Trends in development and quality assessment of pharmaceutical formulations - F2α analogues in the glaucoma treatment.

The ocular delivery route presents a number of challenges in terms of drug administration and bioavailability. The low bioavailability following topical ophthalmic administration shows that there is a clear need for in-depth research aimed at finding both more efficacious molecules and formulations precisely targeted at the site of action. Continuous technological development will eventually result in improved bioavailability, lower dosages, reduced toxicity, fewer adverse effects, and thus better patient compliance and treatment efficacy. Technological development, as well as increasingly stringent quality requirements, help stimulate analytical progress. This is also clearly evident in the case of medicinal products used in the treatment of glaucoma, which are the subject of this review. Impurity profiling of PGF2α analogues, either in the pure substance or in the finished formulation, is a crucial step in assessing their quality. The development of specific, accurate and precise stability-indicating analytical methods for determining the content and related substances seems to be an important issue in relation to this tasks. A total of 27 official and in-house analytical methods are presented that are used for the analysis of latanoprost, travoprost and bimatoprost. The conditions for chromatographic separation with UV or MS/MS detection and the available results obtained during method validation are described. In addition, several aspects are discussed, with particular emphasis on the instability of the analogues in aqueous solution and the phenomenon of isomerism, which affects a potentially large number of degradation products.

A latanoprost cationic emulsion (STN1013001) vs. other latanoprost formulations (Latanoprost) in open angle glaucoma/ocular hypertension and ocular surface disease: an Italian cost-utility analysis.

BACKGROUND: STN1013001 is an innovative latanoprost cationic emulsion for open-angle glaucoma/ocular hypertension (OAG/OHT) and ocular surface disease (OSD). METHODS AND FINDINGS: A 5-year, 7 health states, 1-year cycle early Markov model-supported cost-utility analysis (CUA) of STN1013001 vs. other latanoprost formulations (Latanoprost) followed the Italian National Health Service (INHS) perspective.One-way, probabilistic and scenario sensitivity analyses tested the uncertainty of the baseline results. Value of information analysis (VOIA) investigated the potential cost-effectiveness of collecting further evidence. RESULTS: Over 5 years, the Markov model-supported CUA predicts STN1013001 to be potentially highly cost-effective vs. Latanoprost (+€57.60 cost at €2020 values; +0.089 Quality-Adjusted Life Years).The Incremental Cost-Utility Ratio (€647.65) falls well below the lower limit of the acceptability range proposed for Italy (€25,000-€40,000).Sensitivity analyses confirmed the robustness of the baseline findings. VOIA highlighted that further information might only be cost-effective for OAG/OHT utilities and OSD-related disutility. CONCLUSION: STN1013001 is potentially highly cost-effective and strongly dominant vs. Latanoprost for OAG/OHT+OSD patients from the INHS perspective. These findings should be re-assessed using the data from the ongoing Phase III trial (NCT04133311) comparing the efficacy and safety of STN1013001 vs. Latanoprost and with future real-world CUAs upon the availability of STN1013001 on the Italian market.

Safety assessment of subconjunctivally implanted devices containing latanoprost in Dutch-belted rabbits.

