Serum concentrations of bevacizumab (avastin) and vascular endothelial growth factor in infants with retinopathy of prematurity

Circulating VEGF-A Levels in Relation to Retinopathy of Prematurity and Treatment Effects: A Systematic Review and Meta-Analysis

Topic

Retinopathy of prematurity (ROP) is a severe retinal vascular disorder affecting preterm infants, potentially leading to retinal detachment and blindness. This review aims to elucidate the relationship between systemic VEGF levels and ROP.

Clinical Relevance

This systematic review aims to consolidate evidence from available studies to guide future research and inform clinical practice. In particular, the role of circulating VEGF-A levels in predicting ROP onset and progression, and evaluating the impact of anti-VEGF therapy on these levels, is crucial in ensuring efficacy and safety in patient care.

Methods

Scopus and PubMed were searched to identify studies investigating circulating VEGF-gene products in ROP patients using immunologic assays. Two authors independently screened the literature and extracted data, employing a random-effects meta-analysis to compare VEGF levels as the ratio of means between ROP patients and controls before and after treatment, heterogeneity was reported by I2-statistics. Risks of bias and publication bias were assessed using Quality Assessment of Diagnostic Accuracy Studies-2 and funnel plots/Egger's tests, respectively.

Results

Out of 941 papers, 54 were included, with 26 providing posttreatment data and 31 providing biomarker data. Findings show a significant decrease in VEGF-A levels in the first week after ROP treatment (ratio of means [95% confidence interval] 0.34 [0.25-0.45], I2 = 97%, 17 publications). Anti-VEGF therapy showed a significantly more pronounced decrease (0.31 [0.25-0.38], I2 = 40%, 7 publications) than laser treatment in the first week after treatment (0.77 [0.61-0.97], I2 = 42%, 2 publications, subgroup difference, P < 0.01), among studies with a low risk of bias. Serum samples demonstrated a more marked decrease in VEGF-A than plasma (subgroup difference P < 0.01). However, the use of blood VEGF-A concentration as a biomarker for ROP prediction has shown inconsistent trends. The risk of bias mainly stems from unclear patient selection and lack of sample timing or analytical method details.

Conclusion

While anti-VEGF treatment significantly reduced blood VEGF-A levels in the first week post-ROP treatment, blood VEGF-A levels did not consistently predict ROP development. Heterogeneity in the results underscores the need for optimized analytical methods and emphasizes the importance of considering individual variation in VEGF-A concentrations independent of ROP diagnosis.

Financial Disclosures

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Mitochondrial control of hypoxia-induced pathological retinal angiogenesis

OBJECTIVE

Pathological retinal neovascularization is vision-threatening. In mouse oxygen-induced retinopathy (OIR) we sought to define mitochondrial respiration changes longitudinally during hyperoxia-induced vessel loss and hypoxia-induced neovascularization, and to test interventions addressing those changes to prevent neovascularization.

METHODS

OIR was induced in C57BL/6J mice and retinal vasculature was examined at maximum neovessel formation. We assessed total proteome changes and the ratio of mitochondrial to nuclear DNA copy numbers (mtDNA/nDNA) of OIR vs. control retinas, and mitochondrial oxygen consumption rates (OCR) in ex vivo OIR vs. control retinas (BaroFuse). Pyruvate vs. vehicle control was supplemented to OIR mice either prior to or during neovessel formation.

RESULTS

In OIR vs. control retinas, global proteomics showed decreased retinal mitochondrial respiration at peak neovascularization. OCR and mtDNA/nDNA were also decreased at peak neovascularization suggesting impaired mitochondrial respiration. In vivo pyruvate administration during but not prior to neovessel formation (in line with mitochondrial activity time course) suppressed NV.

CONCLUSIONS

Mitochondrial energetics were suppressed during retinal NV in OIR. Appropriately timed supplementation of pyruvate may be a novel approach in neovascular retinal diseases.

Relations between Neurocognitive Function and Visual Acuity: A Cross-Sessional Study in a Cohort of Premature Children

BACKGROUND

Premature children with retinopathy of prematurity (ROP) have been reported to an have increased risk of visual and neurocognitive impairments, yet little is known about whether vision could affect specific neurocognition. This study aimed to clarify the correlations between neurocognition and vision in premature children.

MATERIALS AND METHODS

This is a nonrandomized, cross-sectional, observational study in a pediatric cohort with five groups: (1) full-term (n = 25), (2) prematurity without ROP (n = 154), (3) prematurity with ROP but without treatment (n = 39), (4) prematurity with ROP and with bevacizumab (IVB) treatment (n = 62), and (5) prematurity with ROP and with laser/laser + IVB treatment (n = 20). Neurocognitive function was evaluated by the Wechsler Preschool and Primary Scale of Intelligence, Fourth Edition (WPPSI-IV) around the age of 4 years. Visual acuity (VA) and refractive errors were tested. Correlations between WPPSI parameters and visual outcomes were analyzed across five groups.

