Managing glaucoma in those with co-morbidity: not as easy as it seems

Prescribing Cascades with Recommendations to Prevent or Reverse Them: A Systematic Review

BACKGROUND

To reduce prescribing cascades occurring in clinical practice, healthcare providers require information on the prescribing cascades they can recognize and prevent.

OBJECTIVE

This systematic review aims to provide an overview of prescribing cascades, including dose-dependency information and recommendations that healthcare providers can use to prevent or reverse them.

METHODS

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) was followed. Relevant literature was identified through searches in OVID MEDLINE, OVID Embase, OVID CINAHL, and Cochrane. Additionally, Web of Science and Scopus were consulted to analyze reference lists and citations. Publications in English were included if they analyzed the occurrence of prescribing cascades. Prescribing cascades were included if at least one study demonstrated a significant association and were excluded when the adverse drug reaction could not be confirmed in the Summary of Product Characteristics. Two reviewers independently extracted and grouped similar prescribing cascades. Descriptive summaries were provided regarding dose-dependency analyses and recommendations to prevent or reverse these prescribing cascades.

RESULTS

A total of 95 publications were included, resulting in 115 prescribing cascades with confirmed adverse drug reactions for which at least one significant association was found. For 52 of these prescribing cascades, information regarding dose dependency or recommendations to prevent or reverse prescribing cascades was found. Dose dependency was analyzed and confirmed for 12 prescribing cascades. For example, antipsychotics that may cause extrapyramidal syndrome followed by anti-parkinson drugs. Recommendations focused on dosage lowering, discontinuing medication, and medication switching. Explicit recommendations regarding alternative options were given for three prescribing cascades. One example was switching to ondansetron or granisetron when extrapyramidal syndrome is experienced using metoclopramide.

CONCLUSIONS

In total, 115 prescribing cascades were identified and an overview of 52 of them was generated for which recommendations to prevent or reverse them were provided. Nonetheless, information regarding alternative options for managing prescribing cascades was scarce.

Anxiety, depression, and sleep-related outcomes of glaucoma patients: systematic review and meta-analysis

OBJECTIVE

This study aims to synthesize data quantifying the prevalence and severity of common psychological conditions in patients with glaucoma.

DESIGN

Systematic review and meta-analysis.

METHODS

Databases including Ovid MEDLINE, CINAHL, EMBASE, PsycINFO, Cochrane Library, Web of Science, Open Grey, and ProQuest Theses and dissertations were searched. Two reviewers independently assessed and screened all studies, followed by quality assessment of included studies using the modified Downs and Black checklist. Data were pooled using fixed-effect and random-effects models.

RESULTS

Of 2067 studies identified by the search strategy, 57 passed full-text screening, and 45 studies (4 995 538 subjects) were eligible for analysis. Overall, the prevalence of depression (effect size [ES] = 0.19, 95% CI 0.16-0.23; n = 31), anxiety (ES = 0.25, 95% CI 0.21-0.30; n = 18), and sleep disorders (ES = 0.47, 95% CI 0.26-0.68; n = 7) were high in patients with glaucoma. Similarly, symptomatic measurements of depression (standardized mean difference [SMD] = 0.46, 95% CI 0.19-0.73), anxiety (SMD = 0.44, 95% CI 0.08-0.81), and sleep quality (SMD = 0.72, 95% CI 0.22-1.21) were significant in glaucoma patients.

CONCLUSIONS

A higher prevalence and severity of depression, anxiety, and sleep disorders was experienced in patients with glaucoma compared with patients without glaucoma. Caregivers as well as health care providers may need to be aware of unique psychological and social stressors placed on glaucoma patients.

