Michael R. Paterno

Besifloxacin ophthalmic suspension 0.6% in patients with bacterial conjunctivitis: A multicenter, prospective, randomized, double-masked, vehicle-controlled, 5-day efficacy and safety study

BACKGROUND Besifloxacin ophthalmic suspension 0.6% is a new topical fluoroquinolone for the treatment of bacterial conjunctivitis. Besifloxacin has potent in vitro activity against a broad spectrum of ocular pathogens, including drug-resistant strains. OBJECTIVE The primary objective of this study was to compare the clinical and microbiologic efficacy of besifloxacin ophthalmic suspension 0.6% with that of vehicle (the formulation without besifloxacin) in the treatment of bacterial conjunctivitis. METHODS This was a multicenter, prospective, randomized, double-masked, vehicle-controlled, parallel-group study in patients with acute bacterial conjunctivitis. Patients received either topical besifloxacin ophthalmic suspension or vehicle administered 3 times daily for 5 days. At study entry and on days 4 and 8 (visits 2 and 3), a clinical assessment of ocular signs and symptoms was performed in both eyes, as well as pinhole visual acuity testing, biomicroscopy, and culture of the infected eye(s). An ophthalmoscopic examination was performed at study entry and on day 8. The primary efficacy outcome measures were clinical resolution and eradication of the baseline bacterial infection on day 8 in culture-confirmed patients. The safety evaluation included adverse events, changes in visual acuity, and biomicroscopy and ophthalmoscopy findings in all patients who received at least 1 dose of active treatment or vehicle. RESULTS The safety population consisted of 269 patients (mean [SD] age, 34.2 [22.3] years; 60.2% female; 82.5% white) with acute bacterial conjunctivitis. The culture-confirmed intent-to-treat population consisted of 118 patients (60 besifloxacin ophthalmic suspension, 58 vehicle). Significantly more patients receiving besifloxacin ophthalmic suspension than vehicle had clinical resolution of the baseline infection at visit 3 (44/60 [73.3%] vs 25/58 [43.1%], respectively; P < 0.001). Rates of bacterial eradication also were significantly greater with besifloxacin ophthalmic suspension compared with vehicle at visit 3 (53/60 [88.3%] vs35/58 [60.3%]; P < 0.001). The cumulative frequency of adverse events did not differ significantly between the 2 groups (69/137 [50.4%] and 70/132 [53.0%]). The most common ocular adverse events were eye pain (20/190 treated eyes [10.5%] and 13/188 [6.9%]), blurred vision (20/190 [10.5%] and 22/188 [11.7%]), and eye irritation (14/190 [7.4%] and 23/188 [12.2%]); these events were of mild or moderate severity. Changes in visual acuity and treatment-emergent events observed on biomicroscopy and direct ophthalmoscopy also were comparable between treatment groups. CONCLUSION Besifloxacin ophthalmic suspension 0.6% given 3 times daily for 5 days was both efficacious and well tolerated compared with vehicle in the treatment of these patients with bacterial conjunctivitis. ClinicalTrials.gov Identifier: NCT00622908.

Phase III efficacy and safety study of besifloxacin ophthalmic suspension 0.6% in the treatment of bacterial conjunctivitis

ABSTRACT Objective: To compare the clinical and antimicrobial efficacy of besifloxacin ophthalmic suspension 0.6% with that of vehicle in the treatment of bacterial conjunctivitis. Research design and methods: This was a randomized, multicenter, double-masked, vehicle-controlled study. A total of 957 patients aged 1 year and older with bacterial conjunctivitis were randomized to treatment with besifloxacin ophthalmic suspension 0.6% or vehicle applied topically three times daily for 5 days. Main outcome measures: Primary endpoints were clinical resolution and microbial eradication of baseline bacterial infection at Visit 2 (Day 5 ± 1). Secondary endpoints included clinical resolution and microbial eradication at Visit 3 (Day 8 or 9), individual clinical outcomes at follow-up visits, and safety. Clinical trial registration: NCT number, NCT00347932. Results: Three hundred and ninety patients had culture-confirmed bacterial conjunctivitis. Clinical resolution and microbial eradication were significantly greater with besifloxacin ophthalmic suspension than with vehicle at Visit 2 (45.2% vs. 33.0%, p = 0.0084; and 91.5% vs. 59.7%, p < 0.0001, respectively) and Visit 3 (84.4% vs. 69.1%, p = 0.0011; and 88.4% vs. 71.7%, p < 0.0001, respectively). Results for secondary endpoints of individual clinical outcomes were consistent with primary endpoints. Fewer eyes receiving besifloxacin ophthalmic suspension experienced adverse events than those receiving vehicle (9.2% vs. 13.9%; p = 0.0047). Conclusions: Besifloxacin ophthalmic suspension produces clinical resolution and microbial eradication rates significantly better than vehicle and is safe for the treatment of bacterial conjunctivitis. Limitations: A limitation of this study is the lack of a non-treatment control group.

