Biomedical subjects

W C Stewart

Publications and source records attributed to W C Stewart.

At least 37 records · Page 2Linked to original sources

PubMed2000

Brimonidine 0.2% versus dorzolamide 2% each given three times daily to reduce intraocular pressure.

PURPOSE: To evaluate the efficacy and safety of brimonidine compared with dorzolamide given three times daily as monotherapy in patients with primary open-angle glaucoma or ocular hypertension. METHODS: In a double-masked, multicenter, crossover comparison in 40 patients, qualified patients were washed out from their previous medication and randomized to dorzolamide 2% or brimonidine 0.2% for the first 6-week treatment period. Patients then were washed out for 2 weeks and started on the opposite medication for the second 6-week period. RESULTS: Baseline intraocular pressure for all 40 subjects (76 eyes) was 24.1 +/- 2.0 mm Hg. This study found that the 8:00 AM trough intraocular pressure after 6 weeks of therapy for dorzolamide was 20. 7 +/- 3.1 mm Hg and for brimonidine 20.8 +/- 3.2 mm Hg (P =.99). The peak intraocular pressure (2 hours after dosing) for dorzolamide was 18.6 +/- 3.4 mm Hg and for brimonidine 17.8 +/- 2.7 mm Hg (P =.10 ). Dorzolamide caused more stinging upon instillation (P <.01) and brimonidine more itching (P =.01). No statistical differences existed between groups for systemic adverse events. Six patients, all on brimonidine, were discontinued from a treatment period early. Of these, two were discontinued for inadequate pressure control, two with dizziness and fatigue, one with ocular pain, and one for lifestyle reasons (P =.07). CONCLUSIONS: This study found similar efficacy and safety between monotherapy treatment with dorzolamide or brimonidine when each was given three times daily to patients with ocular hypertension or primary open-angle glaucoma.

Adrenergic alpha-Agonists↗

PubMed2000

Factors associated with long-term progression or stability in primary open-angle glaucoma.

PURPOSE: To evaluate long-term risk factors for progression or stability in patients with primary open-angle glaucoma. METHOD: We retrospectively included consecutively reviewed patients who had primary open-angle glaucoma for at least 5 years in this multicenter trial. Historical and clinical factors in these patients were evaluated for their association with stability or progression of the glaucoma. RESULTS: We included 218 patients in this study; of these, 34 progressed over an average length of follow-up of 45.5 +/- 30.0 months, and 184 were stable over an average of 72.8 +/- 18.3 months. The mean intraocular pressure over the follow-up period for the progressed group was 19.5 +/- 3.8 mm Hg and for the stable group 17. 2 +/- 3.1 mm Hg (P =.001). The average standard deviation of individual intraocular pressures was greater in the progressed group (5.1 mm Hg) than the stable group (3.9 mm Hg, P =.012). Baseline characteristics indicating a greater potential to progress were a larger cup-to-disk ratio (P <.001), a greater number of medications (P =.02), older age (P.007), and worse visual acuity (P =.003). However, no difference was observed in pressure levels that prevented progression in these subpopulations compared with the total sample size. CONCLUSIONS: This study suggests that lowering the intraocular pressure is important in the treatment of primary open-angle glaucoma to help prevent long-term progression. Lowering the pressure, however, is not uniformly effective in preventing progression. Additionally, risk factors for progression do not further help identify pressure levels that prevent worsening of glaucoma.

Aged↗

PubMed2000

Differences in ocular surface irritation between timolol hemihydrate and timolol maleate.

