Intensified monitoring of circadian blood pressure and heart rate before and after intravitreous injection of bevacizumab: preliminary findings of a pilot study

Short-term effects of intravitreal ranibizumab and bevacizumab administration on 24-h ambulatory blood pressure monitoring recordings in normotensive patients with age-related macular degeneration

PurposeTo evaluate effects of intravitreal ranibizumab and bevacizumab administration on ambulatory blood pressure monitoring (ABPM) recordings in normotensive patients with age-related macular degeneration (AMD).Patients and methodsA total of 72 patients (mean age: 61.8(6.2) years, 52.8% were females) diagnosed with AMD were included in this study as divided into ranibizumab (n=34) and bevacizumab (n=38) treatment groups. Twenty-four hour, nighttime, and daytime ABMP values for systolic and diastolic BP were recorded in study groups before and after the third intravitreal injection of ranibizumab or bevacizumab.ResultsRanibizumab injection had no impact on ABPM recordings and dipping status. In the bevacizumab group, increased daytime (129.0(6.6) vs 127.7(6.6) mm Hg, P=0.002) and nighttime systolic (116.9(7.5) vs 112.6(7.1) mmHg, p<0.001) BP and decreased daytime diastolic (80.1(6.5) vs 82.4(6.1)mm Hg, P=0.001) BP were noted in the post-injection period. Also, percentage of non-dippers was significantly increased from 5.3% at pre-injection to 28.9% (P=0.004) at the post-injection period.ConclusionIn conclusion, given that it has no significant impact on ABPM recordings and dipping status, in our study, intravitreal ranibizumab injection may be the better choice in the management of AMD.

Systemic thromboembolic adverse events in patients treated with intravitreal anti-VEGF drugs for neovascular age-related macular degeneration: an overview

INTRODUCTION

Anti-VEGF therapy improved the quality of life for millions of patients suffering from wet age-related macular degeneration (wet-AMD); unfortunately, this therapy involves multiple injections over many years. The administration of anti-VEGF can overcome the blood-retinal barrier with agents entering the systemic circulation and causing a significant decrease in VEGF serum concentration. Although circulating VEGF protects the integrity and patency of vessels, prolonged anti-VEGF treatment has the potential to increase the risk of thromboembolic events.

AREAS COVERED

In this review, we discuss the safety data from recent trials involving available anti-VEGF drugs.

EXPERT OPINION

During the 2 years of follow-up in the relevant clinical trials, the rates of serious adverse events such as stroke, heart attack and death were similar for patients treated with different anti-VEGF drugs. Moreover the arterial thrombotic risk appears sufficiently low when compared with the natural incidence of arterial thrombotic events in this category of elderly patients and acceptably balanced against the advantage of improved vision. Since the use of these drugs is likely to become increasingly widespread and prolonged, it is desirable that the scientific community improves the pharmacovigilance program on all anti-VEGF drugs, expanding knowledge with studies that compares head to head all four compounds belonging to anti-VEGF armamentarium.

Incidence of choroidal neovascularization in the fellow eye in the comparison of age-related macular degeneration treatments trials

OBJECTIVE

To assess the influence of drug; dosing regimen; and traditional, nontraditional, and genetic risk factors on the incidence of choroidal neovascularization (CNV) in the fellow eye of patients treated for CNV with ranibizumab or bevacizumab.

DESIGN

Cohort study of patients enrolled in a multicenter, randomized clinical trial.

PARTICIPANTS

Patients with no CNV in the fellow eye at the time of enrollment in the Comparison of Age-Related Macular Degeneration Treatments Trials (CATT).

METHODS

Eligibility criteria for the clinical trial required that study eyes have evidence on fluorescein angiography and optical coherence tomography of CNV secondary to age-related macular degeneration (AMD) and visual acuity between 20/25 and 20/320. Treatment for the study eye was assigned randomly to either ranibizumab or bevacizumab and to 3 different regimens for dosing over a 2-year period. The genotypes for 4 single nucleotide polymorphisms (SNPs) associated with risk of AMD were determined. Only patients without CNV in the fellow eye at baseline were considered at risk. The CATT ophthalmologists examined patients every 4 weeks through 2 years and recorded treatment for CNV in the fellow eye.

MAIN OUTCOME MEASURES

Development of CNV in the fellow eye.

RESULTS

Among 1185 CATT participants, 727 (61%) had no CNV in the fellow eye at enrollment. At 2 years, CNV had developed in 75 (20.6%) of 365 patients treated with ranibizumab and in 60 (16.6%) of 362 patients treated with bevacizumab (absolute difference, 4.0%; 95% confidence interval [CI], -1.7% to 9.6%; P = 0.17). The risk ratio for pro re nata dosing relative to monthly dosing was 1.1 (95% CI, 0.8-1.6). Greater elevation of the retinal pigment epithelium and fluid in the foveal center of the study eye were associated with increased incidence of CNV in the fellow eye. Incidence was not associated with genotype on rs1061170 (CFH), rs10490924 (ARMS2), rs11200638 (HTRA1), and rs2230199 (C3; P>0.35).