Efficacy and Safety of Besifloxacin Ophthalmic Suspension 0.6% Compared with Moxifloxacin Ophthalmic Solution 0.5% for Treating Bacterial Conjunctivitis

OBJECTIVE To compare the clinical and antimicrobial efficacy of besifloxacin ophthalmic suspension 0.6% with that of moxifloxacin ophthalmic solution 0.5% for the treatment of bacterial conjunctivitis. DESIGN Multicenter, randomized, double-masked, parallel-group, active-controlled, noninferiority study. PARTICIPANTS Patients 1 year of age or older with clinical manifestations of bacterial conjunctivitis. METHODS Eligible patients were randomized to either besifloxacin suspension or moxifloxacin solution, instilled in the infected eye(s) 3 times daily for 5 days, and participated in study visits on days 1, 5 (+/-1 day), and 8 (+1 day). Assessments included clinical evaluation of signs and symptoms, visual acuity, biomicroscopy, and culture of the infected eye(s) at each visit, as well as direct ophthalmoscopy on days 1 and 8. MAIN OUTCOME MEASURES The primary efficacy end points were clinical resolution and microbial eradication of baseline bacterial infection on day 5 in patients with culture-confirmed bacterial conjunctivitis. Secondary end points included clinical resolution and microbial eradication on day 8, individual clinical outcomes, microbial and clinical outcomes by bacterial species, and safety. RESULTS A total of 1161 patients (533 with culture-confirmed bacterial conjunctivitis) were randomized. Based on the 95% confidence interval (CI) of the difference, besifloxacin was noninferior to moxifloxacin for clinical resolution on day 5 (58.3% vs. 59.4%, respectively; 95% CI, -9.48 to 7.29) and day 8 (84.5% vs. 84.0%, respectively, 95% CI, -5.6% to 6.75%) and for microbial eradication on day 5 (93.3% vs. 91.1%, respectively, 95% CI, -2.44 to 6.74) and day 8 (87.3% vs. 84.7%; 95% CI, -3.32 to 8.53). There was no statistically significant difference between the 2 treatment groups for either efficacy end points on days 5 or 8 (P>0.05). Besifloxacin and moxifloxacin were well tolerated. The cumulative frequency of ocular adverse events was similar between treatments (12% and 14% with besifloxacin and moxifloxacin, respectively). However, eye irritation occurred more often in moxifloxacin-treated eyes (0.3% for besifloxacin vs. 1.4% for moxifloxacin; P = 0.0201). CONCLUSIONS Besifloxacin ophthalmic suspension was non inferior to moxifloxacin ophthalmic suspension and provided similar safety and efficacy (clinical and microbiological) outcomes when used for the treatment of bacterial conjunctivitis. FINANCIAL DISCLOSURE(S) Proprietary or commercial disclosure may be found after the references.

Ocular Pharmacokinetics of Besifloxacin Following Topical Administration to Rabbits, Monkeys, and Humans

PURPOSE Studies were conducted to evaluate the ocular penetration and systemic exposure to besifloxacin, a fluoroquinolone antibiotic, following topical ocular administration to animals and humans. METHODS Besifloxacin ophthalmic suspension (0.6%) was administered as a topical ocular instillation to pigmented rabbits, cynomolgus monkeys, and human subjects. At predetermined intervals after dosing, samples of ocular tissues and plasma were collected and analyzed for besifloxacin levels using HPLC/MS/MS methods. RESULTS Besifloxacin demonstrated good ocular penetration in rabbits and monkeys, with rapid absorption and sustained concentrations observed in anterior ocular tissues through 24 h after a single administration. Maximum besifloxacin concentrations in conjunctiva, cornea, and aqueous humor of monkeys were 6.43 microg/g, 2.10 microg/g, and 0.796 microg/mL, respectively, after a single topical dose, and concentrations declined in these tissues with an apparent half-life of 5-14 h. Following a single topical ocular administration to humans, the maximum besifloxacin concentration in tears was 610 microg/g with concentrations decreasing to approximately 1.6 microg/g at 24 h. The resulting pharmacokinetic parameters for besifloxacin in human tears were evaluated relative to the MIC(90) values (microg/mL) for besifloxacin against Streptococcus pneumoniae (0.125), Staphylococcus aureus (0.25), Staphylococcus epidermidis (0.5), and Haemophilus influenzae (0.06). Following a single topical administration, the C(max)/MIC(90) ratios for besifloxacin in human tears were > or =1,220, and the AUC((0-24))/MIC(90) ratios were > or =2,500 for these relevant ocular pathogens. Following repeated 3-times daily (TID) topical ocular administration to human subjects with clinically diagnosed bacterial conjunctivitis, maximum besifloxacin concentrations in plasma were less than 0.5 ng/mL, on average. CONCLUSIONS Taken together, the results of the current investigation provide a PK/PD-based rationale that supports the use of besifloxacin for the safe and effective treatment of ocular infections.

