Study finds TTHX1114 enhances visual recovery, corneal deturgescence after DSO

TTHX1114, an engineered FGF1, when administered in a dose-responsive manner, can enhance the rate of visual recovery and corneal deturgescence following Descemet stripping only (DSO), according to data presented at ASCRS 2023. Smaller descemetorhexis was associated with a faster recovery, while the presence of comorbid diabetes appeared to delay recovery. Notably, visual outcomes were not adversely affected by concurrent cataract surgery in patients undergoing DSO.

The study included 64 eyes from 49 patients. Patients were assigned to treatment based on the discretion of the Investigator, with 3 active dose regimens utilized: low-dose repeat administration (Group 2), high-dose single-administration (Group 3), and high-dose repeat administration (Group 4). BCVA Responder was defined as achieving a BCVA of 20/40 or better after DSO, while CCT Responder was defined as achieving a post-DSO CCT measurement lower than the pre-DSO measurement.

The study found a dose effect, with the low-dose group (Group 2) showing differences in efficacy compared to the high-dose groups (Groups 3 and 4) in terms of both best-corrected visual acuity (BCVA) and central corneal thickness (CCT). The efficacy observed in Groups 3 and 4 was similar, leading to the pooling of all eyes in these groups (52 eyes) to further evaluate the impact of covariates on efficacy.

The results of the study indicate that patients with smaller DSO experienced a faster time (in weeks) to achieve a BCVA of 20/40 or better (4mm = 4.5 weeks, 4.5mm = 6.7 weeks, ≥5mm = 6.3 weeks). Conversely, subjects with diabetes exhibited a slower recovery time (7.7 weeks) compared to subjects without diabetes (5.2 weeks).

The study did not find any significant differences in visual recovery between subjects who underwent combination cataract surgery alongside DSO and those who underwent DSO alone.

Adverse events reported during the study were primarily mild to moderate, and none were considered to be related to the study drug.

“Our increasing body of clinical evidence continues to support our hypothesis that FGF1 leverages the inherent regenerative properties of corneal endothelial and epithelial cells with TTHX1114 to restore vision. We are excited to continue to build on our research demonstrating the safety and efficacy of TTHX1114 in scenarios where patients with endothelial compromise undergo ocular surgery,” said David Eveleth, PhD, President and CEO of Trefoil Therapeutics in a company press release.

Reference
Baartman B, et al. A Phase 2 Study of an Engineered Fibroblast Growth Factor (FGF) to Accelerate Visual Recovery after Descemet Stripping Only (DSO). Presented at: ASCRS 2023.