AGTC Launches XLRP Gene Therapy Clinical Trial at Five Sites in U.S.
Applied Genetic Technologies Corporation (AGTC) is now recruiting for its Phase 1/2 gene therapy clinical trial for males with X-linked retinitis pigmentosa (XLRP) caused by mutations in the gene RPGR. Approximately 15 patients will be enrolled in the study, which is primarily evaluating safety. Three doses of the gene therapy will be tested. The trial is taking place at five sites in the U.S.
“We are very pleased for this trial to begin enrolling patients,” says Stephen Rose, PhD, chief research officer, Foundation Fighting Blindness. “XLRP is a devastating retinal disease affecting about 15,000 people in the U.S. AGTC’s potential treatment provides real hope to those who are in desperate need of a vision-saving therapy.”
XLRP causes progressive and significant vision loss — namely night blindness and constriction of vision — in males. Usually diagnosed during childhood, XLRP often leads to legal blindness by age 45. While females are usually unaffected carriers of XLRP, they can have vision loss, as well
“We are deeply committed to advancing gene therapy to improve the lives of people with rare inherited retinal disorders that have no available treatments,” says Sue Washer, president and CEO of AGTC. “The initiation of the XLRP clinical trial brings us one step closer to bringing a potential treatment to affected individuals with the hope for restoring their vision.”
Three genes when mutated can cause XLRP. About 70 percent of cases are caused by mutations in the gene RPGR. AGTC’s emerging therapy is designed to help patients with any mutation in RPGR.
The Foundation Fighting Blindness funded canine studies at the University of Pennsylvania that showed XLRP (RPGR) gene therapy led to vision improvements sustained for at least 3.5 years.
AGTC’s XLRP gene therapy involves injection of healthy copies of RPGR underneath the retina. The RPGR copies are contained in a human-engineered virus — known as an adeno-associated virus or AAV — which is designed to readily penetrate retinal cells to deliver the therapeutic genetic cargo.
AGTC also has two gene therapy clinical trials underway for achromatopsia, a retinal condition which leads to vision loss and day blindness. One trial is for people with mutations in CNGA3. The other is for people with mutations in CNGB3.
The company also has a clinical trial ongoing for retinoschisis, which causes vision loss from splitting of retinal layers.