A Phase 3 interventional study of Phentolamine Ophthalmic Solution 0.75% and Phentolamine Ophthalmic Solution Vehicle in Mydriasis and Dilation, sponsored by Opus Genetics, Inc. Completed at 2 sites in United States. Open to participants aged 3 Years to 11 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-10-30.
Sponsored by Opus Genetics, Inc · Phase 3, Interventional, and Treatment
The objectives of this study are:
This is a randomized, parallel-arm, double-masked, placebo-controlled study in approximately 20 randomized pediatric subjects evaluating the safety and efficacy of Nyxol in pediatric subjects with pharmacologically induced mydriasis with three dilating agents (e.g., phenylephrine, tropicamide, and Paremyd). Pediatric subjects will be recruited for the study into 2 age groups as follows:1) 3 to 5 years of age: 10 subjects 2) 6 to 11 years of age: 10 subjects.
37 studies on the registry are indexed under Mydriasis; 4 are open to participants now.
This study's enrollment of 23 is below the median of 61 across 35 interventional studies indexed under Mydriasis.
Browse Mydriasis studies →Opus Genetics, Inc is the lead sponsor of 17 studies on the registry; 4 are open to participants now.
Of its 13 completed or terminated interventional studies of FDA-regulated products, 13 (100%) have results posted.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Known allergy, , or to any component of the phentolamine ophthalmic solution or to any component of the mydriatic agents or vehicle formulation
Systemic:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
One drop of study medication in each eye.
Drug: Phentolamine Ophthalmic Solution 0.75%
One drop of study medication in each eye.
Drug: Phentolamine Ophthalmic Solution Vehicle
0.75% phentolamine ophthalmic solution (Nyxol), a non-selective alpha-1 and alpha-2 adrenergic antagonist
Also known as: Nyxol®, Nyxol
Phentolamine Ophthalmic Solution Vehicle
Safety Measurements
Study Eye Change from Baseline (-1 Hour) Conjunctival Hyperemia Grading; Cornea and Contact Lens Research Unit (CCLRU scale) Grades range from 0 to 3, with 3 being considered the most severe.
Time frame: 0 Minutes, 90 Minutes, 3 Hours, 24 Hours
Vital Signs
Change from Screening Heart Rate
Time frame: 3 Hours, 24 Hours
Vital Signs
Change from Screening Blood Pressure (Systolic)
Time frame: 3 Hours, 24 Hours
Safety Measurement
Study Eye Change from Baseline (-1 Hour) in Best Corrected Distance Visual Acuity
Time frame: 0 Minutes, 3 Hours, 24 Hours
Change From Screening Blood Pressure (Diastolic)
Time frame: 3 Hours, 24 Hours
Efficacy Measurement: Pupil Diameter
Percentage of Subjects Returning to ≤ 0.2 mm from Baseline (-1 hour) Pupil Diameter (Study Eye)
Time frame: 90 Minutes, 3 Hours, and 24 Hours
Efficacy Measurement: Pupil Diameter
Change (in mm) in Pupil Diameter from Max Pupil Dilation (0 minutes) (Study Eye)
Time frame: 90 Minutes, 3 Hours, and 24 Hours
Efficacy Measurement: Pupil Diameter
Time (Hours) to Return to ≤ 0.2 mm from Baseline (-1 Hour) Pupil Diameter (Time-savings Analysis) (Study Eye)
Time frame: Up to 24 Hours
| Milestone | Phentolamine Ophthalmic Solution 0.75% | Phentolamine Ophthalmic Solution Vehicle |
|---|---|---|
| Started | 11 | 12 |
| Completed | 11 | 12 |
| Not completed | 0 | 0 |
Study Eye Change from Baseline (-1 Hour) Conjunctival Hyperemia Grading; Cornea and Contact Lens Research Unit (CCLRU scale) Grades range from 0 to 3, with 3 being considered the most severe.