PURPOSE: Latanoprost is used for the treatment of an increased intraocular pressure (IOP) to prevent the progression of glaucoma. Since the lack of compliance with topical ocular dosing may compromise efficacy, alternate methods of delivery are being sought. A 9-month study was conducted to assess the safety and tolerability of latanoprost-containing subconjunctivally implanted devices. METHODS: Dutch-belted rabbits were implanted subconjunctivally with up to 5 placebo or drug-loaded devices containing from 50 to 180 µg of latanoprost per device. Study assessment consisted of irritation scoring, clinical signs, ophthalmic exams, IOP, electroretinography (ERG), ocular histology of cohorts at 3 and 9 months postimplantation, and systemic exposure to latanoprost acid. RESULTS: The implants were well tolerated, with minimal-to-mild clinical and microscopic ocular findings attributable to either the placebo or drug-loaded devices. Mild conjunctival congestion persisted through week 13 of the study and tended to correlate with the number of devices and presence of drug. Ophthalmic examinations revealed no effects beyond conjunctival surface hyperemia. No effects on the IOP, corneal thickness, or ERG parameters were observed. The lack of changes in the IOP was expected due to the known lack of the IOP-lowering effects in rabbits from latanoprost. Microscopically, implants at the 3-month necropsy were associated with subconjunctival tissue cavities (containing the implants), fibrous encapsulation, and an infiltrate of lymphocytes and macrophages, sometimes as multinucleate cells, into the subconjunctival implant cavity. The drug-containing implants were often associated with inflammatory cell infiltrates, including heterophils (neutrophils), within the implant subconjunctival cavities and adjacent to the implant sites. At the 9-month necropsy, heterophils were no longer common among the inflammatory cell infiltrates; macrophages and lymphocytes persisted; most of the biodegradable implants were fragmented and disintegrating; and fibrovascular proliferation was present within implant luminal remnants. None of the findings were considered adverse. Systemic exposures were above the limit of quantification (0.1 ng/mL) for up to 96 h in the higher-dose groups, consistent with the initial burst phase of compound release. CONCLUSION: Overall, the study supports the safety of the latanoprost-containing subconjunctival device as a means of extended delivery of the antiglaucoma medication. Latanoprost-containing subconjunctival implants were well tolerated by Dutch-belted rabbits for up to 9 months. Such devices may improve patient compliance and serve as a means of extended delivery of antiglaucoma medications.

The long-term outcomes of four alternative treatment strategies for primary open-angle glaucoma.

PURPOSE: To evaluate the long-term effects and costs of four treatment strategies for primary open-angle glaucoma compared to usual care. METHODS: Cost-effectiveness analyses with a lifelong horizon were made from a societal perspective. Data were generated with a patient-level model based on discrete event simulation. The model structure and parameter estimates were based on literature, particularly clinical studies on the natural course of glaucoma and the effect of treatment. We simulated heterogeneous cohorts of 3000 patients and explored the impact of uncertainty with sensitivity analyses. RESULTS: The incremental cost-effectiveness ratio (ICER) of initial treatment with a prostaglandin analogue compared with a ß-blocker was €12.931 per quality-adjusted life year (QALY) gained. A low initial target pressure (15 mmHg) resulted in 0.115 QALYs gained and €1550 saved compared to a gradual decrease from 21 to 15 mmHg upon progression. Visual field (VF) measurements every 6 rather than 12 months lead to health gains at increased costs (ICER €173,486 per QALY gained), whereas measurements every 24 months lead to health losses at reduced costs (ICER €21,516 per QALY lost). All treatment strategies were dominant over 'withholding treatment'. CONCLUSIONS: From a cost-effectiveness point of view, it seems advantageous to aim for a low intraocular pressure in all glaucoma patients. The feasibility of this strategy should therefore be investigated. Additionally, the cost-effectiveness outcomes of initiating monotherapy with a prostaglandin analogue and reducing the frequency of VF testing may be acceptable.

Balancing efficacy and tolerability of prostaglandin analogues and prostaglandin-timolol fixed combinations in primary open-angle glaucoma.

BACKGROUND: Lowering intraocular pressure (IOP) is currently the only therapeutic approach that preserves visual function in primary open-angle glaucoma. In making treatment decisions for first- and second-line therapy, the clinician needs to provide an appropriate balance of efficacy and tolerability. Prostaglandin analogues (PGAs) are frequently used as first-line monotherapy, because of their efficacy and low risk of systemic side effects. Similarly, PGA-based fixed combinations are frequently used in patients who progress or fail to achieve the target IOP. SCOPE: We have reviewed the literature on the management of primary open-angle glaucoma with PGAs, both as monotherapies and in fixed combinations. FINDINGS: In the clinical trial and meta-analysis data identified, bimatoprost 0.03% seems to be associated with a greater overall ability to lower IOP compared with latanoprost, travoprost or tafluprost, at the cost of a slightly higher incidence of conjunctival hyperaemia. Studies indicate that patients' adherence to treatment is generally better with PGAs than with many other monotherapies. In patients requiring more than one IOP-lowering agent, fixed combination treatments may provide improved adherence and tolerability benefits compared with concomitant use of individual treatments. Bimatoprost/timolol fixed combination appears to be slightly more efficacious than latanoprost/timolol or travoprost/timolol, and tolerability differences between the fixed combinations appear to be slight, probably because the addition of timolol to the PGA component lessens the associated hyperaemia. Surveys on EU physician attitudes appear largely in line with these clinical data. CONCLUSION: An appropriate balance between efficacy and tolerability ensures optimum IOP lowering and reduces the risk of non-adherence. PGAs largely fulfil this need as monotherapies and as components of combinations.

