On December 6, 2021, biotechnology company Longeveron Inc. (“Longeveron”) announced that its investigational therapeutic candidate Lomecel-B earned Orphan Drug designation from the FDA. The therapy is designed to treat patients with hypoplastic left heart syndrome (HLHS), a rare congenital birth defect affecting the heart. Prior to this, Lomecel-B also earned Rare Pediatric Disease designation.

Lomecel-B

So what exactly is Lomecel-B? According to Longeveron, Lomecel-B is:

made from special living cells called Medicinal Signaling Cells, or MSCs that are isolated from fresh bone marrow tissue that has been donated by adult donors aged 18 to 45. It is becoming increasingly clear that the therapeutic effects of allogeneic MSCs occurs through secretion of bioactive molecules and direct cell-to-cell contact at the site of inflamed and damaged tissue.

The treatment is delivered directly to the heart tissue via injection. Longeveron believes that Lomecel-B helps induce positive pathways, release exosomes, reduce inflammation, regenerate cells, and form nanotube bridges to allow cellular exchange.

Within a Phase 1 clinical trial, researchers found that Lomecel-B was relatively safe and well-tolerated when administered during infants’ second heart surgeries. There were no major adverse cardiac reactions or infections related to treatment. Additionally, all of the 10 trial participants were alive, healthy, and had not needed a transplant within two to 3.5 years following treatment. Currently, a Phase 2 trial is enrolling to further evaluate the therapy.

Orphan Drug designation is granted to drugs or biologics intended to treat, diagnose, or prevent rare diseases. In this case, these are defined as conditions affecting under 200,000 Americans. Longeveron also receives a variety of benefits related to this designation, including fee waivers, tax credits, increased regulatory assistance, and 7 years market exclusivity upon Lomecel-B approval.

Hypoplastic Left Heart Syndrome (HLHS)

An estimated 1,000 babies in America are born with hypoplastic left heart syndrome (HLHS) every year. This rare defect occurs when the baby’s heart is developing. As development occurs, the left side of the heart fails to form correctly. Ultimately, this prevents the heart from effectively pumping blood. Doctors are not sure of the exact cause of HLHS. However, those with a family history of HLHS are more likely to have another child with HLHS. Surgery is required soon after birth. This is because, if the natural connections between the left and right sides of the heart close, it can be life-threatening. Symptoms of HLHS include:

• Poor feeding
• A weak pulse
• Cyanosis (a gray/blue color to the skin, lips, or nails)
• Cold hands and feet
• Rapid and difficult breathing
• Sweaty or clammy skin
• Lethargy
• Difficulty feeding