Who is sponsoring NCT04024891?

NCT04024891 is sponsored by Ocuphire Pharma, Inc..

What drugs are being tested in NCT04024891?

Interventions in NCT04024891: Phentolamine Mesylate Ophthalmic Solution 1%, Phentolamine Mesylate Ophthalmic Solution Vehicle (Placebo).

What condition does NCT04024891 study?

NCT04024891 studies Mydriasis, Dilation.

Is NCT04024891 still recruiting?

NCT04024891 is currently completed. Last updated 29 August 2023.

Are results published for NCT04024891?

Yes — primary outcome results have been posted to ClinicalTrials.gov. See the outcomes section above for details.

Last reviewed 2023-08-29 · How we verify

NCT04024891

Name: Drug Landscape Pharmaceutical Database
Creator: Drug Landscape
Published: 2026-01-01
License: https://creativecommons.org/licenses/by/4.0/

Safety and Efficacy of Ophthalmic Phentolamine Mesylate to Reverse Pharmacologically Induced Mydriasis

Completed Phase 2 Results posted Last updated 29 August 2023

What this trial tests

Phase 2 trial testing Phentolamine Mesylate Ophthalmic Solution 1% in Mydriasis in 32 participants. Completed in 17 September 2019.

Timeline

13 August 2019

Primary endpoint
17 September 2019

17 September 2019

Quick facts

Lead sponsor	Ocuphire Pharma, Inc.
Phase	Phase 2
Status	Completed
Study type	INTERVENTIONAL
Allocation	randomized
Design	crossover
Masking	triple
Primary purpose	treatment
Enrollment	32
Start date	13 August 2019
Primary completion	17 September 2019
Estimated completion	17 September 2019
Sites	4 locations across United States

Drugs / interventions tested

Phentolamine Mesylate Ophthalmic Solution 1% — full drug profile →
Phentolamine Mesylate Ophthalmic Solution Vehicle (Placebo)

Conditions studied

Mydriasis — all drugs for Mydriasis →
Dilation — all drugs for Dilation →

Sponsor

Ocuphire Pharma, Inc. — full company profile →

Who can join

Adults 18 to 45, any sex, with Mydriasis or Dilation. Patients with the condition only — healthy volunteers not accepted.

Results — posted to ClinicalTrials.gov

Per-arm endpoint measurements with 95% confidence intervals where reported. Source: trial results section.

Pupil Diameter (Change From Max) Primary · 2 hours

Change in pharmacologically-induced mydriatic (maximum) pupil diameter at 2 hours post-treatment in the study eye.

Group	Value	95% CI
Phentolamine Mesylate Ophthalmic Solution 1%	-1.69	± 0.117
Phentolamine Mesylate Ophthalmic Solution Vehicle	-0.69	± 0.117

Pupil Diameter (Change From Max) Secondary · 30 min, 1 hours, 4 hours, 6 hours

Change in pharmacologically-induced mydriatic (maximum) pupil diameter at remaining timepoints (30 min, 1 hours, 4 hours, 6 hours)

30 minutes

Group	Value	95% CI
Phentolamine Mesylate Ophthalmic Solution 1%	-0.06	± 0.039
Phentolamine Mesylate Ophthalmic Solution Vehicle	-0.13	± 0.039

1 hour

Group	Value	95% CI
Phentolamine Mesylate Ophthalmic Solution 1%	-0.77	± 0.072
Phentolamine Mesylate Ophthalmic Solution Vehicle	-0.29	± 0.072

4 hours

Group	Value	95% CI
Phentolamine Mesylate Ophthalmic Solution 1%	-2.83	± 0.145
Phentolamine Mesylate Ophthalmic Solution Vehicle	-1.69	± 0.146

6 hours

Group	Value	95% CI
Phentolamine Mesylate Ophthalmic Solution 1%	-3.24	± 0.132
Phentolamine Mesylate Ophthalmic Solution Vehicle	-2.54	± 0.133

Pupil Diameter Return to Baseline Secondary · 0 min, 1 hour, 2 hours, 4 hours, 6 hours

Percent of Subjects Achieving Pupil Diameter No More Than 0.5 mm Above Baseline by Time Point with either phenylephrine or tropicamide

0 min

Group	Value	95% CI
Phentolamine Mesylate Ophthalmic Solution 1%	2
Phentolamine Mesylate Ophthalmic Solution Vehicle	3

