Regeneration of Corneal Endothelial Cells using pH Pharma’s ROCK Inhibitors presented at ARVO Annual Meeting

Results showing corneal endothelial cell regeneration with sovesudil (starting phase III clinical trial for glaucoma; also known as PHP-201) and PHP-961 was presented at the Association for Research in Vision and Ophthalmology Annual Meeting May 1st – 5th, 2022 (ARVO 2022). This study was conducted at Hallym University in collaboration with pH Pharma. The study demonstrated the potential use of sovesudil and PHP-961 in corneal diseases.


  • No toxicity detected with ROCK inhibitors
  • Increased proliferation of corneal endothelial cells with ROCK inhibitors
  • Increased adhesion of corneal endothelial cells with ROCK inhibitors

“Novel ROCK Inhibitors on the Regeneration of Corneal Endothelial Cells” (link)

Presenter: Young Joo Shin

Purpose: The cornea may lose transparency and cause blindness when Human corneal endothelial cells (HCEnCs) are damaged or diseased. Replacing diseased cells with a healthy donor endothelium is the only currently available treatment. There is increasing interest in the development of cultured graft substitutes and artificial corneas due to the global shortage of donor corneas. The aim of the study is to investigate whether novel Rho-kinase (ROCK) inhibitors can aid in the cultivation and regeneration of HCEnCs.

Methods: HCEnCs were cultured and treated with Y-27632 (Y0503, Sigma-Aldrich), sovesudil (pH Pharma), or PHP-961 (pH Pharma) for 24h. We observed cellular responses, including cell viability, cytotoxicity, proliferation and Ki67 expression with ROCK inhibitors. We also assessed wound healing and cell adhesion assays. Porcine corneas were used ex vivo to evaluate wound healing and regeneration effects of Y-27632, sovesudil, and PHP-961. We performed live/dead cell assays and immunofluorescence staining (for SOX2, b-catenin, and ZO-1) on porcine corneas treated with ROCK inhibitors.

Results: Cell viability, BrdU proliferation assay, and number of Ki67-positive cells was higher in Y-27632, sovesudil and PHP-961 treated compared with control (p<0.05). There was no difference in LDH cytotoxicity test between any groups. Cells treated with Y-27632, sovesudil and PHP-961 showed faster migration, wound healing, and cell adhesion. In the porcine ex vivo experiments, wound healing, the number of live cells, and SOX-positive cells were higher in Y-27632, sovesudil and PHP-961 treated corneas (p<0.05). Across all experiments, the results of sovesudil and PHP-961 were equal or superior to the results of the ROCK inhibitor positive-control, Y-27632.

Conclusions: Novel ROCK inhibitors have a capacity to regenerate HCEnCs through enhancing the cell proliferation and adhesion between cells.