RESULTS

Among the 300 recruited children (mean age = 4.02 + 0.97 years, male = 56.3%), 297 were assessed by WPPSI-IV and 142 were assessed by vision tests. The Full-Scale Intelligence Quotient (FSIQ) index was worse in the premature groups. After adjusting for covariates, seven items, including FSIQ-Index (p = 0.047), fluid-reasoning index (p = 0.004), FR-percentile ranking (p = 0.008), object assembly (p = 0.034), picture concept (p = 0.034), zoo locations (p = 0.014) and bug search (p = 0.020), showed significant differences between groups. The better the best corrected VA (BCVA), the higher the scores on Verbal Comprehension Index (VCI), VCI-PR, and the subtest of information.

CONCLUSIONS

Specific cognitive dysfunctions are related to the BCVA in this large cohort. Subtest performance profiles in WPPSI can be affected by prematurity, ROP treatment, and different ROP treatment. FSIQ is generally lower in premature children and even lower in children with ROP.

Timed topical dexamethasone eye drops improve mitochondrial function to prevent severe retinopathy of prematurity

Pathological neovascularization in retinopathy of prematurity (ROP) can cause visual impairment in preterm infants. Current ROP treatments which are not preventative and only address late neovascular ROP, are costly and can lead to severe complications. We showed that topical 0.1% dexamethasone eye drops administered prior to peak neovessel formation prevented neovascularization in five extremely preterm infants at high risk for ROP and suppressed neovascularization by 30% in mouse oxygen-induced retinopathy (OIR) modeling ROP. In contrast, in OIR, topical dexamethasone treatment before any neovessel formation had limited efficacy in preventing later neovascularization, while treatment after peak neovessel formation had a non-statistically significant trend to exacerbating disease. Optimally timed topical dexamethasone suppression of neovascularization in OIR was associated with increased retinal mitochondrial gene expression and decreased inflammatory marker expression, predominantly found in immune cells. Blocking mitochondrial ATP synthetase reversed the inhibitory effect of dexamethasone on neovascularization in OIR. This study provides new insights into topical steroid effects in retinal neovascularization and into mitochondrial function in phase II ROP, and suggests a simple clinical approach to prevent severe ROP.

Aflibercept to treat retinopathy of prematurity: need for more research

Until recently, the standard care for retinopathy of prematurity (ROP) was destructive treatment of the peripheral avascular retina, most often using laser therapy. Now, intravitreal anti-vascular endothelial growth factor (anti-VEGF) agents have been included in recommendations for treatment-warranted ROP. The three anti-VEGF agents used to treat ROP are bevacizumab, ranibizumab, and aflibercept and clinical trials using, a variety of treatment strategies, have shown all three are efficacious and easy to administer. Intravitreal Bevacizumab is most used in the US, and ranibizumab has been approved for ROP use in Europe. In 2023, the FDA approved aflibercept for treatment of severe ROP. We summarize the clinical trial results and provide a side-by-side comparisons of the three drugs. Despite FDA approval of the use of aflibercept to treat ROP, there is a need for more research as the body of knowledge regarding this agent to treat ROP is limited.

A Narrative Review on Managing Retinopathy of Prematurity: Insights Into Pathogenesis, Screening, and Treatment Strategies

Retinopathy of prematurity (ROP) is a rare proliferative ocular condition that can happen in premature babies (born preterm <36 weeks) or who weigh <1.5 kg at birth (low birth weight babies). ROP is a major cause of childhood blindness. It is a premature disease since retina vascularization is completed only by 40 weeks of life. The survivability for preterm infants has increased owing to recent improvements in neonatal care during the past decade. As a result, the prevalence of ROP has risen concurrently. The abnormal development of blood vessels in the retina is the cause of this illness. It occurs in two phases, phases 1 and 2. Most preterm infants weighing <1.5 kg need supplemental oxygen for respiratory support at birth. This leads to the initiation of phase 1 (vasoconstrictive phase). Phase 1 is characterized by loss of maternal-fetal connection and hyperoxia due to supplemental oxygen therapy. Oxygen's vasoconstrictive and obliterative action is primarily observed in developing retinal vessels. The inhibition of vascular endothelial growth factor follows from this. Phase 2 (vasoproliferative phase) shows the dilatation and tortuosity of the bigger existing vessels together with neovascularization and proliferation of new vessels into the vitreous when the baby is shifted from respiratory support to room air. Now, the retina gets hypoxic, where the retina becomes more metabolically active but is yet minimally vascularized, leading to VEGF-induced vasoproliferation, which might result in retinal detachment. Patients with ROP face the danger of loss of vision. If correct and quick treatment is not provided, they might land into permanent blindness. Yet, ROP remains one of the most preventable causes of childhood blindness worldwide. Blindness caused by ROP can only be avoided if screening programs are readily available, pertinent, and appropriate. The initial stage in the therapy of ROP is the screening of premature neonates. Timely screening and management for ROP is important to avoid this irreversible loss of vision. The treatment is based on the severity of the disease. Management may include pharmacological interventions like intravitreal and anti-vascular endothelial growth factor and non-pharmacological interventions like laser surgery, vitrectomy, and scleral buckling. We conducted a thorough literature search of studies on pathogenesis, risk factors, classification, and various treatment options for retinopathy of prematurity in infants, using a mixture of pertinent keywords. Only those studies published in peer-reviewed journals between 2010 and 2023 and written in English were included. Duplicate studies, unavailable in full-text for free, or studies unrelated to our subject matter were excluded. After thoroughly evaluating the selected studies, the results were synthesized and presented narratively. This article sheds light on the pathogenesis of ROP, particularly its relation to oxygen use, screening, and potential therapeutic management of ROP. Today advances in screening techniques have improved the outcomes for infants with ROP. Still, ongoing research is needed to optimize management strategies and reduce the burden of this condition.