Effects of loteprednol/tobramycin versus dexamethasone/tobramycin on intraocular pressure in healthy volunteers.

Purpose: To compare the steroid-induced intraocular pressure (IOP) and other ocular adverse effects of loteprednol etabonate 0.5% and tobramycin 0.3% ophthalmic suspension with those of dexamethasone 0.1% and tobramycin 0.3% ophthalmic suspension. Methods: Three hundred six healthy volunteers received either loteprednol etabonate/tobramycin (n = 156) or dexamethasone/tobramycin (n = 150) at 4-hour intervals 4 times a day in both eyes for 28 days in this randomized, double-masked, multicenter, parallel-group trial. IOP, visual acuity (VA), and ocular health were assessed at all study visits (days 1, 3, 8, 15, 22, and 29), whereas undilated direct ophthalmoscopy was completed at the baseline and final visits. Adverse events (AEs) were assessed at all follow-up visits. Results: The number of subjects experiencing IOP increases of ≥10 mm Hg from baseline at any study visit for the loteprednol etabonate/tobramycin group (3 subjects, 1.95%) was significantly lower than that for the dexamethasone/tobramycin group (11 subjects, 7.48%; P = 0.0280), as were mean changes from baseline IOP (P < 0.05 at all visits). The lowest VA recorded for any subject at any visit was 20/40 and reductions of ≥2 lines at any visit were observed in 14 (4.55%) eyes for loteprednol etabonate/tobramycin and in 23 (7.82%) eyes for dexamethasone/tobramycin (P = 0.1257). Both treatments were well tolerated. Conclusions: Loteprednol/tobramycin was significantly less likely to produce elevations in IOP than was dexamethasone/tobramycin in healthy subjects treated for 28 days. Both loteprednol etabonate/tobramycin and dexamethasone/tobramycin were well tolerated with low risks for systemic AEs and ocular AEs other than elevation in IOP for dexamethasone/tobramycin.

Safety and efficacy of loteprednol etabonate ophthalmic ointment 0.5% for the treatment of inflammation and pain following cataract surgery

Background: To compare the safety and efficacy of loteprednol etabonate ophthalmic ointment 0.5% (LE ointment), a new topical ointment formulation, with vehicle for the treatment of inflammation and pain following cataract surgery. Methods: Two randomized, multicenter, double-masked, parallel-group, vehicle-controlled studies were conducted. Patients aged ≥18 years with a combined postoperative anterior chamber cells and flare (ACI) ≥ Grade 3 following uncomplicated cataract surgery participated in seven study visits. Patients self-administered either topical LE ointment or vehicle four times daily for 14 days. Efficacy outcomes included the proportion of patients with complete resolution of ACI and the proportion of patients with no (Grade 0) pain at postoperative day 8. Safety outcomes included the incidence of adverse events, ocular symptoms, changes in intraocular pressure and visual acuity, and biomicroscopy and funduscopy findings. Results: Data from the two studies were combined. The integrated intent-to-treat population consisted of 805 patients (mean [standard deviation] age 69.0 [9.2] years; 58.0% female and 89.7% white). Significantly more LE ointment-treated patients than vehicle-treated patients had complete resolution of ACI (27.7% versus 12.5%) and no pain (75.5% versus 43.1%) at day 8 (P < 0.0001 for both). Fewer LE ointment-treated patients required rescue medication (27.7% versus 63.8%), and fewer had an ocular adverse event (47.2% versus 78.0%, P < 0.0001) while on study treatment. The most common ocular adverse events with LE ointment were anterior chamber inflammation, photophobia, corneal edema, conjunctival hyperemia, eye pain, and iritis. Mean intraocular pressure decreased in both treatment groups. Four patients had increased intraocular pressure ≥10 mmHg (three LE ointment and one vehicle) prior to rescue medication. Visual acuity and dilated funduscopy results were similar between the treatment groups, with the exception of visual acuity at visits 5 and 6, which favored LE ointment. Conclusion: LE ointment was efficacious and well tolerated in the treatment of ocular inflammation and pain following cataract surgery.

