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Abstract #19375 Published in IGR 9-3
Ocular carteolol: A review of its use in the management of glaucoma and ocular hypertension
Henness S; Harrison TS; Keating GMDrugs and Aging 2007; 24: 509-528
Ocular carteolol (Mikelan®, Teoptic(registered trademark), Ocupress®) is a nonselective β-adrenoceptor antagonist with intrinsic sympathomimetic activity (ISA). Ocular carteolol effectively reduces intraocular pressure (IOP) in patients with open-angle glaucoma (OAG) or ocular hypertension (OH). Twice-daily administration of standard carteolol has generally similar IOP-lowering efficacy to other ocular β-adrenoceptor antagonists such as timolol, betaxolol and metipranolol in patients with OAG or OH. In addition, long-term treatment with carteolol has similar efficacy to timolol and betaxolol in terms of reducing IOP and maintaining visual fields in patients with newly diagnosed primary OAG (POAG). The new long-acting formulation of once-daily carteolol has equivalent efficacy to the standard formulation of carteolol administered twice daily in patients with OAG or OH. Both the standard and long-acting formulations of ocular carteolol are generally well tolerated in terms of topical adverse effects involving the eyes or systemic adverse effects involving the cardiovascular system. Thus, twice-daily carteolol is a well established option in the treatment of glaucoma and OH, and the new oncedaily formulation of long-acting carteolol offers similar efficacy and tolerability with a potential for improved patient adherence. Pharmacological Properties: Carteolol is a nonselective β-adrenoceptor antagonist with properties unlike those of other β-adrenoceptor antagonists (i.e., ISA and minimal local anaesthetic activity). Ocular carteolol significantly reduced IOP in healthy volunteers. In addition, significant reductions in aqueous humour production were seen with carteolol in patients with POAG; it did not alter corneal sensitivity, tear secretion or pupil diameter. Unlike timolol or betaxolol, carteolol also appeared to improve perfusion of the optic nerve head. Ocular carteolol did not affect respiratory function in healthy volunteers, although bronchoconstriction was seen in patients with asthma. Although carteolol had similar cardiovascular effects to other ocular β-adrenoceptor antagonists in healthy volunteers and patients with asthma, unlike timolol, it did not have a deleterious effect on the lipid profile in patients with POAG or OH. Plasma carteolol concentrations were significantly lower with the long-acting formulation of ocular carteolol than with the standard formulation. In animal models, the precorneal residence time of carteolol was increased with the long-acting versus the standard formulation, allowing for prolonged ocular delivery. Moreover, compared with standard carteolol, a single dose of long-acting carteolol resulted in significantly higher carteolol concentrations at certain timepoints in the iris and ciliary body, indicating enhanced ocular penetration. Therapeutic Efficacy: The results of numerous trials showed that the ocular hypotensive efficacy of standard carteolol 1% or 2% twice daily was similar to that of timolol 0.25% or 0.5% twice daily, betaxolol 0.5% twice daily or metipranolol 0.3% twice daily in patients with POAG, OAG or OH after 1-12 months of treatment. However, 3 months of treatment with levobunolol 0.5% twice daily resulted in a significantly greater reduction in IOP than carteolol 2% twice daily in patients with OAG or OH. A significant reduction from baseline in IOP was seen with carteolol in most studies. Long-term treatment (for up to 7 years) with carteolol 1% twice daily had similar efficacy to timolol 0.25% twice daily and betaxolol 0.5% twice daily in terms of reducing IOP and maintaining visual fields in patients with newly diagnosed POAG. Combination therapy with carteolol plus latanoprost reduced IOP to a significantly greater extent than monotherapy with latanoprost or combination therapy with nipradilol plus latanoprost in patients with POAG or normal-tension glaucoma. The ocular hypotensive efficacy of long-acting carteolol administered once daily was equivalent to that of the standard formulation of carteolol administered twice daily in two well designed trials in patients with OAG or OH. In addition, data from a third trial revealed significant reductions from baseline in IOP with both the long-acting and standard formulations of carteolol in patients with PAOG or OH. Tolerability: Ocular administration of standard or long-acting carteolol was generally well tolerated in patients with POAG, OAG or OH. In general, there were no significant differences in the incidence of ocular symptoms (e.g. burning/stinging at instillation, tearing, ocular pain, blurred vision, itching, conjunctival hyperaemia) between patients receiving carteolol and those receiving comparators such as timolol, metipranolol or levobunolol. However, several studies reported better ocular tolerability of carteolol versus timolol for certain endpoints (e.g., fewer ocular symptoms overall and less burning and eye pain). The long-acting formulation of carteolol was associated with a low incidence of blurred vision ((less-than or equal to)2% of patients). Few differences emerged between carteolol and other β-adrenoceptor antagonists in terms of cardiovascular effects (i.e., effects on heart rate and blood pressure) in patients with POAG, OAG or OH. However, one study found a significantly lower incidence of cardiovascular adverse events overall and a significantly lower incidence of bradycardia with carteolol than with timolol; in particular, carteolol seemed less likely to induce nocturnal bradycardia.
Dr. G.M. Keating, Wolters Kluwer Health Adis, 41 Centorian Drive, North Shore 0754, Auckland, New Zealand. demail@adis.co.nz
Classification:
11.3.4 Betablocker (Part of: 11 Medical treatment > 11.3 Adrenergic drugs)