2021 ARVO Presentation OpRegen Data Overview
At ARVO 2021, additional data were presented on 24 patients enrolled in the study, including all 12 patients treated in Cohort 4, which have better baseline vision and smaller areas of GA than earlier cohorts. Updated results presented at ARVO 2021 included a minimum of 4.5 months of follow-up in all 24 patients treated with OpRegen. Nine of twenty-four patients were treated with the “thaw and inject” formulation of OpRegen, two via a standard pars plana vitrectomy (PPV) and seven utilizing the Orbit™ Subretinal Delivery System (Orbit SDS).
Overall, 10/12 (83%) 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 4.5 months to approximately 3 years post-transplant. Improvements in best corrected visual acuity (BCVA) for Cohort 4 patients reached up to +19 letters on the Early Treatment Diabetic Retinopathy Study (ETDRS) chart. In contrast, 10/12 (83%) of the patients’ untreated eyes were below pre-treatment baseline values at the same time points. Among the newly reported data, three (50%) of the more recently treated Cohort 4 patients 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 experienced a gain of 2 letters from their baseline values. One Cohort 4 patient measured 7 letters below baseline. Previously reported structural improvements in the retina, decreases in drusen density, and a trend toward slower GA progression in treated compared to untreated eyes continued. Overall, OpRegen has been well tolerated with no unexpected adverse events or serious adverse events, and evidence of durable engraftment of OpRegen RPE cells have extended to more than 5 years in earliest treated patients, supporting the potential for OpRegen to be a one-time treatment.
As part of an ongoing effort to administer the minimally effective dose and duration of immunosuppressive therapy, immunosuppression was utilized only during the perioperative period of approximately 3 months in Cohort 4 patients. One patient received a modified immunosuppressive regimen at baseline, which included no tacrolimus and only mycophenolate mofetil. One patient was diagnosed with COVID-19 shortly after treatment for whom all immunosuppression was halted and reinstated once the patient was asymptomatic. Both patients showed no signs of acute or delayed inflammation or rejection of OpRegen cells with 4.5 months of post-transplant follow up. Other than the reduced regimens described above, immunosuppressants have been discontinued as scheduled, typically within 90 days post-operatively, and no cases of acute or delayed rejection or inflammation due to OpRegen have been reported in any patients treated with OpRegen.
About the Phase 1/2a Clinical Study
OpRegen is currently being evaluated in a Phase 1/2a open-label, dose escalation safety and efficacy study of a single injection of human retinal pigment epithelium cells derived from an established pluripotent cell line and transplanted subretinally in patients with advanced dry AMD with GA. The study enrolled 24 patients into 4 cohorts. The first 3 cohorts enrolled only legally blind patients with BCVA of 20/200 or worse. The fourth cohort enrolled 12 better vision patients (vision from 20/65 to 20/250 with smaller areas of GA). Cohort 4 also included patients treated with a new “thaw-and-inject” formulation of OpRegen, which can be shipped directly to sites and used immediately upon thawing, removing the complications and logistics of having to use a dose preparation facility. The primary objective of the study is to evaluate the safety and tolerability of OpRegen as assessed by the incidence and frequency of treatment emergent adverse events. Secondary objectives are to evaluate the preliminary efficacy of OpRegen treatment by assessing the changes in ophthalmological parameters measured by various methods of primary clinical relevance. Additional objectives include the evaluation of the safety of delivery of OpRegen using the Orbit SDS. OpRegen is a registered trademark of Cell Cure Neurosciences Ltd., a majority-owned subsidiary of Lineage Cell Therapeutics, Inc. The Orbit subretinal delivery system is used under agreement with Gyroscope Therapeutics Limited. Orbit and Orbit SDS are trademarks of Gyroscope Therapeutics Limited.