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Phentolamine eye drops for adults with reduced night vision after keratorefractive surgery

RANDOMIZED, PLACEBO-CONTROLLED, DOUBLE-MASKED STUDY OF THE SAFETY AND EFFICACY OF POS (0.75% PHENTOLAMINE OPHTHALMIC SOLUTION) IN PARTICIPANTS WITH PREVIOUS KERATOREFRACTIVE SURGERY WITH DECREASED VISUAL ACUITY UNDER MESOPIC CONDITIONS

Phase 3 Interventional Ocuphire Pharma, Inc. · NCT07140783

This will test whether nightly phentolamine eye drops can improve low-light (mesopic) vision in adults who developed decreased vision after keratorefractive surgery.

Quick facts

PhasePhase 3
Study typeInterventional
Enrollment200 (estimated)
Ages18 Years and up
SexAll
SponsorOcuphire Pharma, Inc. Industry-sponsored
Locations23 sites (Chandler, Arizona and 22 other locations)
Trial IDNCT07140783 on ClinicalTrials.gov

What this trial studies

This randomized, double-masked, placebo-controlled Phase 3 study compares 0.75% phentolamine ophthalmic solution to a placebo in adults with decreased mesopic visual acuity after keratorefractive surgery. Participants self-administer a nightly study drop for two weeks, keep a dosing diary, and return for weekly clinic visits for visual testing and safety checks. The trial measures changes in mesopic visual acuity and records safety and tolerability outcomes. Eligibility requires prior keratorefractive surgery with onset of night-vision symptoms within two months of surgery and a mesopic pupil diameter of at least 5 mm in the study eye.

Who should consider this trial

Good fit: Adults (≥18) who had keratorefractive surgery more than six months ago, developed night-vision disturbances within two months after surgery, and meet mesopic pupil and visual acuity criteria in the same eye are ideal candidates.

Not a fit: Patients whose night-vision problems began for reasons unrelated to their refractive surgery or who do not meet the mesopic pupil diameter and visual acuity requirements are unlikely to receive benefit from this treatment.

Why it matters

Potential benefit: If successful, the eye drops could improve night-time vision and reduce glare, halos, or starbursts for patients who developed decreased mesopic acuity after refractive surgery.

How similar studies have performed: Early-phase data and pilot work have suggested phentolamine may improve low-light vision after refractive surgery, but definitive phase 3 evidence is still pending.

Eligibility criteria

Show full inclusion / exclusion criteria 
Inclusion Criteria:

1. Males or females ≥ 18 years of age
2. Previous history (\>6 months prior to Screening) of keratorefractive surgery (eg, PRK, LASIK, SMILE, and RK/astigmatic keratotomy \[AK\]/limbal-relaxing incisions \[LRI\]) in one or both eyes and have participant-reported night vision disturbances (eg, glare, halos, and/or starbursts). Symptoms must have been first noted within 2 months following keratorefractive surgery
3. Able to independently comply with all protocol-mandated procedures and to attend all scheduled office visits
4. Able and willing to give written consent to participate in this study
5. Able to self-administer study medication

   Inclusion criteria #6, #7, and #8 must all be met in the same eye:
6. PD ≥ 5 mm under mesopic conditions in at least 1 eye. This test may be repeated once, following an additional 5 min of dark adaptation to the mesopic light conditions if the initial results do not meet this criterion
7. mLCVA ≤ 30 Early Treatment Diabetic Retinopathy Study (ETDRS) letters (20/63 Snellen or worse) in at least 1 eye using the Precision Vision Illuminator Cabinet with 5% translucent contrast chart and a mesopic filter at 4 m
8. ≥ 10 ETDRS letters improvement in mLCVA in at least 1 eye during illumination of the contralateral eye with a Brightness Acuity Tester (BAT) system on the low setting using the Precision Vision Illuminator Cabinet with 5% translucent contrast chart and a mesopic filter at 4 m

Exclusion Criteria:

Ophthalmic (in either eye unless otherwise noted):