Prescribing cascades in community-dwelling adults: A systematic review

The misattribution of an adverse drug reaction (ADR) as a symptom or illness can lead to the prescribing of additional medication, referred to as a prescribing cascade. The aim of this systematic review is to identify published prescribing cascades in community-dwelling adults. A systematic review was reported in line with the PRISMA guidelines and pre-registered with PROSPERO. Electronic databases (Medline [Ovid], EMBASE, PsycINFO, CINAHL, Cochrane Library) and grey literature sources were searched. Inclusion criteria: community-dwelling adults; risk-prescription medication; outcomes-initiation of new medicine to "treat" or reduce ADR risk; study type-cohort, cross-sectional, case-control, and case-series studies. Title/abstract screening, full-text screening, data extraction, and methodological quality assessment were conducted independently in duplicate. A narrative synthesis was conducted. A total of 101 studies (reported in 103 publications) were included. Study sample sizes ranged from 126 to 11 593 989 participants and 15 studies examined older adults specifically (≥60 years). Seventy-eight of 101 studies reported a potential prescribing cascade including calcium channel blockers to loop diuretic (n = 5), amiodarone to levothyroxine (n = 5), inhaled corticosteroid to topical antifungal (n = 4), antipsychotic to anti-Parkinson drug (n = 4), and acetylcholinesterase inhibitor to urinary incontinence drugs (n = 4). Identified prescribing cascades occurred within three months to one year following initial medication. Methodological quality varied across included studies. Prescribing cascades occur for a broad range of medications. ADRs should be included in the differential diagnosis for patients presenting with new symptoms, particularly older adults and those who started a new medication in the preceding 12 months.

Prevalence and Risk Factors of Glaucoma Among Chinese People.From the China Health and Retirement Longitudinal Study

PRCIS

This study demonstrated the prevalence of self-reported glaucoma and its strong association with pre-existing systemic chronic diseases in China using the baseline data from CHARLS, a nationwide population-based cohort.

PURPOSE

To estimate the prevalence of self-reported glaucoma and its risk factors using data from the China Health and Retirement Longitudinal Study (CHARLS).

MATERIALS AND METHODS

Data on age, sex, area of residence, education, marital status, health-related behaviors, and pre-existing comorbidities for this cross-sectional study were retrieved from the CHARLS for 17,713 subjects who completed a questionnaire between June 2011 and March 2012. The prevalence of glaucoma was estimated, and a multivariate weighted analysis was performed to estimate the odds ratios (ORs) of its risk factors.

RESULTS

Of 16,599 respondents (93.7%) who answered questions regarding glaucoma and their history of systemic chronic diseases, 314 (1.89%) reported having glaucoma before the index date. Qinghai and Beijing had the highest prevalence of glaucoma in China. Glaucoma was significantly associated with hypertension (OR 1.362 [95% confidence interval (CI) 1.801-2.470]), diabetes (OR 2.597 [95% CI 1.661-10.207]), dyslipidemia (OR 1.757 [95% CI 1.157-3.650]), lung disease (OR 2.098 [95% CI 1.674-6.527]), stroke (OR 5.278 [95% CI 1.094-25.462]), heart disease (OR 1.893 [95% CI 1.237-3.363]), and health-related behaviors such as smoking and alcohol consumption after adjusting for age, sex, area, education, marital status, and medical insurance.

CONCLUSIONS

Geographic variation in the prevalence of self-reported glaucoma and its strong association with pre-existing systemic chronic diseases were observed, suggesting that in addition to ophthalmological examinations, regular physical examinations are necessary for glaucoma patients, especially in areas of high incidence. Appropriate strategies to improve preventive measures for glaucoma are recommended for the Chinese population.

Association between topical β-blocker use and asthma attacks in glaucoma patients with asthma: a cohort study using a claims database

PURPOSE

To investigate the association between the use of topical β-blockers and subsequent asthma attacks in glaucoma patients with asthma.

