Research Update

Gene Therapy Achieves Sustained Beneficial Outcomes In Treating LHON Over 3 Year Period

Leber Hereditary Optic Neuropathy (LHON) is a rare and inherited retinal condition which occurs when mitochondria; the “powerhouse of the cell” fails to produce sufficient energy to support normal cell activity. This lack of energy can lead to the degeneration and death of retinal ganglion cells (RGC’s), which are responsible for delivering visual information from the eyes to the brain so images can be formed of our surrounding environment. Vision loss due to LHON does not cause any eye pain, but it is quite an alarming experience as central vision can deteriorate quite quickly, leaving only peripheral vision.

Recent results from the long-term CLIN06 follow-up study report that individuals who received a single gene therapy injection (LUMEVOQ^®) experienced sustained beneficial outcomes with respect to both its effectiveness and safety for treating LHON over a three year period¹.

In total, 61 individuals were enrolled in CLIN06, 30 and 31 of whom came from the RESCUE and REVERSE Phase III clinical trials respectively. At two years post treatment, an average improvement in best corrected visual acuity (BCVA) of 18.8 letters was recorded in treated eyes and 17.3 letters in sham-treated eyes relative to the worst recorded BCVA (nadir) in any of the CLIN06, RESCUE and REVERSE studies, including the baseline measurement taken immediately prior to injection. Three years post injection, an average BCVA improvement of 20.5 letters and 19.4 letters were recorded for LUMEVOQ^® and sham treated eyes against nadir respectively. This evidence indicates that the improvement to visual function in people living with LHON is achieved and maintained up to three years post treatment.

According to Dr. Mark L. Moster, Neuro-Ophthalmology, Wills Eye Hospital, Professor of Neurology and Ophthalmology at Thomas Jefferson University, Philadelphia, PA, and Principal Investigator in the RESCUE, REVERSE and CLIN06 trials. “These results are far better than the natural history of LHON and provide further hope for improving the lives of our patients with this blinding disease.”

With respect to the safety, no serious adverse events were recorded among LUMEVOQ^®-treated eyes, and no discontinuations occurred due to ocular events caused by study procedure or treatment. Additionally, safety findings at three years were consistent with previous readouts, which concluded that LUMEVOQ^® is well-tolerated.

The findings from this long-term follow-up study present the potential for LUMEVOQ^® to be used as a prominent therapy for LHON because of its ability achieve beneficial visual outcomes which are sustained and well tolerated over a three year period by a single treatment intervention.

References:

GenSight Biologics. GenSight Biologics reports sustained efficacy and safety among LHON patients three years after LUMEVOQ® treatment. Available at https://www.gensight-biologics.com/2020/07/06/gensight-biologics-reports-sustained-efficacy-and-safety-among-lhon-patients-three-years-after-lumevoq-treatment/. Accessed July 2020.