Efficacy and Safety of Besifloxacin Ophthalmic Suspension 0.6% in Children and Adolescents with Bacterial Conjunctivitis

AbstractBackground: Acute conjunctivitis is the most frequent eye disorder seen by primary care physicians and one that often affects children. Besifloxacin is a new topical fluoroquinolone, the first chlorofluoroquinolone, for the treatment of bacterial conjunctivitis. Objective: To examine the efficacy and safety of besifloxacin ophthalmic suspension 0.6% in patients aged 1–17 years with bacterial conjunctivitis. Methods: This was a post hoc analysis of a subgroup of pediatric patients aged 1–17 years who had participated in three previously reported, randomized, double-masked, parallel-group, multicenter, clinical trials evaluating the safety and efficacy of besifloxacin in the treatment of bacterial conjunctivitis. The studies were conducted in a community setting (clinical centers). All three clinical trials included children (aged ≥1 year) with a clinical diagnosis of bacterial conjunctivitis in at least one eye, based on the presence at baseline of grade 1 or greater purulent conjunctival discharge and conjunctival injection, and pin-hole visual acuity of at least 20/200 in both eyes for verbal patients. Two trials were vehicle controlled; the third trial was comparator controlled (moxifloxacin hydrochloride ophthalmic solution 0.5% as base). In all studies, besifloxacin ophthalmic suspension 0.6% was administered as one drop in the affected eye(s) three times daily, at approximately 6-hourly intervals, for 5 days. The main outcome measures were clinical resolution and microbial eradication at visit 2 (day 4 ± 1 in one study; day 5 ± 1 in the other two studies) and visit 3 (day 8 or 9). Data from the two vehicle-controlled studies were combined for the assessments to provide greater statistical power. Results: This analysis included 815 pediatric patients aged 1–17 years (447 with culture-confirmed bacterial conjunctivitis). Clinical resolution was significantly greater (p < 0.05) in the besifloxacin group than in the vehicle group at both visit 2 (53.7% vs 41.3%) and visit 3 (88.1% vs 73.0%). Similarly, microbial eradication was significantly higher with besifloxacin than with vehicle at visit 2 (85.8% vs 56.3%) and visit 3 (82.8% vs 68.3%). No significant differences in clinical resolution and microbial eradication were noted between besifloxacin and moxifloxacin. Besifloxacin was well tolerated, with similar incidences of adverse events in the besifloxacin, vehicle, and moxifloxacin groups. Conclusion: Besifloxacin ophthalmic suspension 0.6% was shown to be safe and effective for the treatment of bacterial conjunctivitis in children and adolescents aged 1–17 years.

Safety and tolerability of besifloxacin ophthalmic suspension 0.6% in the treatment of bacterial conjunctivitis: data from six clinical and phase I safety studies.

AbstractBackground: Besifloxacin is a novel fluoroquinolone, specifically a chlorofluoroquinolone, with potent broad-spectrum bactericidal activity for the topical treatment of bacterial conjunctivitis. Objective: The objective of this report was to provide a comprehensive assessment of the safety and tolerability of besifloxacin ophthalmic suspension 0.6% across clinical and phase I safety studies. Methods: Data were drawn from two phase I safety studies in healthy adults, an open-label, phase II pharmacokinetic study of patients with bacterial conjunctivitis and from integrated data from three randomized, double-masked, parallel-group, safety and efficacy studies of patients with bacterial conjunctivitis (two were vehicle controlled and one was active controlled with moxifloxacin ophthalmic solution 0.5%, as base). Safety assessments included changes in visual acuity, ocular assessments with ophthalmoscopy and biomicroscopy, and assessment of adverse events (AEs). Results: Safety data for besifloxacin ophthalmic suspension 0.6% were available for 1350 patients, including 1192 patients (1810 eyes) in the integrated analysis. Systemic exposure following topical administration of besifloxacin ophthalmic suspension 0.6% was negligible. No changes were seen in corneal endothelial cell density. In the integrated safety analysis of the three safety and efficacy studies, the most commonly reported ocular AEs in study eyes receiving besifloxacin ophthalmic suspension 0.6% were blurred vision (2.1 %), eye pain (1.8%), eye irritation (1.4%), nonspecific conjunctivitis (1.2%) and eye pruritus (1.1%). Blurred vision, eye irritation and nonspecific conjunctivitis occurred in significantly fewer besifloxacin-treated patients than in vehicle-treated patients (p≤0.05). Headache (1.8%) was the most frequently reported non-ocular AE. Most AEs were mild in severity and there were no treatment-related serious AEs. Besifloxacin ophthalmic suspension 0.6% did not significantly affect visual acuity, biomicroscopy or ophthalmoscopy compared with vehicle or moxifloxacin. Conclusion: The results from this comprehensive data set of 1350 patients demonstrate that besifloxacin ophthalmic suspension 0.6% has a favourable safety profile and is well tolerated.

