September 25, 2020

The Niche

Knoepfler lab stem cell blog

The latest scoop on ACT and Geron

Advanced Cell Technology  (ACT) announced today that it has treated two patients in its clinical trials: one for Stargardt’s Macular Dystrophy (see official trial page for a lot more info) and one for Dry Age-Related Macular Degeneration (see official trial page here for a lot more info).

The patients underwent the treatment at UCLA and each reportedly received about 50,000 cells as a transplant into the eye. The cells being used are retinal pigmented epithelial cells produced from human embryonic stem cells (hESC).

The primary purpose of this stage of the trials is to determine safety. It is unclear if that dose of cells would have the potential to produce a positive outcome in terms of demonstrating efficacy.

The plan is to enroll 11 more patients in each of ACT’s trials for a total of 12 each. Three patients each will receive increasing doses of cells up to 200,000.

In both cases, one potential limiting factor in the secondary outcome measures (goal) of  looking for evidence of efficacy, is that the enrollment guidelines for the trials dictate that the patients have very advanced disease, which is inherently going to be far more difficult to treat. Thus, being realistic, the stem cell community should be hoping for a strong safety profile and not be counting on finding out much about efficacy at this stage.

Geron, another company with a hESC-based clinical trial (read everything you want to know about the trial here) under way has also treated two patients. While not surprisingly there is no news on efficacy, reportedly neither patient has suffered an adverse outcome.

I hope Geron and ACT succeed, and that more trials start, but patience is essential at this stage.