PURPOSE: We evaluated the anterior segment surface reaction findings between timolol hemihydrate and timolol maleate. The only known difference between these preparations is the maleate salt. METHODS: After a baseline examination, we randomized 28 healthy subjects (26 completed) to timolol hemihydrate or timolol maleate given in both eyes twice daily, in a double masked fashion, for 1 week. Subjects then were evaluated at the morning trough (hour 0 examination), dosed, and re-evaluated in 1 hour (hour 1 examination). Subjects were left untreated for 1 week and then switched to the opposite medication for the second study period. RESULTS: Corneal staining (graded 0 to 4) for timolol maleate was worse between baseline (0.9) and hour 0 (1.4; P =.009) and baseline and hour 1 (1.4; P =.011). Also, mean punctate corneal staining for timolol maleate was increased from baseline (22.6) to hour 0 (31.7; P =.033) and showed borderline significance to hour 1 (33.4; P =.058), and for timolol hemihydrate there was a borderline significant elevation from baseline (24.2) to hour 1 (29.8; P =.060). When treatment groups were compared, there was a greater change in corneal staining with timolol maleate than timolol hemihydrate from baseline to hour 0 (P =.020) and greater staining with timolol maleate than timolol hemihydrate at hour 0 (P =.032). Nasal conjunctiva showed increased mean staining with timolol maleate from baseline (23.6, P =.035) to hour 0 (29.5, P =.035) and to hour 1 (31.9 P =.038) but not with timolol hemihydrate. There were increased symptoms of ocular dryness from baseline to hour 0 with timolol maleate (P =.012) but not with timolol hemihydrate. CONCLUSIONS: The study suggests that timolol maleate potentially may have more of an irritant effect than timolol hemihydrate on the corneal and nasal conjunctival epithelium.

Adrenergic beta-Antagonists↗

PubMed2000

Emerging perspectives on glaucoma: highlights of a roundtable discussion.

PURPOSE: To present emerging perspectives on open-angle glaucoma related to patient compliance, current drug therapy, and treatment options. METHODS: Roundtable discussion. RESULTS: The panel discussion identified the following issues about patient compliance:1. It is a common problem in clinical practice and is often underappreciated by physicians.2. It is difficult for clinicians to detect.3. There are several risk factors that increase the probability of noncompliance. 4. Compliance can be improved through education, communication, improvement of the doctor-patient relationship, compliance aids, and simplifying the treatment regimen. CONCLUSION: Patients' compliance with the therapeutic regimen for open-angle glaucoma is very important to the eventual outcome of their disease treatment. Physicians can improve their patients' compliance by a few simple, cost-effective interventions in the clinical setting. When considering different agents as first-line therapies, once-a-day dosing would be optimal for enhancing compliance.

Communication↗

PubMed2000

Twenty-four hour control of intraocular pressure with dorzolamide and timolol maleate in exfoliation and primary open-angle glaucoma.

PURPOSE: To determine the efficacy and safety of adding dorzolamide 2% twice daily to timolol maleate solution 0.5% twice daily when treating exfoliation glaucoma or primary open-angle glaucoma. METHODS: This was a single-centre, crossover intra-individually controlled comparison. Sixty-two consecutive patients (31 with exfoliation glaucoma and 31 with primary open angle glaucoma) chronically treated with timolol maleate twice daily were included in this trial. Patients then had added dorzolamide 2% twice daily (08:00 and 20:00), instilled approximately 10 min after timolol maleate. Patients underwent diurnal intraocular pressure (IOP) testing (six measurements over 24 h), first on timolol maleate monotherapy and 2 months later following the addition of dorzolamide 2% as adjunctive therapy. RESULTS: On timolol monotherapy patients with exfoliation glaucoma had a higher mean IOP at 02:00, 06:00, 10:00, 14:00 and 22:00 hour time points as well as a higher maximum, minimum and range of IOP throughout the day compared with the primary open-angle glaucoma group (p < 0.05). Following the addition of dorzolamide as adjunctive therapy to timolol maleate there was a significant reduction in IOP (p < 0.05) at all time points in both glaucomas, but mean IOP at 10:00, 14:00, 18:00 and 22:00 hour time points, as well as the peak and range of IOP, remained higher in the exfoliation glaucoma group. No serious adverse events were noted with dorzolamide. Bitter taste, the most common symptom, was noted in 30% of patients. CONCLUSIONS: These data suggest that dorzolamide 2% used adjunctively with timolol maleate 0.5% solution is effective in reducing diurnal IOP in patients with primary open-angle and exfoliation glaucoma but does not alter the characteristics of higher IOP levels in the latter disease.

Adrenergic beta-Antagonists↗

PubMed2000

Comparison of the efficacy and safety of latanoprost 0.005% compared to brimonidine 0.2% or dorzolamide 2% when added to a topical beta-adrenergic blocker in patients with primary open-angle glaucoma or ocular hypertension.

