Pharmacokinetic parameters estimated for dorzolamide and brinzolamide after single topical ocular administration of Trusopt (dorzolamide hydrochloride solution, 2%) and Azopt (brinzolamide suspension, 1%) to pigmented rabbit
Parameters were estimated using noncompartmental analysis (WinNonlin, version 1.5; Pharsight, Inc.). For brinzolamide, no drug levels were detected in the posterior vitreous.
| Tissue | Dorzolamide | Brinzolamide | ||||||
|---|---|---|---|---|---|---|---|---|
| Cmax | Tmax | T1/2 | AUC0–24 | Cmax | Tmax | T1/2 | AUC0–24 | |
| μg/g | h | h | μg h/ml or g | μg/g | h | h | μg h/ml or g | |
| Cornea | 36.61 | 0.25 | 1.08 | 51.21 | 19.27 | 0.50 | 1.71 | 50.88 |
| Conjunctiva | 68.74 | 0.25 | 0.720 | 49.55 | 28.80 | 0.25 | 1.01 | 37.94 |
| Aqueous humor | 1.92 | 0.50 | 7.06 | 6.159 | 0.97 | 0.75 | 6.16 | 3.14 |
| Sclera (anterior) | 47.18 | 0.50 | 0.559 | 36.13 | 8.17 | 0.25 | 0.929 | 5.22 |
| Sclera (posterior) | 4.92 | 0.25 | 1.09 | 3.46 | 2.70 | 0.25 | 0.134 | 1.34 |
| Retina (anterior) | 3.68 | 0.50 | 0.87 | 3.46 | 0.82 | 1.0 | 3.94 | 2.42 |
| Retina (posterior) | 0.091 | 0.50 | 1.23 | 0.095 | 0.059 | 0.50 | 0.812 | 0.051 |
| Vitreous (anterior) | 0.07 | 0.75 | 1.99 | 0.208 | 0.034 | 1.0 | 8.07 | 0.185 |
| Vitreous (posterior) | 0.0096 | 1.0 | 1.23 | 0.018 | – | – | – | – |
| Optic nerve | 1.08 | 0.50 | 2.77 | 6.16 | 0.28 | 0.75 | 3.52 | 0.66 |
Cmax, the maximum observed drug concentration in a particular tissue; Tmax, the time at which Cmax occurs; T1/2, the half-life of the drug in tissue; AUC0–24, the area under the curve obtained by plotting the concentration-time data, where t is the last time point at which drug concentration was measured.
–, Pharmacokinetic parameters are not available due to undetected drug levels.