The clinical impact of 2 different strategies for initiating therapy in patients with ocular hypertension.

PURPOSE: To assess the impact of 2 strategies for initiating therapy in ocular hypertension (OH) on drug use, intraocular pressure (IOP), and blindness caused by glaucoma. METHODS: Using a simulation model, initiating therapy with timolol (strategy 1) and with latanoprost (strategy 2) was simulated for a hypothetic cohort of ocular hypertension patients with an initial IOP distribution (data of 1000 patients). Adjustment of therapy within 15 months and a subsequent lifelong follow-up, with an IOP dependent conversion to glaucoma, were modeled. The IOP lowering effect of medication (based on a meta-analysis) was applied by Monte Carlo simulation. Therapy could be maintained or changed, depending on the achieved IOP and side effects. Four drugs (latanoprost, timolol, brimonidine, dorzolamide) were used as monotherapy or in combination. Glaucoma conversion rate was based on literature. RESULTS: Treatment goal was achieved in both strategies in 90% by monotherapy. This was 60% for patients with initial IOP's of 30 mm Hg. The originally prescribed medication was maintained in 66% (1) and in 77% (2). IOP decreased with approximately 34%, from 25.4 mm Hg (mean) to 16.7 mm Hg (1) and to 16.5 mm Hg (2) Blindness per person within 18.7 years of life expectancy was 0.0923 years (1) and 0.0870 years (2), which corresponds to approximately 1 month. The difference between strategies was 2 days spent in blindness per patient. CONCLUSIONS: The difference in clinical effects of the strategies is small. This is largely owing to the key concept of a target pressure, which underlies both strategies.

A randomized, 36-month, post-marketing efficacy and tolerability study in Sweden and Finland of latanoprost versus non-prostaglandin therapy in patients with glaucoma or ocular hypertension.

PURPOSE: To compare the effect of time on therapy, efficacy, tolerability and resource utilization of latanoprost or non-prostaglandin analogues (non-PGs) in patients who required a change in intraocular pressure (IOP)-lowering monotherapy. METHODS: This open-label, multicentre study (Sweden, 19 sites; Finland, seven sites) included adults with glaucoma or ocular hypertension with mean diurnal IOP > or = 21 mmHg on ocular hypotensive monotherapy. Patients were randomized to latanoprost monotherapy or non-PG therapy (commercially available therapy other than a PG) and followed for 36 months. End-points included: time to treatment failure (baseline to visit with a change in/addition to treatment); diurnal IOP (mean of 08.00, 12.00 and 16:00 hr measurements) at months 6, 12, 24 and 36; tolerability; and resource utilization, where analyses used Swedish and Finnish 2006 unit costs. RESULTS: Three hundred and twenty-six patients received >or = 1 dose of latanoprost (n = 162) or non-PGs (n = 164). Median time to treatment failure was longer for latanoprost (36 months) than for non-PGs (12 months; p < 0.001); 51% and 24% of patients remained on randomized therapy after 36 months, respectively (p < 0.001). Decreases in mean diurnal IOP from baseline were significantly greater for latanoprost than for non-PGs at months 6 and 12 (p < 0.01). No serious adverse events were judged to be treatment-related. Mean total 36-month direct costs were similar in patients initiated with latanoprost and non-PGs. CONCLUSION: Patients who failed previous monotherapy remained on therapy longer when switched to latanoprost. Latanoprost's IOP-reducing effect and tolerability were sustained over the long term. Resource utilization and costs were generally similar in those initiating latanoprost or non-PG therapy.

Hyperemia-associated costs of medication changes in glaucoma patients treated initially with prostaglandin analogs.