The purpose of this study was to evaluate the ocular hypotensive efficacy and safety of latanoprost 0.005% (Xalatan, Pharmacia & Upjohn), brimonidine (Alphagan, Allergan), and dorzolamide (Trusopt, Merck Inc.) when added to a beta-blocker in patients with ocular hypertension or primary open-angle glaucoma. This was a multicenter, retrospective analysis which included all reviewed patient records in which latanoprost, brimonidine or dorzolamide were added to a beta-blocker for at least three months. Patients who were treated for less than three months, who failed therapy due to ineffectiveness of the medicine or an adverse event also were included. The study included 141 patients. Latanoprost (n = 50) showed an intraocular pressure of 16.7 +/- 3.3 mm Hg (-6.3 +/- 4.1 mm Hg, P < 0.001), brimonidine (n = 24) 17.4 +/- 4.9 mm Hg (-4.2 +/- 4.5 mm Hg, P < 0.001), and dorzolamide (n = 67) 20.1 +/- 6.1 mm Hg (-3.1 +/- 5.1 mm Hg, P < 0.001) at three months. A significant difference was observed in the absolute level of intraocular pressure (P < 0.005) and the change from baseline between groups (P < 0.005) at three months. A significant difference was observed between groups in the success rate of therapy between latanoprost (70%), brimonidine (58%) and dorzolamide (40%) (P = 0.008). No significant differences were observed between groups for rate or type of adverse events leading to discontinued therapy. This study showed that latanoprost, when added to beta-blockers, compares favorably in ocular hypotensive efficacy and is similar in safety to brimonidine and dorzolamide.

Administration, Topical↗

PubMed2000

Therapeutic success of latanoprost 0.005% compared to brimonidine 0.2% in patients with open-angle glaucoma or ocular hypertension.

The purpose of this study was to evaluate the success rate ofmonotherapy with latanoprost 0.005% once daily versus brimonidine 0.2% twice daily in patients with open-angle glaucoma or ocular hypertension. Patients who were prescribed latanoprost or brimonidine as monotherapy were included in this study, and their consecutive charts were retrospectively reviewed. The primary efficacy variable was success of therapy, defined as a reduction in intraocular pressure > or =3 mm Hg without an adverse event leading to discontinuation over a potential of six months of therapy. We included 157 patients in this study. In the latanoprost group, 64 of 92 (70%) were considered successes; 26 of 65 (40%) were successful with brimonidine (P < 0.001). Nine failed brimonidine therapy, and one latanoprost, because of an adverse event, and the rest failed because of inadequate intraocular pressure response. The change from baseline in intraocular pressure was significantly greater with latanoprost (mean +/- S.D., 21.6 +/- 5.1 to 17.1 +/- 3.3 mm Hg) than brimonidine (23.7 +/- 5.6 to 21.9 +/- 5.7 mm Hg) (P = 0.001). Overall, 52 (80%) brimonidine- and 41 (45%) latanoprost-treated patients required additional visit(s) to adjust therapy to further lower intraocular pressure or to assess an adverse event (P < 0.001). In conclusion, latanoprost more likely provides a successful response to therapy than brimonidine when used as monotherapy in primary open-angle glaucoma or ocular hypertensive patients.

Adrenergic alpha-Agonists↗

PubMed1999

Regulation of signal transducers and activators of transcription (STATs) by effectors of adipogenesis: coordinate regulation of STATs 1, 5A, and 5B with peroxisome proliferator-activated receptor-gamma and C/AAAT enhancer binding protein-alpha.

We have recently demonstrated that three signal transducers and activators of transcription (STAT) family members are induced during adipocyte differentiation (Stephens et al., J. Biol. Chem. 271 (1996) 10441-10444). Since STATs 1, 5A, and 5B are induced during adipocyte differentiation, we have examined the ability of these proteins to be regulated by components of the differentiation cocktail. In addition, we have examined the effects of potent effectors of differentiation on STAT protein expression during adipogenesis. A negative effector, tumor necrosis factor-alpha (TNFalpha), and a positive effector, a thiazolidinedione, were used in these experiments. Our results demonstrate that the expression of STATs 1, 5A, and 5B is not dramatically influenced by individual components of the differentiation cocktail. However, the expression of these three STAT family members tightly correlates with lipid accumulation. Moreover, the expression of STATs 1, 5A, and 5B, but not STATs 3 and 6, are regulated in an identical fashion to both C/AAAT enhancer binding proteins alpha and peroxisome proliferator-activated receptor-gamma by TNFalpha and a thiazolidinedione. Furthermore, the expression of adipocyte-expressed JAK kinases are unaffected by effectors of differentiation. These findings suggest that three STAT family members may play a role in the regulation of adipocyte gene expression.

