Trial failures a setback to stem cell therapies

Two significant clinical trials involving novel stem cell therapies have yielded negative results, dealing a blow to research in to stem cell treatments.

The first trial involved embryonic stem cell company Geron and its spinal cord injury treatment, GRNOPC1. Last month it announced human trials were to be delayed after a small number of rats and mice in animal trials developed microscopic spinal cysts.

The US Food and Drug Administration issued a halt to the trials until more animal research could be conducted.

Another stem cell copmany, US-based Osiris Therapeutics, announced on September 8 that its stem cell treatment, Prochymal, was found to be no more effective than placebo in a late-stage trial.

Both trials were aiming to treat graft-versus-host disease (GvHD) which is a potentially fatal complication to bone barrow transplants where transplanted immune cells attack the host after transplantation.

While the failure of these trials has provided a setback to stem cell therapies, the results will still be useful in the development of new treatments, say researchers from Osiris Therapeutics.

There were also indications that Prochymal had a statistically significant effect in certain sub-groups of patients, potentially offering another avenue for future trials.