AIMS: To develop a model to estimate and compare the cost of changing therapy due to hyperemia in glaucoma patients treated initially either with latanoprost, bimatoprost, or travoprost monotherapy. METHODS: Data collected from the HealthCore Integrated Research Database, as part of the Glaucoma Adherence and Persistency Study (GAPS), were used to populate the model. Patients with a documented diagnosis of glaucoma who were newly treated (no ocular hypotensive medication and no glaucoma-related procedure during 6 months before first prescription) with latanoprost, bimatoprost, or travoprost monotherapy were identified. The time horizon for the base-case model was the duration of chart abstraction (mean = 4.1 years); a 3-month model also was developed. Physician-reported rates of hyperemia were obtained from chart reviews of 300 patients. Transition rates reflected events related to reports of hyperemia where a physician-driven change (switch or discontinuation) in therapy was documented. The per-patient direct cost (2008) due to hyperemia-driven change in therapy was calculated as the sum of the cost of the initial prescription plus the cost of the office visit where the patient was evaluated and the decision to change therapy was made. Costs were stratified by whether patients were hyperemia free or discontinued the initial therapy due to hyperemia. RESULTS: From the sample of 13,977 newly treated patients, 8,743 patients were started on a prostaglandin monotherapy only. Of these, 5,726 received latanoprost, 1,633 were treated with bimatoprost, and 1,384 received travoprost index monotherapy. Across all treatment groups, costs among hyperemia-free patients were US$73.67 versus US$140.02 for those who discontinued the initial prostaglandin due to hyperemia. Per-patient costs were lowest in the group treated initially with latanoprost. For the base-case model, with latanoprost as the reference, total per-patient incremental costs due to hyperemia-driven change in therapy were US$5.92 for bimatoprost and US$5.43 for travoprost. Results were not highly sensitive to increases either in the incidence of hyperemia among latanoprost-treated patients or in the cost of latanoprost. CONCLUSIONS: Hyperemia results in increased overall costs in patients treated with latanoprost, bimatoprost, and travoprost. Treatment with latanoprost is associated with lower hyperemia-related costs than treatment with bimatoprost or travoprost.

Brimonidine purite 0.1% versus brinzolamide 1% as adjunctive therapy to latanoprost in patients with glaucoma or ocular hypertension.

OBJECTIVE: To evaluate the efficacy and tolerability of brimonidine purite 0.1% in comparison to brinzolamide 1% when used as adjunctive therapy to latanoprost 0.005% in patients with glaucoma or ocular hypertension. METHODS: Randomized, single-center, investigator-masked, parallel-group clinical study. Patients with IOP >or= 18 mmHg while on once-daily latanoprost were randomized to adjunctive treatment with brimonidine purite TID (n = 20) or brinzolamide TID (n = 20) for 3 months. Intraocular pressure (IOP) was measured at 8 a.m., 10 a.m., and 4 p.m. at latanoprost-treated baseline and after 1 and 3 months of latanoprost and adjunctive therapy. A patient questionnaire was administered to evaluate the tolerability of eye drop instillation. RESULTS: Baseline mean diurnal IOP (+/- standard deviation, mmHg) on latanoprost was comparable between groups (brimonidine purite: 19.6 +/- 2.94; brinzolamide: 19.8 +/- 3.25; p = 0.846). Mean diurnal IOP at Month 3 was 16.3 +/- 2.63 mmHg with brimonidine purite and 17.8 +/- 2.19 mmHg with brinzolamide (p = 0.028). Adjunctive use of brimonidine purite provided greater IOP lowering than brinzolamide at 10 a.m. (p < 0.001) and 4 p.m. (p = 0.050) and equivalent IOP lowering to brinzolamide at 8 a.m. (p = 0.716). Blurred vision at Month 1 and bitter taste at Months 1 and 3 were more common upon instillation of brinzolamide eye drops. CONCLUSION: Brimonidine purite 0.1% provided significantly lower IOP compared with brinzolamide 1% when used as adjunctive therapy to latanoprost. Both adjunctive therapies were well tolerated. Limitations of this study include the use of a single site and the sample size. Additional studies are needed to further evaluate these drugs as adjunctive therapy to prostaglandin analogs.

Monte Carlo simulation of latanoprost induced iris darkening.

