ReNeuron’s human retinal progenitor cell therapy candidate for retinitis pigmentosa has shown a mean improvement in visual acuity in a phase 1/2a clinical trial, according to a press release.
In the phase 2a segment of the study, which used a cryopreserved human retinal progenitor cell (hRPC) formulation, visual acuity improvement was 8.3 ETDRS letters in the treated eye compared with 1.6 letters in the untreated eye. After 6 months, the treatment eye saw a mean visual acuity improvement of 18.5 letters compared with 7.8 letters in the untreated eye, whereas improvement after 9 months was 12 letters compared with –1 letter in the untreated eye.
While the first three patients in the phase 2a portion experienced “rapid and profound” improvement, subsequent patients have experienced a lower rate and magnitude of improvement in visual acuity, ranging from 5 to 11 letters in the first 3 months after treatment.
Twenty-two subjects have been treated in the study, with two patients experiencing loss of vision due to the surgical procedure. No product-related serious adverse events have been reported, the release said.
“We are greatly encouraged by the latest efficacy data from the ongoing phase 1/2a clinical study of our hRPC cell therapy candidate in patients with RP,” Olav Hellebø, CEO of ReNeuron, said in the release. “It is especially gratifying to see positive data given the inherent challenge in addressing a disease as complex as RP, and we look forward to further progressing the clinical development of this promising cell therapy candidate.”