MARLBOROUGH, Mass. — Sumitomo Pharma America has treated the first patient in a Phase 1/2a clinical study evaluating DSP-3077, an investigational regenerative cell therapy for non-syndromic retinitis pigmentosa.
DSP-3077 is an allogeneic retinal sheet derived from induced pluripotent stem cells and administered through subretinal implantation.
The open-label, single-arm, dose-escalation study is evaluating two dose levels of DSP-3077 in adults with retinitis pigmentosa. Its primary objective is to assess safety and tolerability, while secondary objectives include evaluating engraftment, potential therapeutic response and performance of the delivery device.
The study will enroll 12 participants across three cohorts, with four patients in each cohort. The groups will be defined by visual acuity criteria and DSP-3077 dose level.
“We are encouraged by the potential that iPS cells may hold for treating degenerative, debilitating conditions like RP that currently have few therapeutic options, and this first patient treated is a notable milestone for our company,” said Tsutomu Nakagawa, Ph.D., President and Chief Executive Officer of Sumitomo Pharma America. “Being able to provide this investigational treatment to our first study participant is not only a great honor, but a very important milestone in the development of DSP-3077, one that will aid in better understanding how it and future iPSC therapies could help improve the lives of RP patients and their families.”
Retinitis pigmentosa is a group of inherited retinal disorders characterized by the progressive degeneration of photoreceptor cells, leading to worsening vision and, in many cases, eventual loss of central vision. The condition affects an estimated one in 4,000 people and currently has limited treatment options.
DSP-3077 is based on a three-dimensional retinal organoid produced using a self-organizing cell culture technique. The organoid is processed into multilayered retinal sheets containing retinal tissue structures and photoreceptor precursor cells.
The underlying technology originated from research led by Yoshiki Sasai at RIKEN in Japan and was further developed through collaborations involving Sumitomo Chemical, Sumitomo Pharma and other partners.
Sumitomo Pharma America said DSP-3077 received Orphan Drug Designation from the U.S. Food and Drug Administration for the treatment of retinitis pigmentosa in March 2026.