Targeting the Mitochondrial Chaperone TRAP1 Alleviates Vascular Pathologies in Ischemic Retinopathy

Activation of hypoxia-inducible factor 1α (HIF1α) contributes to blood-retinal barrier (BRB) breakdown and pathological neovascularization responsible for vision loss in ischemic retinal diseases. During disease progression, mitochondrial biology is altered to adapt to the ischemic environment created by initial vascular dysfunction, but the mitochondrial adaptive mechanisms, which ultimately contribute to the pathogenesis of ischemic retinopathy, remain incompletely understood. In the present study, it is identified that expression of mitochondrial chaperone tumor necrosis factor receptor-associated protein 1 (TRAP1) is essential for BRB breakdown and pathologic retinal neovascularization in mouse models mimicking ischemic retinopathies. Genetic Trap1 ablation or treatment with small molecule TRAP1 inhibitors, such as mitoquinone (MitoQ) and SB-U015, alleviate retinal pathologies via proteolytic HIF1α degradation, which is mediated by opening of the mitochondrial permeability transition pore and activation of calcium-dependent protease calpain-1. These findings suggest that TRAP1 can be a promising target for the development of new treatments against ischemic retinopathy, such as retinopathy of prematurity and proliferative diabetic retinopathy.

Respiratory outcomes in preterm infants following intravitreal bevacizumab for retinopathy of prematurity-a 10-year matched case study

OBJECTIVES

To evaluate respiratory outcomes in preterm infants with retinopathy of prematurity (ROP) following intravitreal bevacizumab injection (IVB).

METHODS

This single-centre study enroled preterm infants with a gestational age (GA) < 34 weeks or a birth weight (BW) < 1500 g with bilateral type 1 ROP who received a single IVB, and a treatment-free control group matched by GA, postmenstrual age, and respiratory status at the time of the IVB. The primary outcome was serial respiratory changes in mean airway pressure (MAP), fraction of inspired oxygen (FiO2), and respiratory severity score (RSS, MAP x FiO2) during the 28-day post-IVB/matching period and overall respiratory improvement at day 28 and at discharge. The duration of supplemental oxygen therapy following IVB/matching was documented.

RESULTS

A total of 5578 infants were included. Seventy-eight infants were enroled in the IVB group, and another 78 infants were matched as the control group. Both groups had downward trends in the MAP, FiO2, and RSS over the study period (all P < 0.001), but there were no between-group differences in these measures. The percentage of overall respiratory improvement was similar between the IVB and control groups, so was the duration of invasive and in-hospital oxygen ventilation. A lower percentage of oxygen dependence at discharge in the IVB group (P = 0.03) remained significant after adjusting for GA and BW.

CONCLUSIONS

This is a matched case study to evaluate respiratory outcomes in preterm infants following IVB for ROP. We found that the IVBs did not compromise respiratory outcomes in preterm infants during the 28-day post-IVB period and at discharge.

Postnatal hyperglycemia alters amino acid profile in retinas (model of Phase I ROP)

Nutritional deprivation occurring in most preterm infants postnatally can induce hyperglycemia, a significant and independent risk factor for suppressing physiological retinal vascularization (Phase I retinopathy of prematurity (ROP)), leading to compensatory but pathological neovascularization. Amino acid supplementation reduces retinal neovascularization in mice. Little is known about amino acid contribution to Phase I ROP. In mice modeling hyperglycemia-associated Phase I ROP, we found significant changes in retinal amino acids (including most decreased L-leucine, L-isoleucine, and L-valine). Parenteral L-isoleucine suppressed physiological retinal vascularization. In premature infants, severe ROP was associated with a higher mean intake of parenteral versus enteral amino acids in the first two weeks of life after adjustment for treatment group, gestational age at birth, birth weight, and sex. The number of days with parenteral amino acids support independently predicted severe ROP. Further understanding and modulating amino acids may help improve nutritional intervention and prevent Phase I ROP.

Laser versus Anti-VEGF: A Paradigm Shift for Treatment-Warranted Retinopathy of Prematurity

Retinopathy of prematurity (ROP), a leading cause of childhood blindness, has historically been associated with blindness from overgrowth of blood vessels from the retina into the vitreous that lead to complex retinal detachments. Our understanding of ROP has evolved with the survival of extremely low-birthweight infants and includes not only overgrowth of blood vessels, but also insufficient developmental retinal vascular growth in early phases of the disease. Our current treatments of ROP have focused on methods to improve perinatal and prenatal care, reduce premature birth, and prevent early phases of ROP. Nonetheless, addressing vasoproliferation in treatment-warranted eyes remains the mainstay of management. Two main treatment strategies co-exist today: laser treatment, which has been the standard of care since the 1990s, and anti-VEGF injections, which have been used since early reports in 2007 (Travassos et al. in Ophthalmic Surg Lasers Imaging, 38:233-237, https://doi.org/10.3928/15428877-20070501-09 , 2007, Shah et al. in Indian J Ophthalmol 55:75-76, https://doi.org/10.4103/0301-4738.29505 , 2007, Quiroz-Mercado et al. in Semin Ophthalmol 22:109-125, https://doi.org/10.1080/08820530701420082 , 2007).