CONCLUSIONS

Through 2 years, there was no statistically significant difference between ranibizumab and bevacizumab in incidence of CNV in the fellow eye. Genotype on 4 SNPs previously found to be associated with AMD did not affect the risk of CNV in the fellow eye among CATT patients.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

An evidence-based review of vascular endothelial growth factor inhibition in pediatric retinal diseases: part 2. Coats' disease, best disease, and uveitis with childhood neovascularization

Vascular endothelial growth factor (VEGF) is an important factor in the pathogenesis of multiple retinal neovascular disorders. This report focuses on the quality and depth of new evidence for the use of VEGF inhibitors in selected pediatric ocular diseases, including Coats' disease, Best disease, and childhood uveitis. Because much of the literature comprises case reports and retrospective case series, the level of evidence supporting its use as a primary treatment option, or even as adjuvant therapy, is low. The standard of care is treatment of the underlying disorder to prevent neovascularization (retinal or subretinal), vitreous hemorrhage, or subsequent retinal detachment. However, these complications may not present until late in the disease course. It may then be useful to treat with these agents. Prospective studies are warranted to further elucidate the role of anti-VEGF therapy in these diseases.

Comparison of systemic adverse events associated with intravitreal anti-VEGF injection: ranibizumab versus bevacizumab

The aim of this study was to compare the incidence of systemic adverse events in patients treated with intravitreal injections of bevacizumab or ranibizumab, and to evaluate whether compared to ranibizumab administration, bevacizumab constitutes a higher risk for systemic adverse events. A retrospective review was conducted for 916 consecutive patients treated with at least 1 intravitreal injection of bevacizumab or ranibizumab. Cox regression was performed to assess whether a variable had predictive value for occurrence of new systemic adverse events and to account for different follow-up times. A total of 702 patients were analyzed; 503 patients received bevacizumab alone, and 199 patients received ranibizumab alone. Systemic adverse events occurred in 10 of 702 patients (1.4%): 7 in the bevacizumab group (7/503; 1.4%) and 3 in the ranibizumab group (3/199; 1.5%). This difference was not statistically significant (Fisher's exact test, P = 0.573). Cox proportional hazards analysis of 4 models did not reveal a covariate that significantly changed the hazard for systemic adverse events. In conclusion, compared to ranibizumab, bevacizumab may not increase the risk of systemic adverse events in patients receiving intravitreal injections.

An evidence-based meta-analysis of vascular endothelial growth factor inhibition in pediatric retinal diseases: part 1. Retinopathy of prematurity

Recently there has been interest in the novel, off-label use of anti-vascular endothelial growth factor (anti-VEGF) agents for various stages of retinopathy of prematurity (ROP). The authors report on the quality and depth of new evidence published from 2009 to 2011 concerning the treatment of retinopathy of prematurity (ROP) with bevacizumab (Avastin; Genentech Inc., South San Francisco, CA) as either primary or adjunctive treatment for ROP. There is significant variability in the evidence, quality, and design of the studies available in the literature. There has been a trend in the scientific literature of the past 2 years toward larger, multi-center, randomized studies investigating the role of bevacizumab in the treatment of ROP. More recent evidence suggests that monotherapy with intravitreal bevacizumab may be a viable first-line treatment for select cases of zone I ROP and possibly for posterior zone II disease. Adjunctive treatment with bevacizumab may enhance outcomes in patients treated with laser photocoagulation or pars plana vitrectomy. However, there are significant concerns regarding its long-term safety profile. Further prospective studies are warranted to more fully determine the role of anti-VEGF therapy in this disease.

Concentrations of unbound bevacizumab in the aqueous of untreated fellow eyes after a single intravitreal injection in humans

PURPOSE

To determine the concentration of unbound bevacizumab in untreated fellow eyes after contralateral intravitreal injection of bevacizumab.

METHODS

A total of 18 eyes received intravitreal injections of 1.5 mg bevacizumab. Nine probes were obtained in the injected eye and nine in the fellow eye. Each group contained three individual eyes. Aqueous humour samples were obtained during uneventful phacoemulsification at three intervals 1-7 days (group a), 8-12 days (group b) or 13-28 days (group c).

RESULTS

In untreated fellow eyes, the concentration of unbound bevacizumab was below the detectable limit of the ELISA (5 ng/ml in all samples). The mean concentration of unbound bevacizumab in the injected eye declined from 28.6 μg/ml (group a), 16.5 μg/ml (group b) to 7.4 μg/ml (group c).

CONCLUSIONS

There are no pharmacological indications for a significant concentration of unbound bevacizumab in the anterior chamber of contralateral eyes in humans.

