(Reuters) - Biotechnology company ReNeuron Group Plc said its experimental stem cell therapy helped some patients improve motor functions in their arms in a mid-stage study after being disabled by stroke.

Shares of the company jumped 22 percent to 3.45 pence per share in morning trade on Monday on the London Stock Exchange.

ReNueron's trial adds to a small but growing number of studies being conducted by a few publicly listed companies around the world that are testing stem cell therapies in various indications.

Stem cell therapy development has been stalled in the past by stricter regulations in United States, and concerns over side effects in testing a field that experts believe is still in its nascent stages.


U.S. stem cell therapy developer Asterias Biotherapeutics Inc said in November that an early study of its treatment for complete spinal cord injury hit its efficacy target within three months.

Fellow U.S. stem-cell therapy developer StemCells Inc merged with Israeli company Microbot Medical Ltd in August, a week after it scrapped a mid-stage study on its treatment for spinal cord injury.

ReNeuron said that 15 out of 21 patients that were treated with the company's CTX cell therapy showed statistically significant improvement on various scales in the study.

The company said that the data was encouraging despite the study failing to meet its main goal, as some of the responses to the treatment came after the study period of three months.

Stifel analysts raised their price target on ReNeuron's stock to 15 pence from 11 pence after the statement.

The British biotech firm had set the main goal of the mid-stage study as a two-point improvement in the motor function at three months after treatment, in two patients out of the 21 who have suffered a stroke and participated in the study.

ReNeuron said on Monday that three out of the 21 patients achieved improvement in their motor function at three, six or twelve months after treatment.


The company plans on testing the stem cell treatment in a larger study.

ReNeuron had said in August that based on the results of the mid-stage study, it would apply to various health regulators to start a phase 2/3 study in the first quarter of 2017.

The company is also testing its stem cells in early stage studies to treat patients with Critical Limb Ischaemia and a kind of vision problem called Retinitis Pigmentosa.

(Reporting by Vidya L Nathan in Bengaluru; Editing by Amrutha Gayathri)