METHODS

This was a retrospective longitudinal cohort study using an administrative claims database. All patients aged 20 years or older who were registered in the health insurance claims database updated and managed by JMDC Inc. (Tokyo, Japan). Patients who were newly prescribed eye drops for glaucoma treatment were identified between 2011 and 2017. The patients with glaucoma were divided into two groups: β-blocker users and non-β-blocker users, based on the presence of a β-blocker in the prescribed eye drops. We investigated whether the incidence of asthma attacks in patients with previously treated asthma differed between the two groups.

RESULTS

We categorized 17,666 patients in the β-blocker-user group and 12,609 patients in the non-β-blocker-user group. A total of 580 patients in the β-blocker group (3.28%) and 847 in the non-β-blocker group (6.72%) underwent asthma treatment before the prescription of anti-glaucoma eye drops (P < 0.001). Furthermore, 94 patients in the β-blocker-user group (0.53%) and 278 in the non-β-blocker user group (2.20%) were undergoing current treatment for asthma (P < 0.001). The adjusted hazard ratios of asthma attacks were 0.73 (95% confidence interval, 0.46-1.16, P = 0.18) in patients with a history of asthma treatment and 1.22 (95% confidence interval, 0.56-2.70, P = 0.62) in patients with current asthma treatment, compared to the non-β-blocker-user group.

CONCLUSION

Our results clarified that several patients with asthma were prescribed topical β-blockers for glaucoma treatment. However, asthma attacks may not be significantly attributed to topical β-blockers, even in glaucoma patients under current asthma treatment. The administration of topical β-blockers to asthma patients could be a treatment option in the absence of other treatment options, if adequate informed consent is obtained. Further studies are needed to draw a firm conclusion on this clinical question.

Evaluating the use of prescription sequence symmetry analysis as a pharmacovigilance tool: A scoping review

BACKGROUND

The (prescription) sequence symmetry analysis (PSSA) design has been used to identify potential prescribing cascade signals by assessing the prescribing sequence of an index drug relative to a marker drug presumed to treat an adverse drug event provoked by the index drug.

OBJECTIVES

This review aimed to explore the use of the PSSA design as a pharmacovigilance tool with a particular focus on the breadth of identified signals and advances in PSSA methodology.

METHODS

We searched Embase, PubMed/Medline, Google Scholar, Web of Science and grey literature to identify studies that used the PSSA methodology. Two reviewers independently extracted relevant data for each included article. Study characteristics including signals identified, exposure time window, stratified analyses, and use of controls were extracted.

RESULTS

We identified 53 studies which reported original results obtained using PSSA methodology or quantified the validity of components of the PSSA design. Of those, nine studies provided validation metrics showing reasonable sensitivity and high specificity of PSSA to identify prescribing cascade signals. We identified 340 unique index drug - marker drug signals published in the PSSA literature, representing 281 unique index - marker pharmacological class dyads (i.e., unique fourth-level Anatomical Therapeutic Chemical [ATC] classification dyads). Commonly observed signals were identified for index drugs acting upon the nervous system (34%), cardiovascular system (21%), and blood and blood-forming organs (15%), and many marker drugs were related to the nervous system (25%), alimentary tract and metabolism (23%), cardiovascular system (17%), and genitourinary system and sex hormones (14%). Negative controls and positive controls were utilized in 21% and 13% of studies, respectively.

CONCLUSIONS

The PSSA methodology has been used in 53 studies worldwide to detect and evaluate over 300 unique prescribing cascades signals. Researchers should consider sensitivity analyses incorporating negative and/or positive controls and additional time windows to evaluate time-varying biases when designing PSSA studies.

Selective laser trabeculoplasty versus drops for newly diagnosed ocular hypertension and glaucoma: the LiGHT RCT

BACKGROUND

Newly diagnosed open-angle glaucoma (OAG) and ocular hypertension (OHT) are habitually treated with intraocular pressure (IOP)-lowering eyedrops. Selective laser trabeculoplasty (SLT) is a safe alternative to drops and is rarely used as first-line treatment.

