Rocket Pharmaceuticals, a company that specializes in developing genetic therapies for rare childhood disorders, just got a big boost from the European Medicines Agency (EMA). They were given a Priority Medicines (PRIME) designation for their therapy for Leukocyte Adhesion Deficiency-1 (LAD-1).

CIRM is funding ($6.56 million) Rocket’s clinical trial for LAD-I, an immune disorder that leaves patients vulnerable to repeated infections that often results in death within the first two years of life. The therapy involves taking some of the child’s own blood stem cells and, in the lab, correcting the mutation that causes LAD-I, then returning those cells to the patient. Hopefully those blood stem cells then create a new, healthy blood supply and repair the immune system.

The therapy, called RP-L201, is already showing promise in the clinical trial, hence the PRIME designation. The program was set up to help speed up development and evaluation of therapies that could help patients who have limited treatment options. Getting a PRIME designation means it is considered a priority by EMA and could reach patients sooner.

In the US, Rocket has won similar recognition from the Food and Drug Administration (FDA) and has been granted Regenerative Medicine Advanced Therapy (RMAT), Rare Pediatric Disease, and Fast Track designations.

In a news release Kinnari Patel, President and Chief Operating Officer of Rocket, said the designation showed that regulators understand the urgent need to develop a therapy for patients with LAD-1. “More than half of LAD-I patients suffer with a severe variant in which mortality occurs in up to 75% of young children who don’t receive a successful bone marrow transplant by the age of two. Securing all possible accelerated designations will enable us to collaborate with both the FDA and EMA to speed the development and delivery of a potential treatment for these patients.  We look forward to sharing initial Phase 2 data from our potentially registration-enabling LAD-I trial in the second quarter of 2021.”

That trial has now completed enrolling patients (nine altogether) but their treatments are not yet complete. LAD-1 patients with severe disease have low levels of a key protein called CD18, usually less than 2%. Of the first three patients treated in this trial CD18 levels are all higher than the 4-10% threshold considered necessary for these children to survive into adulthood. Another encouraging sign is that there were no serious side effects from the therapy.

Obviously there is still a long way to go before we know if this therapy really works, but the PRIME designation – along with the similar ones in the US – are recognition that this is a very promising start.