells and found that it stopped the abnormal cell growth in animal models with HHT who were not following normal growth patterns in their blood vessels.

“Currently, there is no treatment for HHT, a highly debilitating disease that affects more than 1.4 million people worldwide, and little is known about what happens at the molecular level,” said Dr. Marambaud. “However, these findings are a step towards better understanding the cause of HHT and how commonly used drugs could help patients living with it.”

Results from the study suggest that by targeting CDK6 with these drugs, doctors might be able to control the excessive cell growth in blood vessels seen in HHT – which could occur in the brain, lungs, digestive system, skin and other organs.

“Repurposing already approved medications that are proven to be safe and effective for one disease presents an opportunity to develop new therapies needed for vascular disease,” said Kevin J. Tracey, MD, president and CEO of the Feinstein Institutes and Karches Family Distinguished Chair in Medical Research. “Dr. Marambaud’s research is a step forward furthering our understanding of HHT and potential therapies.”

This research comes from a $3.6 million grant Dr. Marambaud received in 2018 from the National Institute of Health (NIH) to study repurposing of FDA-approved drugs to treat HHT.