Phentolamine Ophthalmic Solution Reverses Mydriasis Faster, suggests study

Mydriasis, or pharmacologically-induced dilation of the pupils, lasts for up to 24 hours and causes some side effects to include photophobia and blurred vision that can interfere with activities on a day-to-day basis. Developing phentolamine ophthalmic solution 0.75% serves to fill the gap that brings the patient out of the comfort zone much sooner than mydriasis, once again after examination and diagnostic procedures by an eye care specialist.

MIRA-2 and MIRA-3 were Phase 3, two randomized, double-masked, placebo-controlled, multi-center studies designed to evaluate the efficacy and safety of phentolamine ophthalmic solution 0.75% in reversing pharmacologically induced mydriasis. In total, 553 healthy subjects aged between 12 and 80 years enrolled for the study that included subjects who received the assigned, blinded treatment at randomization with either the phentolamine solution or placebo after the pupils had been pharmacologically dilated.

Phentolamine ophthalmic solution 0.75% was significantly better than placebo at terminating mydriasis, according to the results of achieving two of the major endpoints of the studies.

• In MIRA-2, pupil diameter reversal within 90 minutes was seen in 48.9% of patients in the phentolamine solution arm compared with 6.6% in the placebo group (P < 0.0001).

• In MIRA-3, 58% of patients in the phentolamine arm had pupil reversal at 90 minutes compared with 6% in the placebo arm (P < 0.0001).

Both studies showed the reversal of early mydriasis

• MIRA-2: At 60 minutes, 24.5% of patients in the phentolamine-treated group showed reversal compared with only 5.5% in the placebo group (P < 0.0003).

• MIRA-3: At 60 minutes, 42% of patients in the phentolamine-treated group showed reversal compared with only 2% in the placebo group (P < 0.0001).

• At 24 hours post-dilation, only 8-11% of patients in the phentolamine-treated group had residual dilation compared with 28-34% in the placebo group (P < 0.0001).

Phentolamine ophthalmic solution 0.75% reverses pharmacologically induced mydriasis within 60 to 90 minutes with faster recovery from dilation compared with placebo, and is seen to be well-tolerated. These results, as reported in MIRA-2 and MIRA-3, may provide an additional treatment for the patient who needs more rapid resolution of visual disturbances from mydriasis. Substantially effective with FDA approval, phentolamine could soon improve the quality of ophthalmology care.

Reference:

Pepose JS, Wirta D, Evans D, et al. Reversal of Pharmacologically Induced Mydriasis with Phentolamine Ophthalmic Solution. Ophthalmology. Published online September 16, 2024. doi:10.1016/j.ophtha.2024.09.010