Retinopathy of prematurity: from oxygen management to molecular manipulation

INTRODUCTION

Retinopathy of prematurity (ROP) is a vasoproliferative disorder of the premature retina with the potential to progress to extraretinal neovascularisation. This review serves as an introduction to retinopathy of prematurity (ROP), outlining key parts of ROP pathophysiology, diagnosis and treatment. ROP is traditionally diagnosed by indirect ophthalmoscopy and classified using anatomical zones, stages of disease, and the presence or absence of "plus disease" (dilation and tortuosity of the major retinal arterioles and venules). ROP has a bi-phasic pathophysiology: initial hyperoxia causes reduced retinal vascularisation, followed by pathological vaso-proliferation resulting from subsequent hypoxia and driven by vascular endothelial growth factor (VEGF).

ADVANCEMENTS IN MANAGEMENT

This review summarises previous trials to establish optimum oxygen exposure levels in newborns and more recently the development of anti-VEGF agents locally delivered to block pathological neovascularisation, which is technically easier to administer and less destructive than laser treatment.

FUTURE DIRECTIONS

There remains an ongoing concern regarding the potential unwanted systemic effects of intravitreally administered anti-VEGF on the overall development of the premature baby. Ongoing dosing studies may lessen these fears by identifying the minimally effective dose required to block extraretinal neovascularisation.

Electroretinographic Responses in Retinopathy of Prematurity Treated Using Intravitreal Bevacizumab or Laser

PURPOSE

Intravitreal injection of bevacizumab (IVB) offers advantages over laser photoablation for treatment of type 1 retinopathy of prematurity (ROP). However, retinal function has not, to date, been quantitatively compared following these interventions. Therefore, electroretinography (ERG) was used compare retinal function among eyes treated using IVB or laser, and control eyes. In addition, among the IVB-treated eyes, ERG was used to compare function in individuals in whom subsequent laser was and was not required.

DESIGN

Prospective clinical cohort study.

METHODS

ERG was used to record dark- and light-adapted stimulus/response functions in 21 children treated using IVB (12 of whom required subsequent laser in at least 1 eye for persistent avascular retina [PAR]). Sensitivity and amplitude parameters were derived from the a-wave, b-wave, and oscillatory potentials (OPs), representing activity in photoreceptor, postreceptor, and inner retinal cells, respectively. These parameters were then referenced to those of 76 healthy, term-born controls and compared to those of 10 children treated using laser only.

RESULTS

In children with treated ROP, every ERG parameter was significantly below the mean in controls. However, these significant ERG deficits did not differ between IVB- and laser-treated eyes. Among children treated using IVB, no ERG parameter was significantly associated with dose or need for subsequent laser.

CONCLUSION

Retinal function was significantly impaired in treated ROP eyes. Function in IVB-treated eyes did not differ from that in laser-treated eyes. Functional differences also did not distinguish those IVB-treated eyes that would subsequently need laser for PAR.

A Meta-Analysis of Neurodevelopmental Outcomes following Intravitreal Bevacizumab for the Treatment of Retinopathy of Prematurity

BACKGROUND

Retinopathy of prematurity (ROP) is the most common cause of preventable blindness in preterm infants. First-line treatments include intravitreal bevacizumab (IVB) or laser photocoagulation (LPC).

OBJECTIVES

The aim of the study was to evaluate neurodevelopmental safety of IVB compared to LPC for ROP.

METHODS

MEDLINE, Embase, and Cochrane library were searched up to September 2022. Studies were included with at least 12-month follow-up of primary outcomes such as severe neurodevelopmental impairment (sNDI), cerebral palsy (CP), and hearing impairment (HI). Secondary outcomes were moderate-to-severe neurodevelopmental impairment (msNDI), Bayley Scores of Infant Development (BSID-III), and visual impairment.

RESULTS

1,231 patients from 11 comparative studies were included. Quality of evidence was rated low for all outcomes. IVB was associated with a higher risk for sNDI (risk ratio [RR] = 1.25, 95% confidence interval [CI]: [1.01, 1.53], p = 0.04); and CP (RR = 1.40, CI: [1.08, 1.81], p = 0.01) compared to LPC. There was no significant difference between IVB and LPC for msNDI (RR = 1.15, CI: [0.98, 1.35], p = 0.08) and HI (RR = 1.43, CI: [0.86, 2.39], p = 0.17). BSID-III percentile scores were similar between IVB and LPC, with weighted mean differences of 1.51 [CI = -1.25, 4.27], 2.43 [CI = -1.36, 6.22], and 1.97 [CI = -1.06, 5.01] for cognitive, language, and motor domains, respectively (p > 0.05).

CONCLUSION

To our knowledge, this is the largest meta-analysis on neurodevelopmental outcomes and the first to rigorously examine IVB monotherapy in ROP treatment. Compared to LPC, there was a marginally increased risk for sNDI and CP with IVB but little or no difference in the risk of msNDI and HI. Further randomized studies are needed to strengthen these findings.