| score on a scale | Phentolamine Ophthalmic Solution 0.75% | Phentolamine Ophthalmic Solution Vehicle |
|---|---|---|
| 0 Minutes | 0.3 ± 0.65 | -0.2 ± 0.58 |
| 90 Minutes | 1.6 ± 0.50 | 0.0 ± 0.43 |
| 3 Hours | 1.1 ± 0.54 | -0.1 ± 0.29 |
| 24 Hours | 0.1 ± 0.30 | -0.2 ± 0.58 |
Change from Screening Heart Rate
| beats per minute | Phentolamine Ophthalmic Solution 0.75% | Phentolamine Ophthalmic Solution Vehicle |
|---|---|---|
| 3 Hours | -1.1 ± 7.92 | -2.0 ± 14.24 |
| 24 Hours | -2.5 ± 10.10 | -3.5 ± 12.69 |
Change from Screening Blood Pressure (Systolic)
| mmHg | Phentolamine Ophthalmic Solution 0.75% | Phentolamine Ophthalmic Solution Vehicle |
|---|---|---|
| 3 Hours | -4.6 ± 8.91 | -0.8 ± 12.39 |
| 24 Hours | -2.8 ± 7.48 | -5.8 ± 6.98 |
Study Eye Change from Baseline (-1 Hour) in Best Corrected Distance Visual Acuity
| letters | Phentolamine Ophthalmic Solution 0.75% | Phentolamine Ophthalmic Solution Vehicle |
|---|---|---|
| 0 Minutes | -1.2 ± 1.66 | -0.3 ± 1.23 |
| 3 Hours | 1.2 ± 1.89 | 0.1 ± 0.67 |
| 24 Hours | 1.5 ± 1.97 | 0.7 ± 1.15 |
| mmHg | Phentolamine Ophthalmic Solution 0.75% | Phentolamine Ophthalmic Solution Vehicle |
|---|---|---|
| 3 Hours | -2.4 ± 9.72 | 1.0 ± 15.68 |
| 24 Hours | -1.1 ± 11.63 | -3.8 ± 7.96 |
Percentage of Subjects Returning to ≤ 0.2 mm from Baseline (-1 hour) Pupil Diameter (Study Eye)
| Participants | Phentolamine Ophthalmic Solution 0.75% | Phentolamine Ophthalmic Solution Vehicle |
|---|---|---|
| 90 Minutes | 7 | 3 |
| 3 Hours | 9 | 4 |
| 24 Hours | 10 | 6 |
Change (in mm) in Pupil Diameter from Max Pupil Dilation (0 minutes) (Study Eye)
| millimeters | Phentolamine Ophthalmic Solution 0.75% | Phentolamine Ophthalmic Solution Vehicle |
|---|---|---|
| 90 Minutes | -1.475 ± 0.7188 | -0.378 ± 0.4473 |
| 3 Hours | -2.031 ± 0.6919 | -0.723 ± 0.6470 |
| 24 Hours | -2.005 ± 1.2841 | -1.44 ± 1.2891 |
Time (Hours) to Return to ≤ 0.2 mm from Baseline (-1 Hour) Pupil Diameter (Time-savings Analysis) (Study Eye)
| hours | Phentolamine Ophthalmic Solution 0.75% | Phentolamine Ophthalmic Solution Vehicle |
|---|---|---|
| Efficacy Measurement: Pupil Diameter | 2.95 ± 2.564 | 5.54 ± 3.078 |
Collected over 2 Days. Non-serious events are listed at a 0% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Phentolamine Ophthalmic Solution 0.75% | 0/11 (0%) | 0/11 (0%) | 0/11 (0%) |
| Phentolamine Ophthalmic Solution Vehicle | 0/12 (0%) | 0/12 (0%) | 0/12 (0%) |
| Age, Categorical(Participants) | Phentolamine Ophthalmic Solution 0.75% | Phentolamine Ophthalmic Solution Vehicle | Total |
|---|---|---|---|
| <=18 years | 11 | 12 | 23 |
| Between 18 and 65 years | 0 | 0 | 0 |
| >=65 years | 0 | 0 | 0 |
| Age, Continuous(years) | Phentolamine Ophthalmic Solution 0.75% | Phentolamine Ophthalmic Solution Vehicle | Total |
|---|---|---|---|
| Mean | 6.9 ± 2.74 | 5.8 ± 2.66 | 6.3 ± 2.69 |
| Sex: Female, Male(Participants) | Phentolamine Ophthalmic Solution 0.75% | Phentolamine Ophthalmic Solution Vehicle | Total |
|---|---|---|---|
| Female | 5 | 7 | 12 |
| Male | 6 | 5 | 11 |
| Ethnicity (NIH/OMB)(Participants) | Phentolamine Ophthalmic Solution 0.75% | Phentolamine Ophthalmic Solution Vehicle | Total |
|---|---|---|---|
| Hispanic or Latino | 2 | 1 | 3 |
| Not Hispanic or Latino | 9 | 11 | 20 |
| Unknown or Not Reported | 0 | 0 | 0 |
| Race (NIH/OMB)(Participants) | Phentolamine Ophthalmic Solution 0.75% | Phentolamine Ophthalmic Solution Vehicle | Total |
|---|---|---|---|
| American Indian or Alaska Native | 0 | 0 | 0 |
| Asian | 0 | 0 | 0 |
| Native Hawaiian or Other Pacific Islander | 0 | 0 | 0 |
| Black or African American | 0 | 2 | 2 |
| White | 11 | 10 | 21 |
| More than one race | 0 | 0 | 0 |
| Unknown or Not Reported | 0 | 0 | 0 |
| Region of Enrollment(participants) | Phentolamine Ophthalmic Solution 0.75% | Phentolamine Ophthalmic Solution Vehicle | Total |
|---|---|---|---|
| United States | 11 | 12 | 23 |
PDFs hosted by the registry, ClinicalTrials.gov.
Plan to share: No
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is completed, as verified in Aug 2023. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: Phentolamine
Opus Genetics, Inc