3T3 Cells↗

PubMed1999

Effects of carteolol and timolol on plasma lipid profiles in older women with ocular hypertension or primary open-angle glaucoma.

PURPOSE: To determine the effect on serum lipid levels of carteolol hydrochloride 1.0% or timolol maleate 0.5% given twice a day to women age 60 years and older with primary open-angle glaucoma or ocular hypertension. METHOD: We included 112 patients in this double-masked, randomized, multicenter trial. Fasting clinical laboratory studies were evaluated at baseline and at 12 weeks. Patients were instructed not to change their dietary, alcohol consumption, or exercise habits during the study. RESULTS: For the carteolol group, the high-density lipoprotein (HDL) and total cholesterol/high-density lipoprotein (TC/HDL) ratio at baseline of 50.1 +/- 1.5 mg/dl and 4.7 +/- 0.2 changed by the 12-week visit to 51.3 +/- 1.9 mg/dl (P = .25) and 4.6 +/- .02 (P = .47), respectively. For the timolol maleate group, the baseline HDL and TC/HDL ratio of 53.6 +/- 2.2 mg/dl and 4.4 +/- 0.2 changed to 50.2 +/- 1.9 mg/dl (P < .001) and 4.7 +/- 0.2 (P = .001), respectively, at the 12-week visit. Carteolol patients showed no significant change from baseline, whereas the HDL (P < .001) and TC/HDL ratio decreased (P = .001) significantly in the timolol maleate group. There also was a significant difference in the change from baseline at 12 weeks between carteolol and timolol maleate groups for the HDL and TC/HDL ratio (P = .01 and .012, respectively). No differences in TC, low-density lipoprotein (LDL), or triglycerides (TG) or in changes from baseline were observed between groups at 12 weeks (P > .05). At 12 weeks, no differences were observed between carteolol and timolol maleate groups in intraocular pressure or safety (P > .05), except that patients given carteolol demonstrated fewer solicited ocular symptoms (P = .007). CONCLUSIONS: Carteolol appears to be neutral in its effect on serum lipid levels, whereas timolol maleate adversely affects the HDL and TC/HDL ratio in women age 60 years and older with ocular hypertension or primary open-angle glaucoma.

Adrenergic beta-Antagonists↗

PubMed1999

Comparison of 24-hour intraocular pressure reduction with two dosing regimens of latanoprost and timolol maleate in patients with primary open-angle glaucoma.

PURPOSE: To compare the 24-hour diurnal ocular hypotensive efficacy of two dosing regimens of latanoprost, once daily (8 AM or 10 PM), vs timolol maleate, twice daily. METHODS: We measured six diurnal intraocular pressure curves (6 AM, 10 AM, 2 PM, 6 PM, 10 PM, and 2 AM) in one randomly selected eye of 34 Greek patients newly diagnosed with primary open-angle glaucoma. The first diurnal curve was an untreated baseline. Patients began taking timolol 0.5%, twice daily, for 2 months. Patients were randomly assigned to latanoprost 0.005% given at 8 AM or 10 PM for 1 month and then changed to the other dosing regimen for 1 month. A diurnal curve was performed after each dosing period. RESULTS: The baseline diurnal pressure for all 34 subjects was 23.1 +/- 3.7 mm Hg. The average intraocular pressures at 6 AM for patients who were given latanoprost in the evening (17.9 +/- 2.9 mm Hg) was statistically lower than that in patients given timolol solution (20.1 +/- 2.5 mm Hg, P = .003); however, patients who were given timolol demonstrated a similar diurnal intraocular pressure (19.1 +/- 2.8 mm Hg) to both morning (18.8 +/- 3.7 mm Hg) and evening doses (18.8 +/- 3.6 mm Hg) of latanoprost (P =.329). When the two latanoprost dosages were compared directly, evening administration provided a statistically lower intraocular pressure at 10 AM (P = .0001) and morning administration at 10 PM (P = .0001). This study had an 80% power to exclude a 1.2-mm Hg difference between groups. CONCLUSIONS: This study indicates that in a small population, both latanoprost and timolol are effective in lowering intraocular pressure throughout a 24-hour period; however, latanoprost is most effective in the 12-hour to 24-hour period after administration.

