Beacon Therapeutics may have found a guiding light in a disease area where other companies have stumbled with its laruparetigene zovaparvovec (laru-zova), a gene therapy that proved early improvements in patients with X-linked retinitis pigmentosa (XLRP).
Data from Beacon’s interim six-month safety and efficacy results from a phase 2, announced May 6, pointed to improvements across “several key measures” of visual function, the private company said, including in low luminance visual acuity and eye sensitivity. The study is being conducted in the untreated eye of patients who have already received adeno-associated-virus-based gene therapy for XLRP in one eye.
XLRP is an inherited retinal disease hallmarked by progressive vision loss that starts in childhood and often leads to blindness by middle age, affecting 1 in 25,000 males across the U.S., Europe and Australia, according to Beacon. There are no available treatment options targeting the disease.
Laru-zona is what Beacon describes as a “potential best-in-class” candidate that’s meant to restore the natural function of both rods and cones in XLRP-patients’ eyes by sending in a functional copy of the retinitis pigmentosa GTPase regulator (RPGR) gene. Last July, Beacon raised a $170 million series B to advance the asset and explained that it would combine the results from the phase 2 study and a phase 1 /2 trial to support applications for approval in the U.S. and Europe.
The company has so far built a “compelling body” of safety and efficacy data on the drug over five years through three clinical studies, CEO Lance Baldo, M.D., said.
The latest update “continues to demonstrate laru-zova's potential to enhance vision in patients with XLRP,” Baldo said, adding that the company looks forward to “continuing the advancement of this exciting novel treatment option.”
This phase 2 test, known as Dawn, is only sharing an interim picture as an open-label, non-randomized trial focusing in on safety and is not yet determining full data on efficacy. The phase 2/3 Vista study, currently recruiting, should give a stronger image of how this therapy works. It's set up as randomized, controlled study evaluating the efficacy, safety and tolerability of laru-zova in two study groups compared to an untreated control group.
The Dawn data, however, are an early positive for a disease area that has stumped several drugmakers, most recently Johnson & Johnson.
J&J reported on May 2 that its own investigational gene therapy, botaretigene sparoparvovec (bota-vec) didn’t meet its primary endpoint of helping XLRP patients improve their ability to visually navigate through a virtual maze in the phase 3 Lumeos trial. Although the study did make a difference in several secondary endpoints including visual acuity, J&J did not claim those as statistically significant. Still, a spokesperson said that the company is “working to understand the totality of the data.”
4DMT, meanwhile, scrapped its XLRP program earlier this year. The gene therapy was being evaluated in a phase 1/ 2 trial that was expected to read out next year.