(Sharecast News) - Cell-based therapeutics developer ReNeuron Group updated the market on progress with its ongoing phase 1 and 2 clinical trial in the US of its 'hRPC' cell therapy candidate in the blindness-causing disease retinitis pigmentosa (RP) on Thursday, confirming that the positive efficacy seen and previously announced had, to date, been sustained in the first patient cohort in the phase 2 part of the study. The AIM-traded company had reported in February that all three of the first cohort of subjects in the study had reported a "rapid and significant" improvement in vision, on average equivalent to reading an additional three lines of five letters on the ETDRS eye chart - the standardised eye chart used in clinical trials to measure visual acuity.Last month, it announced that dosing of the second cohort of three phase 2 subjects had begun.That next dose cohort comprised patients who had a greater baseline level of visual acuity than those treated in the study thus far.Further read-outs from the patients treated in the study would be presented at the sixth annual Retinal Cell and Gene Therapy Innovation Summit, taking place in Vancouver, Canada on 26 April.ReNeuron said it would make a further announcement later in April, when those further read-outs from the study were known.The company said its RP clinical programme benefited from 'Orphan Drug Designation' in both Europe and the US, as well as 'Fast Track' designation from the FDA. "We remain greatly encouraged by the continued positive efficacy we are seeing in the ongoing phase 1 and 2 study with our hRPC cell therapy candidate for retinitis pigmentosa," said chief executive officer Olav Hellebø."We look forward to providing a further update on progress with the study at the time of the Innovation Summit in Vancouver later this month."