Exicure’s Program for Friedreich’s Ataxia Not Altered by COVID-19
Since biotechnology companies were designated essential businesses by the state’s governor J.B. Pritzker, Exicure will continue its research programs despite the the “stay-at-home” order in Illinois.
The company also expects to initiate investigational new drug-enabling studies for XCUR-FXN — intended to support regulatory clearance of clinical trials — late this year.
“Exicure is carefully monitoring the developing COVID-19 crisis and we have taken active measures, both as required by government regulation and as judgement suggests, to protect the health of our employees, their families, our communities, as well as clinical trial investigators, patients, and caregivers,” David Giljohann, MD, Exicure’s CEO, said in a press release.
“While health and safety are our first priorities, we also have a strong commitment to our fundamental mission of serving patients with unmet medical needs. We are taking appropriate actions to continue our critical research and development programs and are grateful to our employees and their families for their commitment to this mission,” he said.
FA is a rare neurodegenerative disorder caused by excessive repeats of a portion of DNA — called GAA triplets (G stands for guanine and A for adenine, two of the four building blocks of DNA) — within the FXN gene. This gene contains instructions to produce frataxin, an essential protein for the normal functioning of mitochondria, the cells’ powerhouses.
This expansion of GAA triplets significantly lowers the production of frataxin, leading to mitochondrial dysfunction and impaired energy production in several organs, ultimately resulting in FA symptoms.
Antisense oligonucleotides (ASOs) are small molecules that can be designed to modify — suppress or boost — the production of a specific protein. So far, this strategy has been applied successfully to develop approved therapies for genetic neuromuscular diseases such as spinal muscular atrophy (SMA) and Duchenne muscular dystrophy.
XCUR-FXN uses the ASO approach while intending to improve treatment entry in cells. It is being developed by Exicure, in collaboration with the Friedreich’s Ataxia Research Alliance (FARA), to increase the production of frataxin.
Its design is based on Exicure’s innovative technology, called spherical nucleic acids (SNAs), in which oligonucleotides are very tightly packed around a nanoparticle core. SNAs’ sphere shape and structural properties allows them to enter cells easier and to persist longer than some other forms of ASOs, as shown in animal models.
Previous studies in rodents and monkeys showed that administration of SNAs into the spinal canal resulted in an effective distribution of SNAs to all brain regions, including those relevant in FA.
Also, the approved ASO-based therapy for SMA, Spinraza (nusinersen, marketed by Biogen), showed higher potency when changed to an SNA format in a study in rats, supporting this approach’s potential in treating central nervous system (brain and spinal cord) conditions.
Besides its program in FA, Exicure also said that, at this point, its ongoing Phase 1b/2 clinical trial (NCT03684785, now enrolling) of AST-008 in Merkel cell carcinoma and squamous cell carcinoma — as well as its current collaborations with other companies — will continue as planned.