The goal of this clinical trial is to show non-inferiority of the MIMS® device/procedure with Mitomycin-C, in terms of its surgical success rate, compared to trabeculectomy with Mitomycin-C in subjects diagnosed with primary open angle glaucoma, whose intraocular pressure is not controlled despite polypharmacy.

Eligible screened participants will undergo the MIMS® procedure and will be followed for a period of 12 months in this single-arm study. Investigators will compare the results of this study to the surgical success rate of traditional trabeculectomy with Mitomycin-C.

Inclusion Criteria:

1. Male or female, ≥ 40 years to ≤ 85 years old

2. Inadequately controlled primary open angle glaucoma with screening mean diurnal IOP of ≥ 21 mmHg and ≤ 40 mmHg despite polypharmacy

3. Primary open angle glaucoma diagnosis based on:

   1. Visual field mean deviation of -3dB or worse and
   2. Glaucomatous optic nerve damage as evidenced by optic disc or retinal nerve fiber layer structural abnormalities documented on slit lamp stereo biomicroscopy or in stereo disc photos

4. Presence of healthy, free, and mobile conjunctiva in the target quadrant

5. Prior ab interno conjunctival-sparing glaucoma procedures were conducted more than 6 months prior to enrollment (e.g., iStent, Trabectome, gonioscopy-assisted transluminal trabeculectomy [GATT])

6. Subject is able and willing to attend all scheduled follow-up exams

7. Subject understands and signs the informed consent

This clinical study is observer masked only when measuring intraocular pressure (using Goldmann Applanation Tonometry). Intraocular pressure measurements will be determined using the 2-person method to reduce bias. Observer 1 (masked to real time reading) will look through the slit lamp and turn the Goldmann Tonometer dial, and Observer 2 will read and record the intraocular pressure readings. Observer 1 will be unable to see the readings with the use of a masking card.