Adrenergic beta-Antagonists↗

PubMed1999

Efficacy and safety of timolol solution once daily vs timolol gel added to latanoprost.

PURPOSE: To compare the efficacy and safety of timolol hemihydrate 0.5% (Betimol, Ciba Vision Ophthalmics, Duluth, Georgia) vs timolol maleate gel-forming solution 0.5% (Timoptic-XE, Merck, Blue Bell, Pennsylvania), both given every morning added to latanoprost 0.005% given every evening. METHODS: A multicenter, randomized, crossover comparison was performed in patients with primary open-angle glaucoma or ocular hypertension. After at least a 4-week run-in period with latanoprost 0.005% (Xalatan, Pharmacia & Upjohn, Kalamazoo, Michigan), both eyes from 30 patients (60 eyes) were randomly assigned to one of the two adjunctive therapies, timolol hemihydrate or timolol maleate gel for 6 weeks. At the end of the first period, the study medicine was discontinued for a 2-week washout period. Patients then received the opposite medication for the second 6-week period. This study had an 80% power to exclude a 1-mm Hg difference between groups. RESULTS: The baseline intraocular pressure after 1 month of latanoprost treatment only for all 30 subjects was 20.8 +/- 2.6 mm Hg. After 6 weeks of timolol hemihydrate, the 24-hour trough intraocular pressure was 17.5 +/- 3.4 mm Hg, and for timolol maleate gel, 17.9 +/- 3.5 mm Hg (P = .74). The peak level 2 hours after dosing for timolol hemihydate was 16.4 +/- 2.6 mm Hg, and for timolol maleate gel, 16.8 +/- 3.8 mm Hg (P = .84). No patient was discontinued from the study because of lack of efficacy. No differences were observed between treatments in visual acuity, anterior segment findings, or adverse events. CONCLUSIONS: Once-daily beta-blocker therapy is an effective ocular hypotensive adjunctive treatment 24 hours after dosing when added to latanoprost, for which timolol hemihydrate 0.5% solution and timolol maleate gel 0.5% appear equally effective and safe.

Adolescent↗

PubMed1999

The use of latanoprost 0.005% once daily to simplify medical therapy in patients with primary open-angle glaucoma or ocular hypertension.

PURPOSE: To evaluate the use of latanoprost 0.005% given once daily to simplify a patient's glaucoma medical regimen. METHODS: We reviewed 527 charts of which we included 61 patients (61 eyes) with either ocular hypertension or primary open-angle glaucoma who were prescribed latanoprost for the purpose of simplifying their glaucoma medical regimen. The successful substitution of latanoprost was defined as a reduction in the number of dosages given daily with the maintenance of intraocular pressure for at least three months no higher than 2 mmHg from the previous medical regimen. RESULTS: This study showed that 43 of 61 patients (70.4%) had latanoprost substituted allowing for fewer dosages per day. Following the substitution the intraocular pressure in the success group fell from 22.5+/-5.9 mmHg to 18.3+/-3.8 mmHg (p<0.001) over an average follow-up of 6.6+/-1.9 months. The total number of dosages per day in the success group fell from 4.8+/-2.4 to 1.7+/-1.3 at exit (p<0.001). Twenty-two patients had one medicine, 14 patients two, and seven patients three medicines discontinued after latanoprost was added. Reasons for failure after the substitution were ineffectiveness of latanoprost (n=11) or an adverse event (n=7). No trends in the number or types of medicines at baseline discontinued were observed in the success or failure groups. CONCLUSION: This study shows that latanoprost 0.005% once daily can be substituted for one or more medicines in the majority of ocular hypertension and primary open-angle glaucoma patients to simplify the medical regimen.

Aged↗

PubMed1999

Comparison of 24 hour control with Timoptic 0.5% and Timoptic-XE 0.5% in exfoliation and primary open-angle glaucoma.

