Innovations in gene-editing technology are coming

As primary eye care providers, doctors of optometry should keep an eye on gene-editing technology, such as the CRISPR-based experimental medicine under investigation for the treatment of Leber congenital amaurosis 10 (LCA10).

On March 4, the first patient was “dosed” in the clinical trial using CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) technology. In the trial, EDIT-101, the gene-editing machinery, is delivered by subretinal injection directly to photoreceptor cells. Physicians at various eye institutes, who serve as investigators in the trial, administer the injections. For instance, that first patient was injected at Oregon Health & Science University Casey Eye Institute.

The trial, touted as the world’s first in vivo (inside the body) study of the gene-editing medicine, will be assessed for safety, tolerability and efficacy.

“Since March, we have shared the update that the first patient cleared a six-month safety check without any adverse events, and we have completed dosing of the first cohort of the study,” says Dana Robie, senior manager, corporate communications for Editas, the genome-editing company behind the trial.

“While we are not sharing any specific safety or efficacy data at this time, we are pleased that the first patient’s vision remains stable, which is good news in the adult, low-dose cohort,” Robie says.

Previously slowed by the COVID-19 pandemic, Editas is actively enrolling for a pediatric cohort (ages 3 to 17) in the trial. And it is pursuing research into other genetic ocular diseases, such as Usher Syndrome 2A (USH2A) and Autosomal Dominant Retinitis Pigmentosa 4 (RP4), Robie says.

What do these developments mean for doctors of optometry?

Not a typical shot

Subretinal injection is a complex and highly technical surgical procedure where a medication is injected under the retina, says Rich Castillo, O.D., D.O., assistant dean for surgical training and education at Northeastern State University Oklahoma College of Optometry.

“A subretinal injection is not a typical ‘shot’ delivered with your standard syringe,” Dr. Castillo says. “It’s actually a very involved intraocular/retinal surgery with very specialized equipment.”

It falls outside of what is taught in optometry schools and is beyond how state law allows doctors of optometry to practice. Still, gene-editing innovations such as CRISPR can have implications for eye care and for doctors of optometry.

“Gene-editing with CRISPR technology is yielding some amazing results, as evident with the Leber’s patients,” Dr. Castillo says. “While the technology is definitely something left to a select few retinal surgeons at the present time (unless the delivery procedure evolves), doctors of optometry may actually be the ones who make the initial diagnosis of Leber’s, they will follow patients’ progress throughout life and they will make referrals where appropriate. They may do some periodic diagnostic testing, may provide visual aids and optical devices to maximize potential vision, and co-manage with other professionals.

“Many inherited diseases unfortunately have no therapy,” he adds. “And the diseases may span the spectrum of severity from color-blindness to more visually debilitating conditions such as Leber’s and retinitis pigmentosa. Because doctors of optometry deal with all these conditions from the standpoint of the primary eye care provider, they need to stay current with developments in technology and therapeutics.”

Being prepared: Optometry’s role

Doctors of optometry should be prepared for gene-editing innovations such as CRISPR and other new technology and consider how the care they provide fits with these developments, as they continue to meet the needs of patients, says Annabelle Storch, O.D., chair of the AOA New Technologies Committee.

“Gene editing will definitely transform at least one area of the profession and truly this may only be the beginning,” Dr. Storch says. “Looking at the focus of this research, there potentially will be another option someday for our patients with inherited ocular diseases. Currently, we really can only help patients prepare for and adapt to their new normal by prescribing tools and connecting them with services to help them continue to function in their worlds.

“With the possibility of the gene-editing treatments, the profession would have a whole new message and plan for these patients,” she says. “This technology represents an opportunity for doctors of optometry to change these patients' lives in extremely positive ways.”

Doctors of optometry have a professional obligation to stay current with the standard of care and with evidence-based treatment regimens in order to keep patients informed of options appropriate for their care.

Those obligations are spelled out in the AOA’s Optometric Oath, its Standards of Professional Conduct and its Code of Ethics.

“It is important that all doctors of optometry are aware of these technological advancements, so that they can best serve their patients,” Dr. Storch says. “Working in the health care realm, we have committed to staying u -to date on the profession, including treatments for the various ocular conditions we are charged with monitoring and treating.

“Furthermore, looking even further into the future, who knows if the technology could be applied in other areas that may not typically be considered inherited,” she says. “It is truly an exciting development and one that reflects our world's drive to continually understand more.”

Dr. Storch encourages doctors to share with the New Technologies Committee information on any new or upcoming technology.