OBJECTIVES

To compare health-related quality of life (HRQoL) in newly diagnosed, treatment-naive patients with OAG or OHT, treated with two treatment pathways: topical IOP-lowering medication from the outset (Medicine-1st) or primary SLT followed by topical medications as required (Laser-1st). We also compared the clinical effectiveness and cost-effectiveness of the two pathways.

DESIGN

A 36-month pragmatic, unmasked, multicentre randomised controlled trial.

SETTINGS

Six collaborating specialist glaucoma clinics across the UK.

PARTICIPANTS

Newly diagnosed patients with OAG or OHT in one or both eyes who were aged ≥ 18 years and able to provide informed consent and read and understand English. Patients needed to qualify for treatment, be able to perform a reliable visual field (VF) test and have visual acuity of at least 6 out of 36 in the study eye. Patients with VF loss mean deviation worse than -12 dB in the better eye or -15 dB in the worse eye were excluded. Patients were also excluded if they had congenital, early childhood or secondary glaucoma or ocular comorbidities; if they had any previous ocular surgery except phacoemulsification, at least 1 year prior to recruitment or any active treatment for ophthalmic conditions; if they were pregnant; or if they were unable to use topical medical therapy or had contraindications to SLT.

INTERVENTIONS

SLT according to a predefined protocol compared with IOP-lowering eyedrops, as per national guidelines.

MAIN OUTCOME MEASURES

The primary outcome was HRQoL at 3 years [as measured using the EuroQol-5 Dimensions, five-level version (EQ-5D-5L) questionnaire]. Secondary outcomes were cost and cost-effectiveness, disease-specific HRQoL, clinical effectiveness and safety.

RESULTS

Of the 718 patients enrolled, 356 were randomised to Laser-1st (initial SLT followed by routine medical treatment) and 362 to Medicine-1st (routine medical treatment only). A total of 652 (91%) patients returned the primary outcome questionnaire at 36 months. The EQ-5D-5L score was not significantly different between the two arms [adjusted mean difference (Laser-1st - Medicine-1st) 0.01, 95% confidence interval (CI) -0.01 to 0.03; p = 0.23] at 36 months. Over 36 months, the proportion of visits at which IOP was within the target range was higher in the Laser-1st arm (93.0%, 95% CI 91.9% to 94.0%) than in the Medicine-1st arm (91.3%, 95% CI 89.9% to 92.5%), with IOP-lowering glaucoma surgery required in 0 and 11 patients, respectively. There was a 97% probability of Laser-1st being more cost-effective than Medicine-1st for the NHS, at a willingness to pay for a quality-adjusted life-year of £20,000, with a reduction in ophthalmology costs of £458 per patient (95% of bootstrap iterations between -£585 and -£345).

LIMITATION

An unmasked design, although a limitation, was essential to capture any treatment effects on patients' perception. The EQ-5D-5L questionnaire is a generic tool used in multiple settings and may not have been the most sensitive tool to investigate HRQoL.

CONCLUSIONS

Compared with medication, SLT provided a stable, drop-free IOP control to 74.2% of patients for at least 3 years, with a reduced need for surgery, lower cost and comparable HRQoL. Based on the evidence, SLT seems to be the most cost-effective first-line treatment option for OAG and OHT, also providing better clinical outcomes.

FUTURE WORK

Longitudinal research into the clinical efficacy of SLT as a first-line treatment will specify the long-term differences of disease progression, treatment intensity and ocular surgery rates between the two pathways.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN32038223.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 23, No. 31. See the NIHR Journals Library website for further project information.

