Topical Ocular TRPV1 Antagonist SAF312 (Libvatrep) for Postoperative Pain After Photorefractive Keratectomy

Evaluation of safety and efficacy of topical ocular SAF312 (Libvatrep) in post-photorefractive keratectomy (PRK) pain.

In this placebo (vehicle)-controlled, participant- and investigator-masked study, 40 participants were randomized (1:1) to two treatment sequences in a bilateral PRK crossover design (SAF312 2.5% followed by vehicle [or vice versa], one eye drop, four times daily for 72 hours after PRK). Primary endpoints were visual analog scale (VAS) pain scores at 6 hours after first drop of study drug and average VAS scores over 0 to 12 hours postoperatively. Secondary endpoints included postoperative oral rescue medication (ORM) use and adverse events (AEs).

All 40 participants completed the study. Both primary endpoints were met; mean difference in VAS pain scores between SAF312- and vehicle-treated eyes was -11.13 (P = 0.005, -25%) at 6 hours postoperatively and -8.56 (P = 0.017, -22%) over 0 to 12 hours. Mean VAS pain scores with SAF312 were consistently lower than with vehicle from 1 hour postoperatively up to 30 hours (P ≤ 0.10 observed in 8/11 time points). Less ORM was taken with SAF312 up to 0 to 72 hours postoperatively, with a trend of fewer participants taking ORM at 0 to 24 hours postoperatively with SAF312 versus vehicle. No serious AEs were reported. All ocular AEs were mild and transient, and none were drug related. SAF312-treated eyes showed no delay in wound healing and had a lower grade 4 conjunctival hyperemia 24 hours postoperatively versus vehicle-treated eyes.

SAF312 was well tolerated and effective in reducing ocular pain post-PRK.

Topical SAF312 presents a new therapeutic option for patients undergoing PRK.