PURPOSE: To compare the 24 hour intraocular pressure (IOP) curve in exfoliation glaucoma (EXG) and primary open-angle glaucoma (POAG) patients treated first with timolol solution 0.5% (TS) twice daily and then with timolol maleate gel forming solution 0.5% (TXE) once daily. METHODS: We prospectively investigated age-matched, newly diagnosed EXG (n = 25) and POAG (n = 25) patients who were admitted as in-patients for 24 hour phasing first with TS and then TXE. RESULTS: Generally TS and TXE controlled both POAG and EXG patients in a similar fashion. However, a trend to lower pressures was observed in both EXG and POAG patients with TS therapy. At two time points (10:00 and 22:00) in POAG patients, TS (18.4 +/- 3.7 and 17.2 +/- 3.1 mm Hg, respectively) provided lower intraocular pressures than TXE (19.8 +/- 3.5 and 18.9 +/- 3.8 mm Hg, respectively) (p < 0.05). CONCLUSION: Both TS twice daily and TXE once daily control POAG and EXG generally to a similar extent.

Adrenergic beta-Antagonists↗

PubMed1999

Latanoprost 0.005% and anterior segment uveitis.

PURPOSE: To evaluate the association of latanoprost with anterior chamber uveitis in glaucoma patients. METHODS: We retrospectively reviewed 527 charts in latanoprost treated patients with: no prior uveitis (Group 1); prior uveitis but were inactive at the time of the study (Group 2); and active uveitis (Group 3). RESULTS: In Group 1 five (1.0%) of 505 patients developed uveitis after beginning latanoprost. The uveitis was trace to 1+ cell in severity and delayed in onset 99.8+/-73.9 days In Group 2 three of 13 (23.1%) patients developed delayed uveitis (trace to 1+ cell). In Group 3 zero of nine (0%) patients had worsened inflammation and the intraocular pressure remained unchanged (22.8+/-7.8 mmHg to 22.0+/-7.3 mmHg) after beginning latanoprost (p=0.38). CONCLUSION: In patients without a prior history a mild delayed uveitis with latanoprost treatment may develop rarely. In patients with a uveitis history, a mild delayed exacerbation potentially may occur and the intraocular pressure may not be decreased in active uveitis.

Aged↗

PubMed1999

The comparative ocular hypotensive effect of apraclonidine with timolol maleate in exfoliation versus primary open-angle glaucoma patients.

PURPOSE: To compare the effect of adding apraclonidine 0.5% to timolol maleate 0.5% in patients with exfoliation versus primary open-angle glaucoma. Since exfoliation glaucoma is known to demonstrate higher pressures than primary open-angle glaucoma on timolol maleate therapy alone, the authors wished to determine whether apraclonidine equalised the intraocular pressure (IOP) between these two glaucomas when added to timolol maleate. METHODS: We age-matched 30 consecutive exfoliation and 30 primary open-angle glaucoma patients who had an IOP > or = 22 mmHg on timolol maleate alone. Patients underwent IOP diurnal curve testing on timolol maleate twice daily alone and, 2 months later, following the addition of apraclonidine 0.5% three times daily. Statistical analysis of the IOP at each time point was by an unpaired t-test between groups. A paired t-test was used to evaluate the reduction in IOP from baseline within groups after the addition of apraclonidine. RESULTS: On timolol maleate alone, exfoliation patients had a higher mean IOP at 06:00 and 10:00 hours as well as a higher peak, range and standard deviation of the IOP compared with primary open-angle glaucoma patients (p < 0.05). Following the addition of apraclonidine the mean, peak and range of IOP were statistically similar between groups and only the standard deviations remained higher in the exfoliation glaucoma group (p < 0.001). The mean diurnal IOP after apraclonidine was added was 20.5 +/- 7.0 mmHg in the exfoliation glaucoma group and 20.0 +/- 3.4 mmHg in the primary open-angle glaucoma group, which was not significantly different between groups (p = 0.73). CONCLUSIONS: This study suggests that apraclonidine 0.5% used adjunctively with timolol maleate 0.5% solution is associated generally with similar IOP control in exfoliation and primary open-angle glaucoma patients.

Adrenergic alpha-Agonists↗

PubMed1999

Systemic beta-blockade with once daily Betimol or Timoptic-XE.

