A clinical trial of MK-507, Trusopt, for raised intraocular pressure--the Australian experience.
BACKGROUND
Since the introduction of carbonic anhydrase inhibitors, a topical preparation has been sought to avoid the complications of systemic medication while retaining the effect of lowering intraocular pressure. Recently, a topical carbonic anhydrase inhibitor, MK-507, has been found superior to others and introduced for multicentre clinical trial.


METHODS
As part of an international multicentre trial, we compared MK-507 with beta blockers for one year in 20 patients with raised intraocular pressure, both as monotherapy and in combination.


RESULTS
Twelve patients with a mean peak pressure of 31.9 +/- 6.8 mmHg (range, 22 to 49 mmHg) off all medication received MK-507. After two weeks, mean peak pressure was 24.7 +/- 6.1 mmHg (range, 14 to 41 mmHg)--a 22.6% fall in pressure. Six of these patients had a mean peak pressure of 27.8 +/- 6.4 mmHg (range, 21 to 41 mmHg), a fall of 19.2% from day one and were given timolol as add-on therapy. This resulted in a fall to 19.1 +/- 2.8 (range, 15 to 24 mmHg) at year one, a fall of 31.3% after add-on. Four patients on timolol and four on betaxolol gave similar falls in pressure with an additional fall when MK-507 was used as add-on therapy.


CONCLUSIONS
MK-507 demonstrated its effectiveness as an ocular hypotensive agent in this trial of patients with an unusually high rise in pressure. It showed a hypotensive effect roughly equivalent to beta blockers. It is likely that either a topical carbonic anhydrase inhibitor or a cardioselective beta blocker will be the medication of first choice in newly diagnosed glaucoma.
Gillies
W E
WE
Clinic 3, Royal Victorian Eye and Ear Hospital, East Melbourne, Victoria.
Brooks
A M
AM
D000287:Administration, Topical; D000319:Adrenergic beta-Antagonists / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001315:Australia; D015784:Betaxolol / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use; D002257:Carbonic Anhydrase Inhibitors / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D004311:Double-Blind Method; D004359:Drug Therapy, Combination; D005260:Female; D005500:Follow-Up Studies; D005901:Glaucoma / Q000188:drug therapy* / Q000503:physiopathology; D006801:Humans; D007429:Intraocular Pressure / Q000187:drug effects*; D008297:Male; D008875:Middle Aged; D009798:Ocular Hypertension / Q000188:drug therapy* / Q000503:physiopathology; D009883:Ophthalmic Solutions; D012449:Safety; D013449:Sulfonamides / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D013876:Thiophenes / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D013999:Timolol / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use; D016896:Treatment Outcome
D000319:Adrenergic beta-Antagonists; D002257:Carbonic Anhydrase Inhibitors; D009883:Ophthalmic Solutions; D013449:Sulfonamides; D013876:Thiophenes; D013999:Timolol; C062765:dorzolamide; D015784:Betaxolol