Lineage Cell Therapeutics announced new positive interim results from its ongoing, 24-patient phase 1/2a clinical study of its lead product candidate, OpRegen. OpRegen is an investigational cell therapy consisting of allogeneic retinal pigment epithelium (RPE) cells administered to the subretinal space for the treatment of dry age-related macular degeneration (AMD) with geographic atrophy (GA). Additional interim data were collected on all 24 patients enrolled in the study, including the 12 patients treated in Cohort 4, which feature less advanced disease, better baseline visual acuity, and smaller areas of GA.
Overall, 9/12 (75%) of the Cohort 4 patients’ treated eyes were at or above baseline visual acuity at their last assessment, based on per protocol scheduled visits ranging from 3 months to > 2 years post-transplant. Improvements in best corrected visual acuity (BCVA) reached up to +19 letters on an EDTRS chart. In contrast, 9/12 (75%) of the patients’ untreated eyes were below baseline entry values at the same time points. Among the newly reported data, three (50%) of the more recently treated Cohort 4 patients have exhibited marked improvements in BCVA ranging from +7 to +16 letters at their last scheduled assessments of at least 4.5 months. Two additional Cohort 4 patients remained within 2 letters of their baseline values (one each above and below). One patient measured 7 letters below baseline.
Previously reported structural improvements in the retina and decreases in drusen density have continued with evidence of durable engraftment of OpRegen cells in some treated patients now extending to more than 5 years in the earliest treated patients. A trend towards slower GA progression in treated compared to fellow eyes also continued, although significant changes in GA growth over a 3-month period following treatment are not expected. Overall, OpRegen has been well tolerated with no unexpected adverse events or serious adverse events.
“Data collected from the six additional Cohort 4 patients which we treated last fall has reinforced our prior results and further supports that treatment with OpRegen may provide clinically meaningful outcomes in dry AMD patients with GA. Improvements in BCVA have become apparent within a few months after dosing, consistent with the predicted activity of an RPE cell transplant,” Brian M. Culley, Lineage CEO, said in a company news release. “If these early indications of a treatment effect are maintained or improve further, it will be another positive indicator for the potential of OpRegen to improve outcomes in this condition. We continue to monitor all patients on study and in the coming months we will be looking in particular for indications of retinal restoration, reductions in the size and growth of the areas of GA, and functional improvement in visual acuity. Further, the multi-year stability of OpRegen transplants, some in excess of 5 years without signs of rejection, is notable for the durability of our allogeneic cell therapy approach, especially as patients did not require long-term immunosuppression.”
As part of an ongoing effort to administer the minimally effective dose and duration of immunosuppression, reflecting the COVID pandemic and age of typical AMD patients while ensuring the survival of OpRegen cells, no immunosuppression was utilized beyond the perioperative period of up to 3 months in Cohort 4 patients. Notably, the one OpRegen patient who had received a modified immunosuppressive regimen at baseline, which included no tacrolimus and only mycophenolate mofetil, does not show any signs of acute or delayed inflammation or rejection of OpRegen cells. One other patient was diagnosed with COVID shortly after treatment with OpRegen and all immunosuppression was halted and then reinstated once the patient was asymptomatic. This second patient similarly showed no signs of acute or delayed inflammation or rejection of OpRegen cells. Other than the reduced regiments described above, immunosuppressants have been discontinued as scheduled, typically within 90 days postoperatively, and no cases of acute or delayed rejection or inflammation due to OpRegen have been reported.
Additional details regarding this data will be presented as part of a corporate update by Mr. Culley at the Benzinga Global Biotech Small Cap conference on March 24, 2021 at 11:50am Eastern Time / 8:50am Pacific Time. Mr. Culley will also be participating in a panel entitled “Coming Together to Address Unmet Medical Needs,” on March 24, 2021 at 12:50pm Eastern Time / 9:50am Pacific Time. Interested investors are encouraged to register for the event in advance: https://www.benzinga.com/events/small-cap/biotech/. The live and archived webcasts from the event will be available on the Events and Presentations section of Lineage’s website.