Plasma levels and systemic safety of 0.1% unpreserved Timolol maleate gel, 0.5% Timolol aqueous solution and 0.5% Timolol maleate gel

Analysis of topical dosing and administration effects on ocular drug delivery in a human eyeball model using computational fluid dynamics

Predicting the spatial and temporal drug concentration distributions in the eyes is essential for quantitative analysis of the therapeutic effect and overdose issue via different topical administration strategies. To address such needs, an experimentally validated computational fluid dynamics (CFD) based virtual human eye model with physiologically realistic multiple ophthalmic compartments was developed to study the effect of administration frequency and interval on drug concentration distributions. Timolol was selected as the topical dosing drug for the numerical investigation of how administration strategy can influence drug transport and concentration distribution over time in the human eye. Administration frequencies employed in this study are 1-4 times per day, and the administration time intervals are Δt = 900 s, 1800 s, and 3600 s. Numerical results indicate that the administration frequency can significantly affect the temporal timolol concentration distributions in the ophthalmic compartments. More administrations per day can prolong the mediations at relatively high levels in all compartments. CFD simulation results also show that shorter administration intervals can help the medication maintain a relatively higher concentration during the initial hours. Longer administration intervals can provide a more stable medication concentration during the entire dosing time. Furthermore, numerical parametric analysis in this study indicates that the elimination rate in the aqueous humor plays a dominant role in affecting the drug concentrations in multiple ophthalmic compartments. However, it still needs additional clinical data to identify how much drugs can be transported into the cardiac and/or respiratory systems via blood circulation for side effect assessment.

Psoriasis precipitated by timolol eye drops. A series of eight cases

Induction of psoriasis following administration of beta blocker containing eye drops has rarely been documented. We report eight cases of psoriasis triggered by timolol eye drops. Since the clinical and histopathological features of this drug reaction are indistinguishable from those of idiopathic psoriasis, a thorough drug history should be taken in all patients, especially elderly ones, with recent onset of psoriasis.

Timolol 0.1% in Glaucomatous Patients: Efficacy, Tolerance, and Quality of Life

Glaucoma is a progressive, chronic optic neuropathy characterized by a typical visual field defects. Four main classes of topical medication are actually available on the market: beta-blockers, prostaglandins, alpha2-agonists, and topical carbonic anhydrase inhibitor to treat intraocular pressure (IOP). The aim of this review is to outline the efficacy of timolol and to evaluate the impact of this treatment on patients' quality of life. Among beta-blockers, timolol is most used at three different concentrations: 0.1%, 0.25%, and 0.5%. While the first one is a gel, the other two products are solution. Timolol has few topical side effects, while it has some important systemic side effects on the cardiac and respiratory systems. The balance between efficacy and safety is always the main aspect to care patients. Because of the less efficacy of timolol 0.1% solution, the possibility to use carbomers as vehicle in the gel drops helped timolol 0.1 to be used in clinics, extending the time contact between the active ingredient and the surface of the cornea. Using preservative-free timolol 0.1 for treatment, IOP was at the same level of the other beta-blockers at higher concentration, but it was better tolerated. Preservative-free treatment improved the quality of life reducing dry-eye like symptoms; furthermore, the presence of an artificial tear in the medication bottle could help adherence. The once daily dosing improves compliance.

Efficacy and safety of preservative-free timolol 0.1% gel in open-angle glaucoma and ocular hypertension in treatment-naïve patients and patients intolerant to other hypotensive medications

GOALS

To assess the efficacy and safety of preservative-free timolol 0.1% gel in patients with primary open-angle glaucoma (POAG) and ocular hypertension (OHT).

METHODS

In this multicenter, open-label, non-controlled clinical trial in Algeria, treatment-naïve patients with intraocular pressure (IOP)>20mmHg and<31mmHg (treatment-naïve patients, group 1) and patients with IOP controlled by current ocular monotherapy but presenting with local intolerance in at least one eye (intolerant patients; group 2) were eligible. Timolol gel was administered once daily in the morning for 84 days. The primary efficacy criteria were reduction in IOP (group 1) and maintenance of baseline IOP (group 2).

RESULTS

Overall, 93 patients were included (53 in group 1, 40 in group 2). All patients in group 2 had been previously treated with preserved eye drops. In group 1, patients showed a significant reduction in IOP with mean changes in the worse eye of -10.3±3.0mmHg at D28 and -10.8±2.5mmHg at D84 (P<0.0001). In group 2, the maintenance of efficacy on IOP at D84 was satisfactory in 91.7% of patients (worse eye). Preservative-free timolol gel was well tolerated in both groups. In group 2, the overall symptom score was significantly reduced from 8.6±5.1 to 0.9±1.6 at D28 and 0.7±1.2 at D84 (P<0.0001), and the overall ocular sign score from 3.7±2.1 to 0.8±1.0 at D28 and 0.6±0.8 at D84 (P<0.0001).

CONCLUSIONS

This preservative-free timolol 0.1% gel was effective in decreasing IOP in treatment-naïve patients and in controlling IOP and reducing ocular signs and symptoms in patients intolerant to their previous preserved medications.