Comparison of Bevacizumab and Aflibercept for Suppression of Angiogenesis in Human Retinal Microvascular Endothelial Cells

Bevacizumab (Avastin) is a vascular endothelial growth factor (VEGF) inhibitor that is widely used for aggressive posterior retinopathy of prematurity (APROP). Its use is associated with multiple adverse effects. Aflibercept (Eylea) is a VEGFR-1 analogue that is approved for ocular use, but its efficacy for APROP is less studied. We tested the hypothesis that Eylea is as effective as Avastin for suppression of intermittent hypoxia (IH)-induced angiogenesis. Human retinal microvascular endothelial cells (HRECs) were treated with Avastin and low- or high-dose Eylea and exposed to normoxia, hyperoxia (50% O₂), or neonatal IH for 24, 48, or 72 h. Cells were assessed for migration and tube formation capacities, as well as biomarkers of angiogenesis and oxidative stress. Both doses of Eylea suppressed migration and tube formation in all oxygen environments, although the effect was not as robust as Avastin. Furthermore, the lower dose of Eylea appeared to be more effective than the higher dose. Eylea induced soluble VEGFR-1 (sVEGFR-1) coincident with high IGF-I levels and decreased Notch/Jagged-1, demonstrating a functional association. Given the role of VEGFR-1 and Notch as guidance cues for vascular sprouting, these data suggest that Eylea may promote normal vascular patterning in a dose-dependent manner.

Neurodevelopmental Outcomes for Retinopathy of Prematurity: A Taiwan Premature Infant Follow-up Network Database Study

PURPOSE

To evaluate the neurodevelopmental outcomes in premature infants who received intravitreal anti-vascular endothelial growth factor (anti-VEGF) injections to treat retinopathy of prematurity (ROP).

DESIGN

Retrospective cohort study.

METHODS

This study was conducted using the database from the Taiwan Premature Infant Follow-up Network. Demographic data, systemic risk factors, ROP status, and neurodevelopmental assessment using the Bayley Scales of Infant and Toddler Development, Third Edition (Bayley-III) were collected. Patients were divided into 4 groups: prematurity without ROP, ROP without treatment, ROP with laser treatment, and ROP with intravitreal anti-VEGF treatment. A generalized estimating equation was used for analyzing repeated measurements of Bayley-III at the corrected ages of 6, 12, and 24 months.

RESULTS

A total of 2090 patients with a mean gestational age of 31.2 weeks were included. The Bayley-III composite scores of patients with ROP treated with anti-VEGF were comparable to those of patients with ROP without treatment (cognitive: P = .491; language: P = .201; motor: P = .151) and premature patients without ROP (cognitive: P = .985; language: P = .452; motor: P = .169) after adjusting for confounders. Patients with ROP treated with laser photocoagulation exhibited poorer cognitive composite scores than did those without treatment (P < .001), premature patients without ROP (P < .001), and those treated with anti-VEGF (P < .001), but they had similar language and motor composite scores.

CONCLUSIONS

Intravitreal anti-VEGF treatment for ROP was not associated with adverse neurodevelopment in premature infants. Further studies are needed to determine whether general anesthesia or sedation used in laser treatment for ROP has significant impacts on neurodevelopmental outcomes.

Role of Anti-Vascular Endothelial Growth Factor (Anti-VEGF) in the Treatment of Retinopathy of Prematurity: A Narrative Review in the Context of Middle-Income Countries

The rise in preterm births and higher survival rates of premature infants have led to a global increase in retinopathy of prematurity (ROP), a vasoproliferative retinal disorder common in premature infants. ROP is one of the leading causes of childhood blindness. Clinical manifestation of ROP ranges from mild abnormal retinal neovascularization to bilateral retinal detachment and vision loss. The incidence of ROP is higher in middle income countries, including India, which has the highest number of global preterm births. Low birth weight and low gestational age are the primary risk factors for ROP; however, anemia, cardiac defects, blood transfusion, apnea, sepsis, respiratory distress syndrome, high exposure to oxygen and poor postnatal weight gain may also contribute to its development. India has stringent ROP screening guidelines revised in 2018, and screening of infants with either birth weight <2000 grams or gestational age <34 weeks is mandated. With an improved understanding of the pathogenesis of ROP in the past decades and advances in clinical research, treatment for ROP has evolved from cryotherapy to laser retinal ablation. Most recently, anti-vascular endothelial growth factor (anti-VEGF) drugs have emerged as a favorable treatment option for zone-I and II ROP. This article reviews the current approaches for ROP treatment in India with a particular focus on anti-VEGF drugs. The article also integrates the understanding of safety and risk-benefit evaluation of the current approaches in ROP management. The review concluded that there is a need to increase the ROP screening not only for preterm and low birth weight but also for optimal gestational age infants with healthy birth weight. Anti-VEGF therapies have shown improved efficacy, although studies are required to establish the long-term safety.

