Sumitomo Pharma America Doses First Patient in Phase 1/2a Trial of iPSC-Derived Cell Therapy DSP-3077 for Retinitis Pigmentosa
核心洞察
Sumitomo Pharma America (搜索) announced the first patient has undergone subretinal implantation in its Phase 1/2a study evaluating DSP-3077 for non-syndromic retinitis pigmentosa (搜索) (RP).
DSP-3077 is an allogeneic regenerative cell therapy using retinal sheets derived from induced pluripotent stem (iPS) cells with photoreceptor precursors, manufactured via the SFEBq method.
The FDA granted Orphan Drug Designation for DSP-3077 in March 2026, qualifying it for tax credits, user fee exemptions, and up to 7 years of market exclusivity.
Sumitomo Pharma America (搜索), Inc. (SMPA) announced that the first patient has undergone subretinal implantation in its Phase 1/2a study evaluating DSP-3077 for the treatment of non-syndromic retinitis pigmentosa (搜索) (RP). The milestone marks the first clinical dosing of an investigative allogeneic regenerative cell therapy leveraging retinal sheets derived from induced pluripotent stem (iPS) cells with photoreceptor precursors.
SMPA was formed in 2005 through the consolidation of Sumitomo Pharma's seven U.S. affiliate companies, building on the 100-year history of Sumitomo Pharma Group. The company's focus spans oncology, urology, women's health, rare diseases, cell and gene therapies, and the central nervous system (CNS).
The DSP-3077 Technology Platform
DSP-3077 is an investigative regenerative cell therapy that utilizes allogeneic retinal sheets derived from induced pluripotent stem (iPS) cells containing photoreceptor precursors. iPS cells are derived from adult somatic cells and have been genetically reprogrammed to an embryonic stem (ES) cell-like state through the forced expression of genes and factors important for maintaining the defining properties of ES cells.
The technology underlying DSP-3077 is based on a self-organizing cell culture technique known as the SFEBq method, a robust differentiation method used to generate three-dimensional neural tissues and organoids from pluripotent stem cells. This approach was created by Yoshiki Sasai and his team at RIKEN (搜索) (Tokyo, Japan), and enables pluripotent stem cells to develop into organized neural structures and organoids through self-directed cellular organization.
Regulatory Status
The FDA granted Orphan Drug Designation (ODD) for DSP-3077 for the treatment of RP in March 2026. ODD is a special regulatory status granted by the FDA for certain investigational drug candidates that demonstrate promise for diagnosing, treating, or preventing "orphan" diseases—rare, serious, or life-threatening diseases or conditions (such as RP) that affect fewer than 200,000 patients in the United States.
While candidates deemed to be orphan drugs undergo the same scientific review process as any other drug seeking regulatory approval, they are also qualified to receive tax credits for qualified clinical trials, user fee exemptions, and potential 7 years of market exclusivity following approval.
Study Design and Patient Population
The Phase 1/2a, open-label, single-arm, uncontrolled dose-escalation study (NCT06891885) is evaluating two dose levels of allogeneic iPS cell-derived retinal sheets administered with a single subretinal, uniocular injection in adults with RP. Study participants will be treated in three cohorts, with each cohort defined by best-corrected visual acuity (BCVA) criteria and dose level of DSP-3077.
Cohort 1 includes participants with BCVA in the study eye between hand motion and 20 Early Treatment Diabetic Retinopathy Study (ETDRS) letter score (approximately ≤ 20/400), inclusive at screening and baseline, receiving a dose of ≥ 0.8 to < 2.4 mm². Cohort 2 uses the same BCVA criteria with a higher dose of ≥ 2.4 to < 6.4 mm². Cohort 3 includes participants with BCVA between 20 ETDRS letter score (approximately ≥ 20/400) and 35 ETDRS letter score (approximately ≤ 20/200) at screening, and between 10 ETDRS letter score (approximately ≥ 20/640 Snellen equivalent) and 35 ETDRS letter score at baseline, receiving a dose of ≥ 2.4 to < 6.4 mm². Each cohort will include four participants for a total of 12 participants.
The total study duration will be approximately 67 months from the start of screening through the end of the extension observation period in part B. After an initial 2-week period of frequent visits following surgery, visit frequency will be approximately monthly through Month 4, every 3 months through Month 24, and every 6 months through Month 60. After completion of the Month 60 visit, SMPA will collect long-term data annually from 6 years to 15 years after DSP-3077 administration to further characterize its long-term safety.
Endpoints and Objectives
The primary objective of the study is evaluating the safety and tolerability of two dose levels of DSP-3077. Secondary endpoints include assessing the safety, engraftment, and potential therapeutic response to DSP-3077, as well as evaluating its delivery device performance.
Company Perspective
"We are encouraged by the potential that iPSCs 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, President and CEO of SMPA. "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."
The estimated primary completion date for this study is October 31, 2028.