The aim of this study was to provide numerical evidence that latanoprost induced iris darkening (LIID) can be caused by changes to the melanin granule size distribution in the anterior segment of the iris. Iridectomies from two patients were used, where both had undergone unilateral treatment with latanoprost and had exhibited LIID. The untreated eye provided the comparative control. Micrographs from the iris samples were analysed to determine the number and size of the mature melanin granules. Monte Carlo (MC) simulation of light propagation in the iris was performed to examine the changes in reflectance and absorption with varying particle size and density. The reflected intensity of light was obtained as a function of wavelength. CIE colour theory was employed in order to estimate a perceived colour from the reflectance data. MC simulations showed that the reflectance was reduced for the LIID irises compared to the control irises for both subjects and for all wavelengths of light. The MC simulated colours were in good agreement with the in vivo photography of the eye colour. Hence, we have demonstrated that increases in melanin granule size causes iris darkening, and can explain LIID.

Assessment of corneal epithelial integrity after acute exposure to ocular hypotensive agents preserved with and without benzalkonium chloride.

The corneal toxicity of 2 intraocular pressure-lowering agents was compared in a rabbit cornea model with New Zealand White rabbits. Corneal epithelial morphology and cell size were assessed by in vivo confocal microscopy. Baseline microscopic examinations were performed on 1 eye of each animal. Two weeks later, the eyes were bathed for 3 min in travoprost 0.004% preserved without benzalkonium chloride (BAK( or latanoprost 0.005% preserved with 0.02% BAK; the eyes were then rinsed with balanced salt solution, and the corneas were again examined by confocal microscopy (n=4/group). A second group of animals was exposed to the medications through a dosing regimen of 1 drop/min (lpar3 drops total) (n=4/group). In eyes treated with travoprost without BAK (3-min bath), superficial epithelial cells were similar to baseline, as indicated by their visible cell borders and bright nuclei. In contrast, the surface cells in eyes treated with latanoprost were significantly smaller and brighter and had less distinct borders. Surface cell size was significantly smaller as compared with baseline size and as compared with rabbits treated with travoprost without BAK for 3 min. Similar effects on corneal epithelial cell morphology were observed with the 1-drop/min dosing regimen. In this rabbit model, travoprost 0.004% preserved without BAK did not cause corneal epithelial toxicity; latanoprost 0.005% induced superficial cell loss, most likely caused by the presence of a relatively high concentration of BAK (0.02%).

Feasibility and efficacy of a mass switch from latanoprost to bimatoprost in glaucoma patients in a prepaid Health Maintenance Organization.

OBJECTIVE: To assess the feasibility of an automatic switch of a large number of patients with glaucoma or suspicion of glaucoma from latanoprost to bimatoprost, and to compare the efficacy of the 2 prostaglandin analogs before and after the switch. DESIGN: Retrospective nonrandomized comparison. PARTICIPANTS: Forty-three thousand four hundred forty-one California patients and 538 patients at one Southern California clinical facility of a nationwide prepaid health maintenance organization (HMO) who were on either prostaglandin between March 2002 and December 2003 (21 months). METHODS: Beginning in April 2002, patients on latanoprost were systemically switched to bimatoprost by the HMO pharmacy service after obtaining approval from the entire ophthalmology staff. PART 1: computerized dispensing records of California patients were retrieved. PART 2: medical records of patients at one clinical facility were reviewed. MAIN OUTCOME MEASURES: Rates of switching or switching back from one prostaglandin to another, intraocular pressure (IOP) control, and intolerability. RESULTS: PART 1: 17847 patients initially received latanoprost. Of them, 84.8% were switched from latanoprost to bimatoprost, and 13.0% were switched back to latanoprost. Twenty-five thousand five hundred ninety-four patients were started on bimatoprost without previous experience with latanoprost. Of them, 8.6% were later switched to latanoprost use instead. Patients who had previous experience with latanoprost had a statistically significantly higher rate of switching back to latanoprost after a period of bimatoprost use when compared with those who had no prior experience with latanoprost (13.0% vs. 8.6%, respectively; P<0.0001). PART 2: 309 patients were switched from latanoprost to bimatoprost. The mean IOP reduction of 0.51+/-2.77 mmHg (95% confidence interval, 0.20-0.82) after the switch was statistically significant (P = 0.001). Forty-one patients (13.3%) had a decrease of >3 mmHg of IOP. The statistical significance of the IOP reduction after the switch remains in the monotherapy group (P = 0.005) but not in the multitherapy group (P = 0.058). Thirty-three patients (10.7%) who were switched from latanoprost to bimatoprost discontinued bimatoprost and resumed latanoprost. CONCLUSION: A systematic pharmacy-level switch from latanoprost to bimatoprost in a nationwide HMO achieved a high switch rate, with little switching back. There was a small but statistically significant reduction in mean IOP after the switch. An appreciable proportion of patients switched had a clinically significant reduction of IOP.

