Inclusion Criteria:

1. Patients who have been recently diagnosed (within the last 12 months) with early to moderate open-angle glaucoma (OAG) in at least one eye (including primary OAG, normal tension glaucoma (NTG) and pseudoexfoliation glaucoma)
2. Open angle on gonioscopy
3. Adults aged 18 years or over
4. Snellen visual acuity 6/12 or better in at least one eye meeting the visual field (VF) criteria
5. Visual Field (VF) mean deviation (MD) no worse than -12dB in either eye
6. A negative pregnancy test result at the screening and baseline visit prior to randomisation for women of childbearing potential
7. Ability to provide informed consent to participate
8. Able and willing to attend trial visits and comply with trial procedures for the duration of the trial

Exclusion Criteria:

1. Pigment dispersion glaucoma

2. Pregnancy (or planned pregnancy during the trial) and/or breastfeeding

3. Women of childbearing potential and male participants with a partner of childbearing potential not willing to use highly effective contraception for the duration of the trial treatment and for the time period specified following last trial treatment administration.

4. Current treatment with either isoniazid, pyrazinamide, carbamazepine, phenobarbital or primidone

5. Current liver disease or laboratory results with elevated levels of liver transaminases (AST or ALT >3 x ULN) at screening visit.

6. Renal failure (eGFR <30mL/min/1.73m²) at screening visit.

7. Conditions affecting both eyes which may affect the Visual Field test result:

   1. Diabetic retinopathy or any other retinal disease causing VF loss
   2. Clinically relevant cataract (likely to require cataract surgery within the next 2 years)
   3. Dementia or other non-glaucomatous neurological disease causing VF loss
   4. Adnexal conditions causing VF loss (including but not limited to blepharochalasis)

8. Diagnosed with cancer in the last 5 years (with exception of non-melanoma skin cancer).

9. Any clinical condition that, in the investigator's opinion would make the participant unsuitable for the trial.

10. Concurrently enrolled in any other interventional trial or participation in previous clinical trial of glaucoma.

11. Current use of, and unwilling to abstain from, over-the-counter additional vitamin B3/NAM oral supplements (including skin preparations such as ointments/emulsions), Ginkgo Biloba and/or Coenzyme Q10 supplements, throughout the duration of their participation in the trial.