The purpose of this study was to evaluate the effect of timolol hemihydrate 0.5% (Betimol [THH], Ciba Vision Ophthalmics) and timolol maleate gel forming solution 0.5% (Timoptic-XE , [TXE], Merck, Inc.), when both are dosed once daily on the exercise performance. Maximum exercise heart rate reflects systemic beta-blockade activity. Fourteen healthy subjects were randomized to receive either placebo (HypoTears , Ciba Vision Ophthalmics), THH, or TXE by a Latin square technique in a three period crossover design. Subjects were dosed one drop every morning beginning three days before exercise testing. The interval between each test was one week. Exercise testing was performed two hours after dosing. Maximum exercise heart rate showed no statistical difference between TXE and THH (174 +/- 13.1 vs. 172 +/- 14.9 beats/min, respectively, P = 0.72). Both active treatments, however, decreased heart rate compared to placebo (185 +/- 7.3 beats/min, P = 0.017). Time to exhaustion showed no difference between groups (P > 0.10). The double product (product of heart rate and systolic blood pressure) did not show a difference between TXE and THH (P = 0.38) but was reduced compared to placebo (P = 0.0053). One subject on TXE was discontinued from the study after the first exercise test because of secondary heart block during the recovery period. It was concluded that TXE and timolol hemihydrate solution show similar systemic beta-blockade activity when both are dosed once a day.

Adrenergic beta-Antagonists↗

PubMed1999

The use of latanoprost 0.005% once daily and its effect on intraocular pressure as primary or adjunctive therapy.

The purpose of this study was to evaluate differences in efficacy and safety of latanoprost as monotherapy compared to adjunctive therapy in primary open-angle glaucoma. We reviewed records of 527 patients who were treated with latanoprost as mono- or adjunctive therapy to reduce the intraocular pressure. Each patient was treated at least three months unless they were discontinued due to an adverse event or lack of efficacy. In the monotherapy group (n=49) baseline intraocular pressure of 23.6+/-5.2 mm Hg fell to 18.4+/-4.3 mm Hg after 4.4+/-2.0 months of follow-up; in the adjunctive therapy group (n=39) baseline intraocular pressure of 21.8+/-5.7 mm Hg fell to 16.7+/-4.6 mm Hg following 4.3+/-1.8 months of therapy which was a similar change from baseline for both groups (P > 0.9). No differences were noted in the class or number of medicines to which latanoprost could be added including: beta-blockers, alpha-agonists and topical carbonic anhydrase inhibitors. The reasons for failure with monotherapy were mostly adverse events (10/15 patients) and with adjunctive therapy lack of efficacy (14/16 patients). Latanoprost is similarly effective as monotherapy and as an adjunctive agent in reducing the intraocular pressure. Latanoprost can be added successfully to a variety of classes of glaucoma medicines used commonly as adjunctive therapy.

Adrenergic alpha-Agonists↗

PubMed1999

Daily cost of newer glaucoma agents.

The purpose of this study was to evaluate the drop characteristics of newer glaucoma medicines compared to timolol solution and timolol gel forming solution (Timoptic-XE, Merck). We evaluated latanoprost 0.005% (2.5 ml bottle), brimonidine 0.2%, apraclonidine 0.5%, dorzolamide 2%, timolol solution 0.5% (5 and 10 ml bottles), and timolol gel forming solution 0.5% (5 ml bottle) in 14 patients with primary open-angle glaucoma or ocular hypertension. Each patient placed 10 drops onto an analytical scale (one drop every 10 seconds) for all ten preparations. Patients then attempted to instill 10 drops of a tear replacement solution into their ocular cul-de-sac. Medication bottles were weighed before and after patients dispensed from the bottle and then after the bottle was emptied. Weights were converted to volume using the density of the medicine. A statistical difference existed between groups for mean drop volume with latanoprost having the smallest drop volume (.0273 +/- .004 ml) (P<0.005). All manufacturers filled correctly or overfilled their bottles with product and had <10% of medicine wasted. Patients instilled 77.9% of the tear solution correctly. When dosed according to labeling, latanoprost had the lowest cost of therapy at $0.87 daily compared to the other newly released medications (range $1.05 to $1.40). Latanoprost was more expensive, however, than timolol maleate solution or gel (range $0.45 to $0.54 per day). Latanoprost therapy is less expensive per day than dorzolamide, brimonidine or apraclonidine, but more expensive than timolol maleate. Cost per day could be further reduced by limiting medicine wastage upon instillation, however.

Brimonidine Tartrate↗