Neuropsychiatric Adverse Events from Topical Ophthalmic Timolol

Timolol is a commonly-used topical antiglaucoma medication and has proven to be highly efficacious for most recipients. Among the reported adverse events, the neuropsychiatric spectrum has been cited, albeit for a small proportion of those treated. This review summarizes the cumulative published experience of such side effects and assesses the quality of evidence. As for other beta-blockers, whether orally or topically administered, various central nervous systems dysfunctions have been detailed in either case reports or larger patient series. The adverse event commonly resolves following drug termination. Rigorous and more definitive studies of causation are lacking, and to some, such paucity has reduced the belief of a cause and effect relationship. Until otherwise proven, deference should be afforded to the potential for topical timolol to cause neuropsychiatric side effects, and at-risk patients should be closely monitored when they are prescribed this pharmacological agent.

Potentially inappropriate prescribing in people with dementia: An Australian population-based study

OBJECTIVE

To investigate the prevalence of potentially inappropriate prescribing (PIP) using the Screening Tool of Older Person's Prescriptions (STOPP) criteria in people with dementia compared with people without dementia.

METHODS

A retrospective cohort study was conducted using the Pharmaceutical Benefits Scheme 10% sample of pharmacy claims. People with dementia were defined as those dispensed a medicine for dementia (cholinesterase inhibitors, memantine, or risperidone for behavioural and psychological symptoms of dementia) between 1 January 2005 and 31 December 2015, aged 65 years or older at 1 January 2016 and alive at the end of 2016. An age- and gender-matched comparison cohort of people not dispensed medicines for dementia was identified. PIP prevalence was determined between 1 January 2016 and 31 December 2016.

RESULTS

In total, 8280 people dispensed medicines for dementia and 41 400 comparisons not dispensed medicines for dementia were included: 63% were female and the median age was 82 years. PIP prevalence was 79% among people with dementia compared with 70% among the comparison group (P < .0001). Use of anticholinergics, long-term use of high-dose proton pump inhibitors, and use of benzodiazepines were the most common instances of PIP in people with dementia. After adjustments for age, gender, comorbidity, and number of prescribers, people with dementia were more likely to be exposed to PIP than comparisons (adjusted OR 1.44, 95% CI, 1.35-1.53, P < .0001).

CONCLUSIONS

PIP was more common in people dispensed medicines for dementia than comparisons. These results highlight the need for effective interventions to optimize prescribing in people with dementia.

Effect estimate comparison between the prescription sequence symmetry analysis (PSSA) and parallel group study designs: A systematic review

Prescription sequence symmetry analysis (PSSA), a case-only design introduced in 1996, has been increasingly used to identify unintentional drug effects, and has potential applications as a hypothesis-testing and a hypothesis-generating method, due to its easy application and effective control of time-invariant confounders. The aim of this study is to systematically compare effect estimates from the PSSA to effect estimates from conventional observational parallel group study designs, to assess the validity and constraints of the PSSA study design. We reviewed the MEDLINE, EMBASE, and Web of Science databases until February 2016 to identify studies that compared PSSA to a parallel group design. Data from the eligible articles was extracted and analyzed, including making a Bland-Altman plot and calculating the number of discrepancies between the designs. 63 comparisons (from two studies) were included in the review. There was a significant correlation (p < 0.001) between the effect estimates of the PSSA and the parallel group designs, but the bias indicated by the Bland-Altman plot (0.20) and the percentage of discrepancies (70–80%) showed that this correlation was not accompanied by a considerable similarity of the effect estimates. Overall, the effect estimates of the parallel group designs were higher than those of the PSSA, not necessarily further away from 1, and the parallel group designs also generated more significant signals. However, these results should be approached with caution, as the effect estimates were only retrieved from two separate studies. This review indicates that, even though PSSA has a lot of potential, the effect estimates generated by the PSSA are usually lower than the effect estimates generated by parallel group designs, and PSSA mostly has a lower power than the conventional study designs, but this is based on limited comparisons, and more comparisons are needed to make a proper conclusion.

Assessment of Medication Safety Using Only Dispensing Data

PURPOSE OF REVIEW

The purpose of this review is to provide an overview of the published studies that have been used to generate evidence on the safety of medicine use when only medication dispensing data are available.