The cost-effectiveness of bimatoprost 0.03% in the treatment of glaucoma in adult patients--a European perspective.

Glaucoma is a condition affecting one or both eyes with raised intraocular pressure (IOP). IOP should be reduced to prevent progression of visual field loss. This study investigates the cost-effectiveness of bimatoprost compared with latanoprost as first-line monotherapies in the treatment of glaucoma in Austria, Finland and France. On the basis of a single multicentre, randomised, investigator-masked controlled trial, a 6- and 12-month cost-effectiveness model was designed following the treatment recommendations from the European Glaucoma Society. Treatment changes due to insufficient IOP reduction and adverse events were included. The cost-effectiveness analysis showed that the need for adjunctive therapy was the major cost driver. On the basis of evidence from the randomised, investigator-masked clinical trial (RCT), the cost-effectiveness analysis found that bimatoprost was a cheaper and a more effective treatment strategy compared with latanoprost. This was true for all three countries and all IOP targets between 13 and 20 mmHg. The cost-effectiveness result may be generalised to a European setting and perspective.

Assessment of chamber angle pigmentation during longterm latanoprost treatment for open-angle glaucoma.

PURPOSE: This study aimed to determine whether the longterm use of latanoprost is associated with an increase in trabecular pigmentation, especially in subjects in whom iris pigmentation has increased. METHODS: We enrolled 50 subjects for whom treatment was to start for ocular hypertension, primary open-angle glaucoma or normal tension glaucoma. All subjects received latanoprost 0.005% daily. Trabecular pigmentation was documented using gonioscopic photography of the inferior quadrant at baseline, every 3 months for the first year and every 6 months for the second and third years. Three glaucoma specialists evaluated the series of gonioscopic photographs for each eye of each subject in a masked fashion. The intraocular pressure (IOP) was also recorded at each visit. RESULTS: A total of 41 subjects (79 eyes) completed 3 years of follow-up, and none showed any increase in the grade of trabecular pigmentation, including 10 subjects (20 eyes) in whom the iridial pigment increased. CONCLUSION: Although latanoprost increased iridial pigmentation in some subjects, we found no evidence of an increase in trabecular pigmentation over the 3 years of follow-up.

Assessing the cost-effectiveness of switching from a beta-blocker to latanoprost in the treatment of ocular hypertension.

Glaucoma is a pathological condition whose most important risk factor is increased intraocular pressure (IOP). The medical treatment of glaucoma essentially consists of compounds that are able to decrease the IOP. The compounds discussed in this review act in a different way, beta-blockers mainly inhibit the production of aqueous humor, whereas latanoprost decreases the resistance in the outflow channels. beta-Blockers are compounds with a well-known efficacy and safety profile and they are fairly inexpensive. Their systemic and local side effects are mainly cardiovascular and pulmonary adverse events, dry eye and keratopathy. Latanoprost, which has recently been introduced into the market, has been shown to be equally as effective, or better in lowering IOP in patients than timolol, although it is more expensive. Systemic reported side effects are anecdotal; local hyperaemia, keratopathy, hypertrichosis, increased pigmentation of eyelashes and iris, uveitis and cystoid macular oedema have been reported. A comparison of costs reveals that a 1-year therapy with timolol ophthalmic solution starts from 11.00 Euros and can reach 146.00 Euros for the most expensive preservative-free 1-day dispenser packages (approximately 13.5 times higher). For latanoprost once-daily administration, the cost for 1 years therapy is 98.55 Euros, approximately six times higher than generic or brand 0.5% timolol applied twice-daily. What are the factors influencing a change in therapy from beta-blockers to latanoprost? The only good reason is represented by a further deterioration in the visual field. This may occur, despite a significant reduction in IOP, because the reached IOP is not sufficient enough to avoid further deterioration because the patient's work or social activities do not allow a correct daily dosage of the compound (bad compliance); or as a result of treatment suspension, because of the development of systemic and/or local side effects. Changes in therapy must always be related to a failing control of the disease, as any therapeutic modification leading to an increase in the number of visits and additional examinations, consequently enhances the costs.

