A highly anticipated and contentious clinical investigation, aimed at rejuvenating senescent ocular cells and restoring their youthful vitality, has officially commenced.
This week, the United States-based biotechnology firm Life Biosciences, Inc. disclosed the administration of its inaugural dose to a participant in an experimental therapeutic regimen intended to reverse age-associated visual impairment.
The audacious premise involves arresting the aging process by stimulating three specific genes within retinal ganglion cells, which serve as the neural conduits between the brain and the eyes.
These neural pathways possess no innate capacity for regeneration. Their compromise due to pathologies such as glaucoma can precipitate sudden, asymptomatic visual deterioration culminating in permanent sight loss.
An investigational agent, designated ER-100, is currently undergoing human trials to address this irreversible degeneration.
However, the ethical considerations surrounding its implementation are a subject of ongoing discourse.
The objective is to achieve preservation or even restoration of vision in individuals experiencing uniauricular or binauricular sight deficit, through a solitary gene therapy injection coupled with a regimen of antibiotics over several weeks.
This represents one of the most eagerly awaited clinical investigations of the year, with some prognosticating it as a landmark event for the gerontology research domain.
Conversely, a segment of the scientific community contends that it entails “extraordinary levels of risk” and harbors reservations regarding its potential efficacy.
“This marks a significant milestone for Life Bio and the broader field of aging biology,” opined David Sinclair, co-founder of Life Bio and a geneticist affiliated with Harvard University, who has dedicated several years to the study of ER-100.
“Our research indicates that aging is largely instigated by the diminution of epigenetic information, rather than irreparable damage. This clinical investigation provides the inaugural opportunity to ascertain whether the reinstatement of such information can alleviate human ailments.”
Sinclair and his collaborators at Harvard University have been engaged in the development of ER-100 for an extended period.
In 2020, their findings demonstrated the capacity to partially reprogram aged cells in murine models using ER-100, thereby inducing a more youthful cellular phenotype.
The intellectual property pertaining to this technology was subsequently licensed by the Harvard researchers to Life Bio, an enterprise co-founded by Sinclair, which has undertaken extensive preclinical evaluations since its inception.
On January 15th of the current year, the United States Food and Drug Administration (FDA) granted approval for this novel therapeutic modality to proceed to its initial human clinical trial.
The therapeutic strategy is engineered to ‘reset’ the epigenetic modifications that accumulate on DNA throughout the lifespan.
Should aged cells within the human organism be safely reverted to a more youthful state, the potential applications are virtually limitless.
Nevertheless, it is prudent to exercise restraint and await empirical findings before drawing definitive conclusions. This initial study is a small-scale investigation prioritizing safety, involving a maximum of 18 individuals. While the potential benefits are considerable, so too are the inherent risks.
Preliminary investigations conducted on non-human primates suggest that ER-100 holds promise for restoring the functionality of compromised cells. However, manipulation of gene expression is fraught with potential complications, encompassing both known and unforeseen hazards, such as oncogenesis.
“A significant challenge lies in the fact that ER-100, even under optimal reprogramming conditions (though these are not definitively established for the human eye), will not reduce intraocular pressure in glaucoma,” articulated stem cell biologist Paul Knoepfler of the University of California, Davis, earlier this year on his platform, The Niche.
“Therefore, any rejuvenation achieved may prove transient.”
The mechanism of ER-100 involves the introduction of a viral vector—rendered avirulent and incapable of causing infection—into the subject’s system.
This viral vehicle is instrumental in delivering genetic directives to the retinal ganglion cells. These genetic blueprints encode for three proteins that contribute to the restoration of cellular youthfulness and functionality, at least according to certain metrics.
The expression of these genes is regulated by a genetic switch that is activated only upon the administration of a specific antibiotic to the participants.
Discontinuation of the antibiotic intake results in the deactivation of these genes, thereby affording a degree of therapeutic control.
“ER-100 does not induce alterations in the participant’s endogenous genes,” asserts the clinical trial documentation.
The inaugural human trial involving ER-100 will commence with the treatment of 12 participants, individually, afflicted with a specific classification of glaucoma known as open-angle glaucoma (OAG).
Subsequently, the research team will incorporate up to an additional 6 participants diagnosed with optic nerve damage termed nonarteritic anterior ischemic optic neuropathy (NAION).
Participants will be monitored for a minimum of five years; however, the dosage administered may not be uniform across all subjects. Scientific personnel will incrementally adjust the therapeutic quantity based on patients’ responses.
While this initial trial’s primary objective is to ascertain safety parameters, it will also yield preliminary findings concerning the treatment’s impact on visual acuity.
It remains indeterminate whether a regimen of this therapy can genuinely ‘reverse aging’ within retinal ganglion cells. Indeed, scientific consensus is lacking regarding the precise definition of such a phenomenon.
Currently, biological aging is quantified using a multitude of distinct ‘clocks,’ each seemingly influencing cellular health, functionality, and lifespan.
However, the relative significance of these various clocks is a point of contention. Furthermore, the necessity of recalibrating all of them to substantiate claims of aging ‘reversal’ is also debated.
Sinclair has previously faced scrutiny from his peers. His overarching theory of aging, which underpins the development of this treatment, will now undergo rigorous examination within the clinical trial.
Critics assert that Sinclair tends to exaggerate the purported benefits of experimental longevity interventions that have not undergone adequate validation for safety or efficacy.
While the inaugural ER-100 clinical trial may provide some initial insights, Knoepfler remains unconvinced of the therapy’s readiness for human application.
“From a stem cell biology perspective, I find all forms of cellular reprogramming, particularly when applied to disease treatment, profoundly intriguing,” communicated Knoepfler on The Niche in February.
“However, it is imperative to maintain a realistic outlook. Numerous complications can arise.”
