Geron Corporation (Nasdaq:GERN) provided additional comments on the recent clinical hold on its Spinal Cord Injury IND.

As biologic therapeutics advance in clinical trials, it is common practice to optimize product characteristics, improve manufacturing efficiency and scale, and to test the product in multiple disease models. As part of these ongoing efforts at Geron with respect to GRNOPC1, various animal studies were, and continue to be, performed to characterize the product's effects in vivo. In previous animal studies of GRNOPC1 using materials that passed release specifications, a very low frequency of injected animals developed microscopic cysts in the regenerating injury site. These cysts were non-proliferative, confined to the injury site, and had no adverse effects on the animals. No animals developed teratomas or any other ectopic structure. Cysts of much larger size appear in the spinal cord scar tissue of up to 50% of patients with spinal cord injury.

A just completed animal study showed a higher frequency of cysts, although their characteristics were similar to the cysts seen in previous studies: non-proliferative, confined to the injury site, smaller than the injury cavity and not associated with adverse clinical outcomes.

As part of our ongoing product improvement efforts, new candidate markers and assays for product release have been identified that are linked with cyst formation across all animal studies in which cysts were found. Importantly, a manufactured lot of GRNOPC1 that was assessed using these markers and assays showed no cysts in another recently concluded animal study in spinal cord injured rats.

We have submitted these data to the FDA and are in discussions with the agency to answer its questions and proceed with the clinical trial. We are committed to the optimization of all our hESC-based products as we improve the manufacturing process and identify improved product release criteria.

Source
Geron Corporation