RECENT FINDINGS

Medication dispensing databases are increasingly available for research on large populations, particularly in countries that provide universal coverage for medicines. These data are often used for drug utilisation studies to identify inappropriate medicine use at the population level that may be associated with known safety issues. Lack of coded diagnoses, to identify outcomes, and lack of data on confounders can limit use of these data in practice for medication safety assessment. To overcome these issues, studies have exploited the fact that symptoms of adverse effects of medications can be treated with other medications, for example antidepressants to treat depression or oxybutynin to treat urinary incontinence. The challenge of unmeasured confounding has been addressed by implementing self-controlled study designs that use within-person comparisons and provide inherent control for confounding. Prescription sequence symmetry analysis (SSA) is a within-person study design that has been demonstrated as a useful tool for safety signal generation in dispensing data.

SUMMARY

Using medicine initiation as a proxy for the development of adverse events can help to generate evidence of the safety of medicines when only medication dispensing data are available. Careful consideration, however, should be given to the sensitivity and specificity of the proxy medicine for the adverse event and potential for time-varying confounding due to trends in medicine utilisation. Data-mining approaches using dispensing data have the potential to improve safety assessments; however, the challenge of unmeasured confounding with these methods remains to be investigated.

Pharmacodynamic profile of mydriatic agents delivered by ocular piezo-ejection microdosing compared with conventional eyedropper

AIM

Eyedroppers deliver medication volumes exceeding conjunctival absorptive capacity, causing spillage and risking ocular/systemic complications. We evaluated piezoelectric microdosing. Results/methodology: Subjects (n = 102) received precision microdroplet delivery of phenylephrine (2.5%) and tropicamide (1.0%): 1 × 1.5 μl, 1 × 6 μl or 2 × 3 μl of each (randomized 1:1:1), into one eye. Contralateral eyes received eyedropper doses of both drugs. Outcomes were pupil dilation (0-60 min) and patient satisfaction. Six-microliter microdosing achieved comparable, and 2 × 3 μl met/exceeded dilation speed and magnitude versus eyedropper. Separately, participants preferred piezoelectric saline self-delivery to eyedroppers, reporting better head-positioning comfort, reduced tearing/overflow and increased likelihood of adhering to ocular medication regimens.

CONCLUSION

Piezoelectric microdosing achieves comparable effects as eyedroppers delivering 4-17-fold larger doses. Microdosing may enhance patient adherence to ocular medication regimens while minimizing side effects.

Psychological Aspects of Glaucoma

Glaucoma is a group of optic neuropathies that is more prevalent among the elderly population and commonly associates with comorbidities, including mental disorders in that population. This article reviews the relationship between glaucoma and mental disorders. In it, we discuss the coexistence of glaucoma and mental illnesses, including Alzheimer's disease, depression, and personality disorder. We also focus on the proper treatment approaches for glaucoma patients with mental comorbidity and poor treatment adherence. We summarize some cautiously recommended psychotherapeutic medications, while also discussing the psychologically adverse effects of antiglaucoma medications.

Studies using Australia's Pharmaceutical Benefits Scheme data for pharmacoepidemiological research: a systematic review of the published literature (1987-2013)

PURPOSE

Research using dispensing claims is used increasingly to study post-market medicines use and outcomes. The purpose of this review is to catalogue more than 25 years of published literature using Australia's Pharmaceutical Benefits Scheme (PBS) dispensing records.

METHODS

We searched MEDLINE, PreMEDLINE and Embase and conducted author searches for studies published from 1987 to 2013. Independent reviewers screened abstracts of 3209 articles and reviewed 264 full-text manuscripts. Included studies used PBS dispensing data to measure patterns and/or outcomes of prescribed medicines use or dispensing claims to derive a proxy for a specific disease cohort or health outcome.