Long-Term Visual Prognosis of Patients Following Lens-Sparing Vitrectomy for Stage 4A Retinopathy of Prematurity

This study evaluated the long-term visual outcomes of patients in whom at least one eye underwent successful lens-sparing vitrectomy (LSV) for stage 4A retinopathy of prematurity (ROP). A retrospective chart review was conducted using the data of 61 eyes of 42 patients with a minimum 4-year follow-up after successful LSV, with or without anti-vascular endothelial growth factor (VEGF) therapy, and whose best-corrected visual acuity (BCVA) was measurable using Landolt rings at the final visit. The mean age at the final follow-up was 10.1 ± 3.3 years. Before LSV, all eyes underwent laser ablation therapy. Twenty eyes (32.8%) with high vascular activity received anti-VEGF therapy before LSV. The mean decimal BCVA at the final follow-up was 0.23 ± 0.26 (range: hand motion to 1.2). Twenty-three eyes (54.1%) had a decimal BCVA of ≥0.4. Among 49 phakic eyes at the final examination, the mean refractive error was -10.1 ± 5.0 D, with 37 eyes (75.5%) having high myopia (>-6.0 D). No significant differences were observed in terms of decimal BCVA and refractive errors between eyes with and without anti-VEGF therapy. Approximately half of the patients had a decimal BCVA of ≥0.4, despite myopic refraction after successful LSV for stage 4A ROP. LSV for stage 4A ROP seemed to be associated with good visual function, despite myopic refraction.

Retinopathy of prematurity and neurodevelopmental outcomes in preterm infants: A systematic review and meta-analysis

Background

Retinopathy of prematurity (ROP) and abnormal brain development share similar risk factors and mechanisms. There has been contrasting evidence on the association of ROP with adverse neurodevelopmental outcomes.

Objective

We analysed the association between ROP at levels of severity and treatment with all neurodevelopmental outcomes until adolescence.

Data source

We followed PRISMA guidelines and searched Medline and Embase between 1 August 1990 and 31 March 2022.

Study selection and participants

Randomised or quasi-randomised clinical trials and observational studies on preterm infants (<37 weeks) with ROP [type 1 or severe ROP, type 2 or milder ROP, laser or anti-vascular endothelial growth factor (VEGF) treated] were included.

Data extraction and synthesis

We included studies on ROP and any neurocognitive or neuropsychiatric outcomes.

Outcomes

The primary outcomes were as follows: cognitive composite scores evaluated between the ages of 18 and 48 months by the Bayley Scales of Infant and Toddler Development (BSID) or equivalent; neurodevelopmental impairment (NDI; moderate to severe NDI or severe NDI), cerebral palsy, cognitive impairment; and neuropsychiatric or behavioural problems. The secondary outcomes were as follows: motor and language composite scores evaluated between the ages of 18 and 48 months by BSID or equivalent; motor/language impairment; and moderate/severe NDI as defined by the authors.

Results

In preterm infants, "any ROP" was associated with an increased risk of cognitive impairment or intellectual disability [n = 83,506; odds ratio (OR): 2.56; 95% CI: 1.40-4.69; p = 0.002], cerebral palsy (n = 3,706; OR: 2.26; 95% CI: 1.72-2.96; p < 0.001), behavioural problems (n = 81,439; OR: 2.45; 95% CI: 1.03-5.83; p = 0.04), or NDI as defined by authors (n = 1,930; OR: 3.83; 95% CI: 1.61-9.12; p = 0.002). Type 1 or severe ROP increased the risk of cerebral palsy (OR: 2.19; 95% CI: 1.23-3.88; p = 0.07), cognitive impairment or intellectual disability (n = 5,167; OR: 3.56; 95% CI: 2.6-4.86; p < 0.001), and behavioural problems (n = 5,500; OR: 2.76; 95% CI: 2.11-3.60; p < 0.001) more than type 2 ROP at 18-24 months. Infants treated with anti-VEGF had higher odds of moderate cognitive impairment than the laser surgery group if adjusted data (gestational age, sex severe intraventricular haemorrhage, bronchopulmonary dysplasia, sepsis, surgical necrotising enterocolitis, and maternal education) were analysed [adjusted OR (aOR): 1.93; 95% CI: 1.23-3.03; p = 0.04], but not for cerebral palsy (aOR: 1.29; 95% CI: 0.65-2.56; p = 0.45). All outcomes were adjudged with a "very low" certainty of evidence.

Conclusion and relevance

Infants with "any ROP" had higher risks of cognitive impairment or intellectual disability, cerebral palsy, and behavioural problems. Anti-VEGF treatment increased the risk of moderate cognitive impairment. These results support the association of ROP and anti-VEGF treatment with adverse neurodevelopmental outcomes.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/, identifier: CRD42022326009.

Applying Lucentis for the treatment of retinopathy of prematurity

Purpose: to evaluate the efficacy of Lucentis for the treatment of retinopathy of prematurity (ROP). Material and methods. 51 infants (102 eyes) with the gestational age between 24 and 33 weeks were given intravitreal injections of Lucentis, All patients selected had ROP stages I+, II+, III or III+ in zone 1, stage III+ in zone 2, or aggressive posterior ROP. The procedure was performed under general anesthesia; the dose, technique and the number of Lucentis injections conformed with the recommendations given in Lucentis instruction for use. If indicated, retinal laser photocoagulation was given after intravitreal injections using Supra (Quantel Medical, France) and Lachta-Mylon (Russia, Lasermedservis) laser equipment. Results. Clinical efficacy of intravitreal administration of Ranibizumab in infants with aggressive posterior ROP, zone 1 ROP, Stage III of zone 2 ROP was determined at 86.3 % (with no more than two injections). If ROP remains active after two injections, a change of therapy is recommended. Vascularization was noted to be complete in 51 % of cases. Conclusion. To achieve a maximum treatment effect of ROP with Lucentis, strict observation of indications criteria must take place.

