US-based StemCells has finished enrolment of the first of two planned patient groups in a clinical trial of its HuCNS-SC product candidate (purified human neural stem cells) for the treatment of dry age-related macular degeneration (AMD).
In the Phase I/II trial, subjects will be enrolled into each group based on best-corrected visual acuity (BCVA) visual acuity as determined by the Electronic Early Treatment Diabetic Retinopathy Study (E-ETDRS) acuity test.
BCVA of less than or equal to 20/400 in the Study Eye will be enrolled in the first group, while subjects with BCVA of 20/320 to 20/100 will be enrolled in the second Cohort II.
The first group will include eight subjects, with four will undergoing transplant with 200,000 cells followed by the remaining four subjects who will undergo transplant with one million cells.
In the second group, eight subjects will be participating who will undergo transplant with one million cells.
Byers Eye Institute at Stanford director of ophthalmic diagnostics Dr Ted Leng performed the transplant in the last patient in this cohort.
In the trial, the HuCNS-SC cells will be administered by a single injection into the space behind the retina in the most affected eye.
Patients' vision will be assessed using both conventional and advanced state-of-the-art methods of ophthalmological assessment, while evaluations will be performed at predetermined intervals over a one-year period to assess safety and signs of visual benefit.
According to the company, patients will then be followed for an additional four years in a separate observational study.
StemCells vice-president of CNS Clinical Research Stephen Huhn said the company's goal for the study in the next quarter is to complete enrolment of the second cohort.
"The eight patients in this stage of the trial will have better visual acuity than those in the first cohort," Huhn said.
"We are expanding the trial from two sites at the beginning to ultimately a total of five sites, and with additional sites actively evaluating patients, the second cohort should be completed by mid-year.
"We also expect to announce interim follow-up data on the first cohort later this year."
After completion of enrolment in the second group, the company intends to start a controlled Phase II efficacy proof-of-concept trial by the end of 2014.
A degenerative retinal disease, AMD refers to a loss of photoreceptors (rods and cones) from the macula, the central part of the retina.
The disease usually affects adults in their 50s or early 60s and gradually progresses to destroy central vision.
An estimated ten million people in the US either have AMD or are at substantial risk for receiving the diagnosis, according to the Foundation Fighting Blindness.
Image: Picture of the fundus showing intermediate age-related macular degeneration. Photo: courtesy of Dcirovic.