1 hour

Group	Value	95% CI
Phentolamine Mesylate Ophthalmic Solution 1%	6
Phentolamine Mesylate Ophthalmic Solution Vehicle	3

2 hour

Group	Value	95% CI
Phentolamine Mesylate Ophthalmic Solution 1%	11
Phentolamine Mesylate Ophthalmic Solution Vehicle	6

4 hour

Group	Value	95% CI
Phentolamine Mesylate Ophthalmic Solution 1%	24
Phentolamine Mesylate Ophthalmic Solution Vehicle	12

6 hour

Group	Value	95% CI
Phentolamine Mesylate Ophthalmic Solution 1%	31
Phentolamine Mesylate Ophthalmic Solution Vehicle	28

Accommodation Measured by the Near Point Rule (Diopters) (Change From Baseline), Percent With Unchanged Accommodation Secondary · 0 min, 2 hours, 4 hours

Change from baseline (-1 hour) in accommodation at each time point (0 min, 2 hours, 4 hours) with Tropicamide and Phenylephrine Worsening of accommodation is defined as an amplitude decrease of greater than 1 diopter compared to baseline

Dilated with Tropicamide, 0 min

Group	Value	95% CI
Phentolamine Mesylate Ophthalmic Solution 1%	3
Phentolamine Mesylate Ophthalmic Solution Vehicle	2
Phentolamine Mesylate Ophthalmic Solution 1%	13
Phentolamine Mesylate Ophthalmic Solution Vehicle	14

Dilated with Tropicamide, 2 hr

Group	Value	95% CI
Phentolamine Mesylate Ophthalmic Solution 1%	7
Phentolamine Mesylate Ophthalmic Solution Vehicle	3
Phentolamine Mesylate Ophthalmic Solution 1%	9
Phentolamine Mesylate Ophthalmic Solution Vehicle	13

Dilated with Tropicamide, 4 hr

Group	Value	95% CI
Phentolamine Mesylate Ophthalmic Solution 1%	11
Phentolamine Mesylate Ophthalmic Solution Vehicle	7
Phentolamine Mesylate Ophthalmic Solution 1%	5
Phentolamine Mesylate Ophthalmic Solution Vehicle	9

Dilated with Phenylephrine, 0 min

Group	Value	95% CI
Phentolamine Mesylate Ophthalmic Solution 1%	10
Phentolamine Mesylate Ophthalmic Solution Vehicle	11
Phentolamine Mesylate Ophthalmic Solution 1%	5
Phentolamine Mesylate Ophthalmic Solution Vehicle	4

Dilated with Phenylephrine, 2 hr

Group	Value	95% CI
Phentolamine Mesylate Ophthalmic Solution 1%	11
Phentolamine Mesylate Ophthalmic Solution Vehicle	13
Phentolamine Mesylate Ophthalmic Solution 1%	4
Phentolamine Mesylate Ophthalmic Solution Vehicle	2

Dilated with Phenylephrine, 4 hr

Group	Value	95% CI
Phentolamine Mesylate Ophthalmic Solution 1%	12
Phentolamine Mesylate Ophthalmic Solution Vehicle	13
Phentolamine Mesylate Ophthalmic Solution 1%	3
Phentolamine Mesylate Ophthalmic Solution Vehicle	2

Conjunctival Hyperemia (Eye Redness) Assessed Visually With the Brien Holden Vision Institute (Formerly Corneal and Contact Lens Research Unit, or CCLRU) Bulbar Redness Scale (0-3) Secondary · 0 min, 30 min, 1 hour, 2 hours, 4 hours, 6 hours

Conjunctival hyperemia at each timepoint (0 min, 30 min, 1 hour, 2 hours, 4 hours, 6 hours), for study eye; in all subjects. Scale 0-3 (None, Mild, Moderate, Severe)

Baseline (-1 hr)

Group	Value	95% CI
Phentolamine Mesylate Ophthalmic Solution 1%	0.45	± 0.568
Phentolamine Mesylate Ophthalmic Solution Vehicle	0.35	± 0.486

0 min

Group	Value	95% CI
Phentolamine Mesylate Ophthalmic Solution 1%	0.23	± 0.497
Phentolamine Mesylate Ophthalmic Solution Vehicle	0.29	± 0.461