Limitations of current antibiotics for the treatment of bacterial conjunctivitis.

Bacterial conjunctivitis is a common ocular infection that is generally treated empirically with a broad-spectrum antibiotic. The more common pathogens causing bacterial conjunctivitis include Staphylococcus aureus, Haemophilus influenzae, Streptococcus pneumoniae, Staphylococcus epidermidis, and Moraxella species. Several antibiotics traditionally used to treat bacterial conjunctivitis are no longer widely prescribed because of increased bacterial resistance and/or safety concerns. The introduction of the fluoroquinolone class of anti-infectives offered effective and better tolerated treatment options. Nonetheless, successful therapy for bacterial conjunctivitis continues to be limited by several factors. A primary concern is the development of bacterial resistance that may be impacted not only by widespread antibiotic use but also by antibacterial pharmacokinetics, such as maintenance of insufficient bactericidal concentrations at the site of infection. In addition, poor adherence to prescribed regimens that require frequent administration, along with undesirable adverse events, affects the development of bacterial resistance and the success of treatment regimens. This article reviews current antibacterial agents used to treat bacterial conjunctivitis, factors that limit their successful use in treatment, and options for future development of more effective topical ophthalmic anti-infective agents.

Safety and Tolerability of Loteprednol Etabonate 0.5% and Tobramycin 0.3% Ophthalmic Suspension in Pediatric Subjects

BackgroundLoteprednol etabonate 0.5% and tobramycin 0.3% ophthalmic suspension (LE/T) is indicated for steroid-responsive inflammatory ocular conditions where superficial bacterial ocular infection or a risk of bacterial ocular infection exists. LE/T was shown to be safe in healthy volunteers and patients aged 18 years and older with minimal effect on intraocular pressure (IOP).ObjectiveThe aim of the study was to evaluate the safety of LE/T in pediatric subjects by examining data from two clinical studies.MethodsTwo randomized, multicenter, double-masked, parallel-group (one two-arm, the other four-arm) studies were conducted in subjects aged 0–6 years (N = 245). One study assessed LE/T compared with vehicle in the management of lid inflammation (n = 108) and the other compared LE/T with loteprednol etabonate ophthalmic suspension 0.5% (LE), tobramycin ophthalmic solution 0.3% (tobramycin), and vehicle in the treatment of blepharoconjunctivitis (n = 137). In the first study, subjects were randomized to LE/T or vehicle administered four times daily (qid) for the first 7 days followed by twice daily (bid) for 7 days along with warm compresses bid for the entire 2 weeks. In the second study, subjects were randomized to LE/T, LE, tobramycin, or vehicle administered qid for 14 days. Treatment-emergent ocular and non-ocular adverse events (AEs) and bilateral vision were assessed at all study visits in both studies. In addition, in the lid inflammation study, IOP was assessed at all visits. The primary safety endpoint in both studies was the incidence of treatment-emergent AEs.ResultsThe incidence of LE/T treatment-emergent AEs was low. A total of four ocular AEs were reported for three LE/T-treated subjects in the first study (conjunctivitis [two events], meibomian gland dysfunction, and corneal staining), and one ocular AE was reported for an LE/T-treated subject in the second study (eye pain). A total of 13 non-ocular AEs were reported for eight LE/T-treated subjects in the two trials. The most prevalent non-ocular AEs were pyrexia (three events) and rash (two events). There were no differences in the incidence of specific ocular and non-ocular AEs between the LE/T group and the comparator treatment group. In both studies, there were no clinically meaningful reductions in vision at follow-up visits. Mean IOP and IOP changes from baseline, assessed in the lid inflammation study, were not different between LE/T and vehicle treatment groups at any study visits.ConclusionThe results of these two clinical trials demonstrate the short-term safety of treatment with topical LE/T in pediatric subjects (0–6 years of age) with lid inflammation or blepharoconjunctivitis.