Comparison of intravitreal injection of ranibizumab versus bevacizumab for treatment of type 1 and aggressive retinopathy of prematurity in rural Egypt. A randomized clinical trial

Objective

The objective of this study is to evaluate the efficacy of intravitreal ranibizumab (IVR) monotherapy compared with intravitreal bevacizumab (IVB) monotherapy for treatment of type 1 and aggressive retinopathy of prematurity (ROP) in rural Egypt.

Methods

36 eyes of 18 infants with bilateral aggressive or type 1 ROP were recruited between September 2020 and September 2022. Mean follow-up duration was 16.53 months. IVB was injected in the right eye and IVR in the left eye, rescue injection of the same initial anti-vascular endothelial growth factor (VEGF) in case of ROP reactivation. Outcome measures included regression achieved either by single injection or multiple injections or additional laser therapy at 55 weeks’ postmenstrual age (PMA), recurrence of ROP, total retinal vascularisation time and complications.

Results

Initial regression of ROP within 1 week occurred in 11/18 eyes (61.1%) in bevacizumab group and 15/18 eyes (83.3%) in ranibizumab group (p=0.137). Primary outcome measure was achieved in 14/18 eyes (77.8%) and 16/18 eyes (88.9%) in bevacizumab and ranibizumab groups, respectively (p=0.658). Late reactivation requiring retreatment with anti-VEGF was encountered in 4/18 eyes (22.2%) and 1/18 eyes (5.6%) in bevacizumab and ranibizumab groups, respectively (p=0.338). Peripheral laser therapy on the avascular retina was done in 3/18 eyes (16.7%) in each group at mean of 55.67 weeks' PMA.

Conclusion

Bevacizumab and ranibizumab proved to be effective regarding regression of acute ROP and continuing peripheral retinal vascularisation. Higher proportion of reactivation with bevacizumab, however, clinically non-significant. Laser therapy can be postponed to reduce its complications.

Trial registration number

NCT05033106.

A Network Meta-Analysis of Retreatment Rates following Bevacizumab, Ranibizumab, Aflibercept, and Laser for Retinopathy of Prematurity

TOPIC

To compare bevacizumab, ranibizumab, aflibercept, and laser treatment as primary therapies for retinopathy of prematurity (ROP) in terms of retreatment rate.

CLINICAL RELEVANCE

Anti-VEGF agents are increasingly used as primary treatment for ROP and may provide superior outcomes compared with laser in posterior disease. Head-to-head comparisons between different anti-VEGFs are lacking.

METHODS

We searched CENTRAL, Embase, MEDLINE, and CINAHL databases for randomized controlled trials and nonrandomized comparative studies that had been reported as of March 2022. We included studies that used bevacizumab, ranibizumab, aflibercept or laser for ROP with comparable cohorts and treatment criteria. Studies were evaluated by the Grading of Recommendations, Assessment, Development and Evaluation framework, and those with biased case selection, nonrandomized case-control, or lack of control group were excluded. Frequentist meta-analyses of proportions determined the absolute primary retreatment rate of each modality and Bayesian network meta-analyses compared pairs of treatments in type 1 and Zone I ROP.

RESULTS

In all, 30 studies (4686 eyes) were included in the network meta-analyses. For type 1 ROP, single-treatment success rates (i.e., likelihood of needing no further treatment) were 89.3% (95% confidence interval [CI]: 83.8%-93.8%; n = 1552) for laser, 87.0% (95% CI: 78.6%-93.8%; n = 2081) for bevacizumab, 80.7% (95% CI: 62.0%-94.4%; n = 326) for aflibercept, and 74.0% (95% CI: 62.7%-84.1%; n = 727) for ranibizumab. Bayesian network meta-analysis indicates that laser treatment is associated with a significant 62% (95% credible interval [CrI]: 16%-83%) reduction in retreatment risk compared with ranibizumab, while no significant difference was found among other pairwise comparisons. The mean ± standard error of the mean times to secondary treatment following primary aflibercept (12.96 ± 0.47 weeks) and bevacizumab (11.36 ± 0.54 weeks) therapy were significantly longer than that for primary ranibizumab (9.29 ± 0.43weeks) therapy (P = 7 × 10^-7 and P = 9 × 10^-3, respectively). For Zone I ROP, single-treatment success rates were 91.2% (95% CI: 83.6-96.9; n = 231) for bevacizumab, 78.3% (95% CI: 61.4-91.9; n = 100) for ranibizumab, and 65.9% (95% CI: 41.4-87.2; n = 158) for laser treatment. In this case, Bayesian network meta-analysis suggests that primary bevacizumab is associated with a significant 67% (95% CrI:10%-90%) reduction in retreatment risk compared with laser treatment.

CONCLUSIONS

Laser was associated with a lower rate of retreatment than ranibizumab in type 1 ROP (Zones I and II combined), while bevacizumab was associated with a lower rate of retreatment than laser in Zone I ROP. Aflibercept and bevacizumab demonstrate longer duration of action than ranibizumab for ROP.