RESULTS

Of the 228 studies identified, 106 used PBS claims only (56 using claims-level data and 50 using individual-level data) and 63 studies linked individual-level PBS claims to other health data. Most commonly, studies examined trends in drug utilisation (33%), clinician and patient practices (26%), drug use and outcomes (18%) and evaluations of intervention impacts (17%). Sixty-two percent of studies using individual-level data were based on a subset of elderly Australians. Most studies focused on drug classes acting on the nervous system (36%), cardiovascular system (15%) and alimentary tract (11%). Few studies examined prescribed medicines use in children and pregnant women.

CONCLUSIONS

Pharmaceutical Benefits Scheme claims represent a significant resource to examine Australia's billion-dollar annual investment in prescribed medicines. The body of research is growing and has increased in complexity over time. Australia has great potential to undertake world-class, whole-of-population pharmacoepidemiological studies. Recent investment in data linkage infrastructure will significantly enhance these opportunities.

Association between Ophthalmic Timolol and Hospitalisation for Bradycardia

Introduction. Ophthalmic timolol, a topical nonselective beta-blocker, has the potential to be absorbed systemically which may cause adverse cardiovascular effects. This study was conducted to determine whether initiation of ophthalmic timolol was associated with an increased risk of hospitalisation for bradycardia. Materials and Methods. A self-controlled case-series study was undertaken in patients who were hospitalised for bradycardia and were exposed to timolol. Person-time after timolol initiation was partitioned into risk periods: 1–30 days, 31–180 days, and >180 days. A 30-day risk period prior to initiating timolol was also included. All remaining time was considered unexposed. Results. There were 6,373 patients with at least one hospitalisation for bradycardia during the study period; 267 were exposed to timolol. Risk of bradycardia was significantly increased in the 31–180 days after timolol initiation (incidence rate ratio (IRR) = 1.93; 95% confidence interval (CI) 1.00–1.87). No increased risk was observed in the first 30 days or beyond 180 days of continuous exposure (IRR = 1.40; 95% CI 0.87–2.26 and IRR = 1.21; 95% CI 0.64–2.31, resp.). Conclusion. Bradycardia is a potential adverse event following timolol initiation. Practitioners should consider patient history before choosing a glaucoma regime and closely monitor patients after treatment initiation with topical nonselective beta-blocker eye drops.

Brinzolamide plus brimonidine for the treatment of glaucoma: an update

INTRODUCTION

Glaucoma is a common sight-threatening condition that is primarily treated by lowering intraocular pressure (IOP). Today the mainstay of treatment is topical ocular hypotensive medications; many patients require more than one agent to achieve target IOP. For such patients, fixed combination formulations have several advantages including simplicity of treatment regimen, adherence to the treatment regimen, efficacy, improved ocular surface comfort and reduced cost. All currently available fixed combinations contain a β-blocker, which is contraindicated in some patients. Hence there is a clinical need for fixed-combination preparations without a β-blocker. This paper reviews the current literature on a new fixed-combination drug containing brinzolamide 1% and brimonidine 0.2% (BBFC).

AREAS COVERED

A PubMed, Embase and ClinicalTrials.gov registry search was performed to identify all relevant studies. Four published clinical papers pertaining to three randomized controlled trials were identified for review. All studies demonstrated a significant reduction (p < 0.01) in mean IOP in patients administered with BBFC compared with its individual components, brinzolamide 1% or brimonidine 0.2%. Adverse effects from BBFC were no different from each of the individual components, the most common being blurred vision, eye irritation and dysgeusia (abnormal taste sensation). Although BBFC use was associated with more adverse effects compared with the individual components used as monotherapy (p < 0.001), the cumulative adverse effect profile from BBFC did not appear greater than one would expect from the simultaneous use of the two components.

EXPERT OPINION

BBFC is a potential alternative to other fixed-combination medications and is especially useful when topical β-blockers are contraindicated. Longer-term experience will determine if additional adverse effects occur or if efficacy is maintained over longer periods.