Latanoprost and brimonidine: therapeutic and physiologic assessment before and after oral nonsteroidal anti-inflammatory therapy.

PURPOSE: To assess, before and during oral nonsteroidal anti-inflammatory drug coadministration, latanoprost's and brimonidine's hypotensive action in eyes at risk of glaucomatous progression, assessing the effect of each drug on ocular perfusion and visual function. METHODS: Twenty consenting adults with open-angle glaucoma or ocular hypertension underwent a double-masked, bilateral, randomized prospective study. Treatment started with either latanoprost 0.005% in the morning and placebo in the evening, or brimonidine 0.2% twice daily in one eye; after 1 week starting the other in the fellow eye. After another week, oral indomethacin 25 mg four times a day, commenced for 2 more weeks. Intraocular pressure, ocular circulation, and visual function were monitored pretreatment, after unilateral monotherapy (day 7), bilateral ocular therapy (day 14), and coadministered oral indomethacin (day 28). Intrasubject differences (interocular and intraocular relative to baseline) were determined by two-tailed paired t test. RESULTS: A loss of the significance of intraocular pressure reduction with brimonidine was noted after oral indomethacin coadministration (-14%; P =.004 for brimonidine alone versus -11%; P =.3 with indomethacin). Significant intraocular pressure reduction with latanoprost persisted despite indomethacin (-25%; P <.0001 for latanoprost alone versus -30%; P <.0001 with indomethacin). Pulsatile ocular blood flow increased 40% with latanoprost, but was unchanged with brimonidine (interdrug difference, P =.004). Midperipheral retinal microcirculation increased 23% (P =.03) with latanoprost. Humphrey perimetry and contrast sensitivity remained consistently at or above baseline with both latanoprost and brimonidine. Indomethacin had no significant effect on ocular perfusion or visual function measures. CONCLUSIONS: Circulatory and hydrodynamic findings differed substantially for the two drugs. The loss of significance of intraocular pressure reduction with brimonidine during indomethacin treatment may be clinically important.

A preliminary risk-benefit assessment of latanoprost and unoprostone in open-angle glaucoma and ocular hypertension.

Latanoprost and unoprostone (isopropyl unoprostone) represent the first commercially available prostaglandin analogues to be used for the treatment of glaucoma. Both compounds reduce intraocular pressure by enhancing uveoscleral outflow. Latanoprost, when used once daily in the evening, produces a greater reduction in pressure than timolol. Latanoprost produces mild conjunctival hyperaemia compared with timolol in some patients. Darkening of the irides has been reported, especially in green-brown, yellow-brown and blue/grey-brown irides. Hypertrichosis and hyperpigmentation of the eyelashes have also been demonstrated. Although latanoprost has not been proven to cause uveitis or cystoid macular oedema, case reports of an association exist. Latanoprost does not produce systemic adverse effects nor does it alter routine blood analyses. Unoprostone, when given twice daily, produces less of a reduction in intraocular pressure than timolol or latanoprost. Three times daily use may be required to approach the effectiveness of timolol. Unoprostone may have a similar adverse effect profile to latanoprost, but may to cause more corneal epithelial problems. Unoprostone is also not known to cause systemic adverse effects. Both agents are welcome additions to the treatment of glaucoma. However, additional studies and more experience are needed with each agents.

Ultrasonic assessment of uterine emptying in first-trimester abortions induced by intravaginal 15-methyl prostaglandin F2 alpha methyl ester.

Early first-trimester abortions were induced by a single intravaginal pessary containing 3 mg of 15 methyl prostaglandin F2 alpha methyl ester in 17 patients. The procedure was successful in 16 patients (94%). Intrauterine events were observed by means of serial ultrasonic B scans. Pain, bleeding, and dislodgement of the gestational sac had commenced within 6 hours. Significant gastrointestinal side effects occurred in the majority of patients despite medication but they were usually of short duration. Vaginal bleeding, which was not heavy, continued for about 10 days and during most of this time the uterus contained products of conception. It is concluded that the method is effective during the first 7 weeks of gestation.