30 min

Group	Value	95% CI
Phentolamine Mesylate Ophthalmic Solution 1%	1.52	± 0.677
Phentolamine Mesylate Ophthalmic Solution Vehicle	0.42	± 0.502

1 hr

Group	Value	95% CI
Phentolamine Mesylate Ophthalmic Solution 1%	1.55	± 0.675
Phentolamine Mesylate Ophthalmic Solution Vehicle	0.45	± 0.568

2 hr

Group	Value	95% CI
Phentolamine Mesylate Ophthalmic Solution 1%	1.42	± 0.620
Phentolamine Mesylate Ophthalmic Solution Vehicle	0.45	± 0.568

4 hr

Group	Value	95% CI
Phentolamine Mesylate Ophthalmic Solution 1%	1.10	± 0.539
Phentolamine Mesylate Ophthalmic Solution Vehicle	0.42	± 0.564

6 hr

Group	Value	95% CI
Phentolamine Mesylate Ophthalmic Solution 1%	0.81	± 0.654
Phentolamine Mesylate Ophthalmic Solution Vehicle	0.35	± 0.486

Best Corrected Distance Visual Acuity (BCDVA) Measured by Early Treatment Diabetic Retinopathy Study (ETDRS) Light Box Chart (Letters) at 4 Meters (Change From Baseline) Secondary · 0 mins, 30 mins, 1 hour, 2 hours, 4 hours, 6 hours

Change from baseline (-1 hour) in Best Corrected Distance Visual Acuity at each time point (0 min, 30 mins, 1 hour, 2 hours, 6 hours) in Study Eye

0 mins

Group	Value	95% CI
Phentolamine Mesylate Ophthalmic Solution 1%	-0.45	± 2.142
Phentolamine Mesylate Ophthalmic Solution Vehicle	-0.81	± 2.182

30 mins

Group	Value	95% CI
Phentolamine Mesylate Ophthalmic Solution 1%	-0.55	± 2.188
Phentolamine Mesylate Ophthalmic Solution Vehicle	-0.55	± 1.690

1 hour

Group	Value	95% CI
Phentolamine Mesylate Ophthalmic Solution 1%	0.29	± 1.774
Phentolamine Mesylate Ophthalmic Solution Vehicle	-0.10	± 2.797

2 hours

Group	Value	95% CI
Phentolamine Mesylate Ophthalmic Solution 1%	0.65	± 2.727
Phentolamine Mesylate Ophthalmic Solution Vehicle	0.16	± 2.162

4 hours

Group	Value	95% CI
Phentolamine Mesylate Ophthalmic Solution 1%	1.06	± 2.205
Phentolamine Mesylate Ophthalmic Solution Vehicle	0.10	± 2.119

6 hours

Group	Value	95% CI
Phentolamine Mesylate Ophthalmic Solution 1%	0.45	± 3.982
Phentolamine Mesylate Ophthalmic Solution Vehicle	0.90	± 2.399

Distance-Corrected Near Visual Acuity (DCNVA) Measured by Standard Reading Card (Original Series Sloan Letter ETDRS Card at 16 Inches, LogMAR Units) (Change From Baseline) Secondary · 0 mins, 30 mins, 1 hour, 2 hours, 4 hours, 6 hours

Change from baseline (-1 hour) in Distance Corrected Near Visual Acuity at each time point (0 min, 30 mins, 1 hour, 2 hours, 6 hours) in Study Eye

0 mins

Group	Value	95% CI
Phentolamine Mesylate Ophthalmic Solution 1%	0.14	± 0.194
Phentolamine Mesylate Ophthalmic Solution Vehicle	0.13	± 0.216

30 mins

Group	Value	95% CI
Phentolamine Mesylate Ophthalmic Solution 1%	0.09	± 0.156
Phentolamine Mesylate Ophthalmic Solution Vehicle	0.09	± 0.217

1 hour

Group	Value	95% CI
Phentolamine Mesylate Ophthalmic Solution 1%	0.05	± 0.146
Phentolamine Mesylate Ophthalmic Solution Vehicle	0.07	± 0.142

2 hours

Group	Value	95% CI
Phentolamine Mesylate Ophthalmic Solution 1%	0.03	± 0.113
Phentolamine Mesylate Ophthalmic Solution Vehicle	0.00	± 0.087

4 hours

Group	Value	95% CI
Phentolamine Mesylate Ophthalmic Solution 1%	0.00	± 0.075
Phentolamine Mesylate Ophthalmic Solution Vehicle	0.01	± 0.079

6 hours

Group	Value	95% CI
Phentolamine Mesylate Ophthalmic Solution 1%	-0.02	± 0.083
Phentolamine Mesylate Ophthalmic Solution Vehicle	0.00	± 0.055

Adverse events — posted to ClinicalTrials.gov

Time frame: 2 weeks.. Reporting threshold: 0%. Adverse-event reports describe events observed during the trial — not all are caused by the drug.