1. Prior unresolved dry eye diagnosis, taking prescription medication for dry eye (eg, drops, nasal sprays \[Tyrvaya®\], etc.), or taking artificial tear drops routinely for dry eye
2. Prior history of fluctuating vision
3. Clinically significant ocular disease as deemed by the Investigator (eg, untreated visually significant cataract, glaucoma, corneal edema, uveitis, severe keratoconjunctivitis sicca, retina degeneration, loss of visual field due to glaucoma or stroke, branch retinal vein occlusion, retina flare) that might interfere with the study
4. History or presence of corneal endothelial dystrophy (eg, Fuchs' dystrophy or presence of guttae)
5. Known hypersensitivity to any topical alpha-adrenoceptor antagonists
6. Known allergy or contraindication to any component of the vehicle formulation
7. History of cauterization of the punctum or punctal plug (silicone or collagen) insertion or removal in the study eye
8. Pseudophakic participants with extended depth-of-focus or multifocal intraocular lenses (IOLs)
9. Ocular trauma, ocular surgery (eg, IOLs), or laser procedure (eg, LASIK, PRK, SMILE, and RK/AK/LRI) within 6 months prior to Screening
10. Use of any topical prescription or over-the-counter (OTC) ophthalmic medications of any kind (including artificial tear drops) within 7 days prior to Screening until study completion, with the exception of lid scrubs with OTC products (eg, OCuSOFT® lid scrub, SteriLid®, baby shampoo, etc.)
11. Recent or current evidence of ocular infection or inflammation (such as current evidence of clinically significant blepharitis, conjunctivitis, or a history of herpes simplex keratitis or herpes zoster keratitis at Screening). Participants must be symptom free for at least 7 days prior to Screening
12. History of diabetic retinopathy, diabetic macular edema, or dry or wet macular degeneration in the study eye
13. History of any traumatic (surgical or nonsurgical) or nontraumatic condition affecting the pupil or iris (eg, irregularly shaped pupil, neurogenic pupil disorder, iris atrophy, iridotomy, iridectomy, etc.)
14. Unwilling or unable to discontinue use of contact lenses at least 1 hour prior to Screening for soft contact lenses or at least 8 hours prior to Screening for hard gas-permeable contact lenses, and at least 8 hours (for both types of lenses) prior to all other office visits
15. Previously undiagnosed dry eye, at the determination of the Investigator. Dry eye diagnosis should be based on one of the following dry eye test results: tear break-up time \< 5 seconds, or corneal fluorescein staining ≥ Grade 2 in the inferior zone or ≥ Grade 1 in the central zone using the National Eye Institute scale

    Systemic:
16. Known hypersensitivity or contraindication to alpha- and/or beta-adrenoceptor antagonists
17. Clinically significant systemic disease (eg, severe diabetes, myasthenia gravis, cancer, hepatic, renal, endocrine, or cardiovascular disorders) that might interfere with the study
18. Initiation of treatment with or any changes to the current dosage, drug, or regimen of any systemic adrenergic or cholinergic drugs within 7 days prior to Screening or during the study
19. Participation in any investigational study within 30 days prior to Screening or during the study
20. Participation in any investigational study using POS
21. Females of childbearing potential who are pregnant, nursing, planning a pregnancy during the study, or not using a medically acceptable form of birth control. Acceptable methods include the use of at least one of the following: intrauterine device, hormonal contraception (oral, injection, patch, implant, ring), barrier with spermicide (condom, diaphragm), or abstinence. A female is considered to be of childbearing potential unless she is 1 year postmenopausal or 3 months post-surgical sterilization. All females of childbearing potential, including those post-tubal ligation, must have a negative urine pregnancy test result at each visit
22. Resting HR outside 50 to 110 beats per min at Screening. HR may be repeated only once if outside the specified range, following at least a 5-min rest period in the sitting position
23. Hypertension with resting diastolic BP \> 105 mmHg or systolic BP \> 160 mmHg at Screening. BP may be repeated only once if outside the specified range, following at least a 5-min rest period in the sitting position

Where this trial is running

Chandler, Arizona and 22 other locations

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
View on ClinicalTrials.gov → Find more trials like this →
Conditions Vision Loss NightVision Disorderskeratorefractive surgerydecreased visual acuityvision disordermesopic lightingnight vision
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.