Efficacy of bunazosin hydrochloride 0.01% as adjunctive therapy of latanoprost or timolol.
OBJECTIVE
To evaluate the ocular hypotensive response of bunazosin hydrochloride 0.01% administered as adjunctive therapy in patients with glaucoma who were already receiving latanoprost 0.005% or timolol 0.5%.


METHODS
Patients with primary open angle glaucoma who had received latanoprost (n = 60) or timolol (n = 60) for 6 months or longer were enrolled and prospectively randomized to receive additional administration of bunazosin or placebo. One hundred twenty eyes of 120 patients were thus divided into 4 subgroups of 30 patients each. Bunazosin was administered twice daily, and timolol or latanoprost was administered per label. The patients were followed up for 3 months. Responders were defined as having a reduction in intraocular pressure of greater than 2 mm Hg from baseline.


RESULTS
Mean baseline intraocular pressure was 22.3 +/- 3.0 mm Hg in the bunazosin subgroup and 22.3 +/- 3.1 mm Hg in the placebo subgroup of the latanoprost arm, and 22.5 +/- 3.5 mm Hg in the bunazosin subgroup and 22.3 +/- 3.0 mm Hg in the placebo subgroup of the timolol arm. In the bunazosin subgroups of both arms, intraocular pressure was significantly reduced compared with baseline measurements (P < 0.05) with mean intraocular pressure measurement reductions of 2.1 +/- 2.4 mm Hg and 2.8 +/- 2.1 mm Hg in the latanoprost arm and 2.6 +/- 2.1 mm Hg and 2.8 +/- 2.1 mm Hg in the timolol arm at 6 and 12 weeks after the start of the follow-up, respectively. In the latanoprost group, bunazosin provided a further reduction of intraocular pressure (7.7%) at 12 weeks from that initially obtained at 2 weeks (P = 0.0377). In the placebo subgroups of the latanoprost and timolol arms, no significant change was found between at baseline and at any visit after the start of the follow-up. In the latanoprost and timolol arms, there was a significant difference in intraocular pressure and its change between the bunazosin subgroup and placebo subgroup at any visit after 4 weeks from the start of the follow-up (P < 0.01).


CONCLUSIONS
Bunazosin hydrochloride 0.01% may provide an additional intraocular pressure reduction in patients already receiving latanoprost or timolol. Since adding bunazosin to eyes treated with latanoprost caused a relatively small hypotensive response at 2 weeks and provided a further reduction from 2 weeks to 12 weeks, longer than 4 weeks may be required to evaluate a clinically meaningful response to treatment. Further investigation on more cases and longer follow-up are needed.
Kobayashi
Hiroshi
H
Department of Ophthalmology, Saga Medical School, Japan. kobayas3@post.saga-med.ac.jp
Kobayashi
Kaori
K
Okinami
Satoshi
S
D000317:Adrenergic alpha-Antagonists / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D000319:Adrenergic beta-Antagonists / Q000009:adverse effects / Q000627:therapeutic use*; D000368:Aged; D004334:Drug Administration Schedule; D004359:Drug Therapy, Combination; D005260:Female; D005902:Glaucoma, Open-Angle / Q000188:drug therapy*; D006801:Humans; D007429:Intraocular Pressure / Q000187:drug effects; D000077338:Latanoprost; D008297:Male; D008875:Middle Aged; D011461:Prostaglandins F, Synthetic / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D011680:Pupil / Q000187:drug effects; D011799:Quinazolines / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D013999:Timolol / Q000009:adverse effects / Q000627:therapeutic use*
D000317:Adrenergic alpha-Antagonists; D000319:Adrenergic beta-Antagonists; D011461:Prostaglandins F, Synthetic; D011799:Quinazolines; D000077338:Latanoprost; D013999:Timolol; C018176:bunazosin