• Posted April 4, 2024

First Treatment Found for Rare Disease That Can Lead to Amputation

There's a glimmer of hope for people afflicted by a rare artery-hardening disease than can lead to amputation.

An existing medication called etidronate appears to help slow the buildup of calcium in arteries that's a hallmark of the illness, which is called arterial calcification due to deficiency of CD73 (ACDC).

ACDC is incredibly rare, affecting less than 1 in every 1 million people; there may be only 20 people affected worldwide.

It's caused by a genetic defect and is typically diagnosed in a person's teens or 20s. Calcium builds up in arteries, most notably the legs, and walking becomes painful and difficult. It can also cause the hands to become deformed. In some cases, amputation is required.

The study was funded by the National Heart, Lung, and Blood Institute (NHLBI), part of the National Institutes of Health. Researchers there discovered the underlying genetic cause of ACDC, and then spotted etidronate as a medicine that might help.

In the new study, seven people with ACDC (about a third of all known cases worldwide) received etidronate to help ease impaired blood flow in their legs. For three years, they took the drug for 14 days every three months.

Based on CT scans, the treatment appeared to slow the buildup of calcium deposits in leg arteries, reported a team led by Elisa Ferrante, clinical program manager and staff scientist in the Translational Vascular Medicine Branch at the NHLBI.

Unfortunately, etidronate could not remove any calcium that had already collected in arteries prior to treatment, and it did not lead to any improvement in blood flow.

But blood flow did not worsen, Ferrante's team noted, and the drug appeared to have no side effects. Patients said their pain, lack of mobility and other symptoms did improve after taking the drug.

The NHLBI team said they hope the finding leads to new insights for even better drugs against ACDC.

The study was published April 3 in the journal Vascular Medicine.

More information

Find out more about ACDC at the National Human Genome Research Institute.

SOURCE: National Heart, Lung, and Blood Institute, news release, April 3, 2024