Six-month results from a Phase III randomized trial of fixed-combination brinzolamide 1% + brimonidine 0.2% versus brinzolamide or brimonidine monotherapy in glaucoma or ocular hypertension

Background

The objective of this study was to examine the safety and intraocular pressure (IOP)-lowering efficacy of a fixed combination of brinzolamide 1% + brimonidine 0.2% (BBFC) after six months of treatment in patients with open-angle glaucoma or ocular hypertension.

Methods

This was a randomized, multicenter, double-masked, three-month, three-arm contribution-of-elements study with a three-month safety extension. Patients were randomly assigned 1:1:1 to treatment with BBFC, brinzolamide 1%, or brimonidine 0.2% after a washout period. Patients dosed their study medications three times daily at 8 am, 3 pm, and 10 pm for six months. Patients returned for visits at two weeks, six weeks, three months, and six months. IOP measurements were used to assess efficacy. Safety assessments were adverse events, corrected distance visual acuity, slit-lamp biomicroscopy, pachymetry, perimetry, fundus parameters, and cardiac parameters.

Results

A total of 690 patients were randomized. Six-month mean IOP values were similar to those at three months, when the mean IOP in patients treated with BBFC was significantly lower than that of either monotherapy group. A total of 175 patients experienced at least one treatment-related adverse event (BBFC, 33.0%; brinzolamide, 18.8%; brimonidine, 24.7%), eight of which were severe, and five resulted in discontinuation. Seventy-seven patients discontinued participation due to treatment-related adverse events (BBFC, 17.2%; brinzolamide, 2.1%; brimonidine, 14.5%). There were 21 serious adverse events (n = 7 in each group), none of which was related to treatment. Resting mean pulse and blood pressure with BBFC were similar to those with brimonidine, demonstrating modest, clinically insignificant decreases. No new or increased risks were identified with use of BBFC relative to either monotherapy.

Conclusion

This study showed that, after six months of treatment, the safety profile of BBFC was similar to that of its individual components and its IOP-lowering activity was similar to its efficacy at three months, when it was superior to both brinzolamide 1% alone and brimonidine 0.2% alone.

Fixed-combination brinzolamide 1%/brimonidine 0.2% vs monotherapy with brinzolamide or brimonidine in patients with open-angle glaucoma or ocular hypertension: results of a pooled analysis of two phase 3 studies

Purpose

To describe pooled efficacy and safety data from two phase 3 studies comparing brinzolamide 1%/brimonidine 0.2% fixed combination (BBFC) with its component medications, brinzolamide and brimonidine, in patients with open-angle glaucoma or ocular hypertension.

Methods

Data were pooled from two nearly identical clinical trials comparing BBFC with its component medications, each given three times daily. The 3-month efficacy outcome was mean intraocular pressure (IOP) at 0800, 1000, 1500, and 1700 hours. Safety outcomes included adverse events (AEs), best-corrected visual acuity, examination of ocular structures, pachymetry, perimetry, and vital signs.

Results

A total of 1350 patients were enrolled and included in this analysis (BBFC, n=437; brinzolamide, n=458; brimonidine, n=455). Baseline mean IOP levels were similar among the three treatment groups. At 3 months, mean IOP of the BBFC group was significantly lower than that of either monotherapy group (P<0.0001) at all the four time points. A total of 272 patients (20.1%) experienced at least one treatment-related AE (BBFC, 24.6% brinzolamide, 18.7% brimonidine, 17.4%), the majority of which were ocular AEs. One serious AE, moderate intensity chest pain, was considered related to brinzolamide treatment and resulted in study discontinuation.

Conclusions

This analysis strengthens the conclusions drawn from the two individual phase 3 studies showing that, in patients with open-angle glaucoma or ocular hypertension, BBFC had significantly superior IOP-lowering activity compared with either brinzolamide or brimonidine alone and a safety profile consistent with that of its individual components.