Phentolamine Mesylate Ophthalmic Solution 1%

Serious: 0/31 (0%)

Deaths: 0/31

Phentolamine Mesylate Ophthalmic Solution Vehicle

Serious: 0/32 (0%)

Deaths: 0/32

Other adverse events (3 terms — click to expand)

Reaction	System	Phentolamine Mesylate Opht…	Phentolamine Mesylate Opht…
Conjunctival Hyperemia	Eye disorders	—	—
Abdominal Pain, Upper	Gastrointestinal disorders	—	—
Nausea	Gastrointestinal disorders	—	—

Data from ClinicalTrials.gov NCT04024891 adverse events section.

Sponsor's own description

The objectives of this study are: * To evaluate the efficacy of Nyxol (phentolamine mesylate ophthalmic solution 1%) to expedite the reversal of pharmacologic mydriasis * To evaluate the safety of Nyxol * To evaluate the effect of Lumify® to suppress conjunctival hyperemia (redness) potentially associated with administration of Nyxol

Publications & conference data

1 peer-reviewed publication reference this trial (live from Europe PMC):

Role of adrenergic receptor signalling in neuroimmune communication.
Chhatar S, Lal G. · · 2021 · cited 76× · PMID 35492402 · DOI 10.1016/j.crimmu.2021.11.001

Verify or expand the search:

Other Ocuphire Pharma, Inc. trials

Trials by the same sponsor.

NCT06542497 — Evaluate Efficacy and Safety of POS to Improve Distance-corrected Near Visual in Participants With Presbyopia · Phase 3 · completed
NCT06349759 — Safety and Efficacy of 0.75% Phentolamine Ophthalmic Solution in Subjects With Post-refractive Surgery Visual Disturbanc · Phase 3 · completed
NCT05646719 — Safety and Efficacy of Nyxol Eye Drops as a Single Agent and With Adjunctive Low-Dose Pilocarpine Eye Drops in Subjects · Phase 3 · completed
NCT05223478 — Nyxol (0.75% Phentolamine Ophthalmic Solution) to Reverse Pharmacologically-Induced Mydriasis in Pediatric Subjects · Phase 3 · completed
NCT05134974 — Safety and Efficacy of Nyxol (0.75% Phentolamine Ophthalmic Solution) to Reverse Pharmacologically-Induced Mydriasis (MI · Phase 3 · completed

Verify against primary sources

ClinicalTrials.gov — authoritative US registry record
WHO ICTRP — international registry index
EU Clinical Trials Register
Sponsor press releases (Google)

Data sources for this page

Trial protocol + status: ClinicalTrials.gov NCT04024891 (US National Library of Medicine, public domain)
Publications: Europe PMC API search by NCT ID, retrieved 10 June 2026
Drug + disease cross-links: matched in real time against Drug Landscape's normalised drug + company + condition tables
Sponsor: as reported to ClinicalTrials.gov by Ocuphire Pharma, Inc.
Last refreshed: 29 August 2023

Drug Landscape aggregates and links these public records for informational use only. Always verify against the primary source before clinical or regulatory decisions. Canonical URL: https://druglandscape.com/trial/NCT04024891.

Primary sources · FDA · ClinicalTrials.gov · EMA · SEC EDGAR · ChEMBL · Wikidata · full sourcing

NCT04024891

Quick facts

Drugs / interventions tested

Conditions studied

Sponsor

Who can join

Results — posted to ClinicalTrials.gov

Adverse events — posted to ClinicalTrials.gov

Sponsor's own description

Publications & conference data

Related trials

Other trials of Phentolamine Mesylate Ophthalmic Solution 1%

Other Ocuphire Pharma, Inc. trials

Verify against primary sources