The effect of intravitreal bevacizumab (Avastin) injection on retinal blood flow velocity in patients with choroidal neovascularization

Purpose

To study the short-term effects of intravitreal bevacizumab (Avastin) on retinal blood flow velocity and compare them to clinical outcomes assessed by optical coherence tomography (OCT) and tests of visual acuity.

Methods

The Retinal Function Imager (RFI) was used noninvasively and quantitatively to measure retinal blood flow velocity. Eight patients receiving intravitreal injection of Avastin for choroidal neovascularization (CNV) were included in this study. All were imaged by the RFI preinjection and 1 and 7 days postinjection. Visual acuity (VA) and OCT were recorded preinjection and 1 month postinjection. Comparisons were performed using paired Student t test and correlation using Spearman rank test.

Results

A good correlation was found between the 1-month change in VA and OCT measurements and the short-term change induced in blood flow velocity. Arterial and venous velocity changes 1 day after the injection correlated with the VA change (p<0.05). The 1-day arterial velocity changes correlated with total macular volume (p=0.02) and venous velocity changes correlated to central macular thickness (p=0.04).

Conclusions

The RFI provides a noninvasive technique to assess early hemodynamic responses to intravitreal injection of Avastin. These early changes may prove important for better understanding of the mechanism underlying this treatment and serve as a quantitative marker for treatment optimization.

Identifying systemic safety signals following intravitreal bevacizumab: systematic review of the literature and the Canadian Adverse Drug Reaction Database

OBJECTIVE

As the off-label use of intravitreal bevacizumab continues for an increasing number of ocular conditions, a systematic review of the literature aimed at detecting temporally associated systemic adverse events was undertaken.

DESIGN

Systematic review of the literature and a health regulatory database.

PARTICIPANTS

A total of 22 different clinical studies representing 12,699 patients.

METHODS

A systematic review indexed by Ovid MEDLINE, EMBASE, ISI Web of Science, the Cochrane database (CENTRAL), and the Canadian Adverse Drug Reaction Information System Database was performed. All clinical studies with at least 100 eyes injected with bevacizumab and case reports documenting suspected events were included for review.

RESULTS

A total of 22 different clinical studies were reviewed, including an international internet survey, 6 retrospective studies assessing the safety of intravitreal bevacizumab, and 15 clinical trials. The most common adverse systemic event reported in these studies, representing 12,699 patients was an increase in blood pressure (0.46% of patients), followed by cerebrovascular accidents (0.21% of patients), and myocardial infarction (0.19% of patients). The 6 case reports documented suspected events not previously identified and only 1 systemic event from the Health Canada database was retrieved.

CONCLUSIONS

The systemic events temporally associated with intravitreal bevacizumab are mainly of cardiovascular and neurological origin and can be predicted from an exaggerated pharmacology, although a causal association cannot be established at this time. Health Canada's spontaneous drug reporting system is an underutilized resource and a more active surveillance system such as a patient registry may be better suited to establish the low rates of systemic adverse events following bevacizumab use in ophthalmology.

Off-label use of bevacizumab for the treatment of age-related macular degeneration: what is the evidence?

There is an active and controversial debate about the role of intravitreal bevacizumab versus approved drugs in the treatment of neovascular age-related macular degeneration (AMD). Because bevacizumab was available prior to the launch of ranibizumab, off-label use of the former became widespread and the cancer drug bevacizumab is the most commonly used medication in ophthalmology nowadays. This review considers every publication identified in MEDLINE using the keywords 'bevacizumab' and 'Avastin' between 1 June 2005 and 31 July 2008. The search identified 511 papers that were evaluated. In 33 studies, there was consistent and clear evidence for the efficacy of bevacizumab in neovascular AMD. However, the highest grade studies (three prospective, randomized, controlled trials) did not attain better than grade 2b level of evidence, and objective evaluation of the benefit of bevacizumab relative to representative controls was therefore not possible. Certainly, the available evidence is inferior to that obtained from the approval studies of ranibizumab and this should influence treatment selection and guidance of patients. These considerations indicate that important quality criteria need to be included in future studies to ensure more meaningful conclusions can be drawn. These include clearly defined inclusion criteria, information about the recruitment procedure (including data on withdrawals, excluded patients, concealed treatment allocation, use of intention-to-treat analyses and blinded assessment procedures). Although preclinical studies have almost exclusively found bevacizumab to be safe, the design utilized in clinical case series cannot rule out a possible increase in adverse events, which already show a high spontaneous incidence in elderly AMD patients. The superior evidence level for ranibizumab and the limited safety data for bevacizumab must be taken into consideration when evaluating the costs that a healthcare system is willing to spend. However, the superior grade of evidence for ranibizumab should not be confused with the (still missing) evidence for superior efficacy. The results of ongoing randomized, controlled, comparative trials will provide further data on the efficacy and cost effectiveness of bevacizumab and ranibizumab in the treatment of AMD. In the meantime, patients should be informed about the alternatives, the price differences and the restricted liability issue when off-label use of bevacizumab is offered.