Retinopathy of prematurity: Metabolic risk factors

At preterm birth, the retina is incompletely vascularized. Retinopathy of prematurity (ROP) is initiated by the postnatal suppression of physiological retinal vascular development that would normally occur in utero. As the neural retina slowly matures, increasing metabolic demand including in the peripheral avascular retina, leads to signals for compensatory but pathological neovascularization. Currently, only late neovascular ROP is treated. ROP could be prevented by promoting normal vascular growth. Early perinatal metabolic dysregulation is a strong but understudied risk factor for ROP and other long-term sequelae of preterm birth. We will discuss the metabolic and oxygen needs of retina, current treatments, and potential interventions to promote normal vessel growth including control of postnatal hyperglycemia, dyslipidemia and hyperoxia-induced retinal metabolic alterations. Early supplementation of missing nutrients and growth factors and control of supplemental oxygen promotes physiological retinal development. We will discuss the current knowledge gap in retinal metabolism after preterm birth.

Noncoding RNAs as a novel approach to target retinopathy of prematurity

Retinopathy of prematurity (ROP), a vascular disease characterized by abnormal vessel development in the retina, has become a primary cause of blindness in children around the world. ROP can be developed during two different phases: vessel loss and vessel proliferation. Once preterm infants with immature retinal vessel growth are exposed to high level of oxygen inside the incubator, vessel loss can occur. When infants are exposed to room air, they may experience the proliferation of vessels in the retina. Although multiple factors are reported to be involved in the pathogenesis of ROP, including vaso-endothelial growth factors (VEGFs) and hypoxia-inducible factors, the pathogenesis of ROP is not completely understood. Although laser therapy and pharmacologic agents, such as anti-VEGF agents, have been commonly used to treat ROP, the incidence of ROP is rapidly rising. Given that current therapies can be invasive and long-term effects are not fully known, the search for novel therapeutic targets with less destructive properties needs to be considered. Within the last decade, the field of noncoding RNA therapy has shown potential as next-generation therapy to treat diverse diseases. In this review, we introduce various noncoding RNAs regulating ROP and discuss their role as potential therapeutic targets in ROP.

Low- and Very Low-Dose Bevacizumab for Retinopathy of Prematurity: Reactivations, Additional Treatments, and 12-Month Outcomes

PURPOSE

Low-dose and very low-dose intravitreal bevacizumab (IVB) have been reported to be successful in short-term treatment of type 1 retinopathy of prematurity (ROP), down to an initial dose of 0.004 mg. We now report 12-month outcomes for these infants.

DESIGN

Masked, multicenter, dose de-escalation study.

PARTICIPANTS

One hundred twenty prematurely born infants with type 1 ROP.

METHODS

A cohort of 120 infants with type 1 ROP in at least 1 eye from 2 sequential dose de-escalation studies of low-dose IVB (0.25 mg, 0.125 mg, 0.063 mg, and 0.031 mg) or very low-dose IVB (0.016 mg, 0.008 mg, 0.004 mg, and 0.002 mg) to the study eye; the fellow eye (if also type 1) received 1 dose level higher of IVB. After primary success or failure at 4 weeks, clinical management was at investigator discretion, including all additional treatment.

MAIN OUTCOME MEASURES

Reactivation of severe ROP by 6 months corrected age, additional treatments, retinal and other ocular structural outcomes, and refractive error at 12 months corrected age.

RESULTS

Sixty-two of 113 study eyes (55%) and 55 of 98 fellow eyes (56%) received additional treatment. Of the study eyes, 31 (27%) received additional ROP treatment, and 31 (27%) received prophylactic laser therapy for persistent avascular retina. No trend toward a higher risk of additional ROP treatment related to initial IVB doses was found. However, time to reactivation among study eyes was shorter in eyes that received very low-dose IVB (mean, 76.4 days) than in those that received low-dose IVB (mean, 85.7 days). At 12 months, poor retinal outcomes and anterior segment abnormalities both were uncommon (3% and 5%, respectively), optic atrophy was noted in 10%, median refraction was mildly myopic (-0.31 diopter), and strabismus was present in 29% of infants.

CONCLUSIONS

Retinal structural outcomes were very good after low- and very low-dose IVB as initial treatment for type 1 ROP, although many eyes received additional treatment. The rate of reactivation of severe ROP was not associated with dose; however, a post hoc data-driven analysis suggested that reactivation was sooner with very low doses.

Retinopathy of Prematurity: A Global Perspective and Recent Developments

Retinopathy of prematurity (ROP) is a significant cause of potentially preventable blindness in preterm infants worldwide. It is a disease caused by abnormal retinal vascularization that, if not detected and treated in a timely manner, can lead to retinal detachment and severe long term vision impairment. Neonatologists and pediatricians have an important role in the prevention, detection, and management of ROP. Geographic differences in the epidemiology of ROP have been seen globally over the last several decades because of regional differences in neonatal care. Our understanding of the pathophysiology, risk factors, prevention, screening, diagnosis, and treatment of ROP have also evolved over the years. New technological advances are now allowing for the incorporation of telemedicine and artificial intelligence in the management of ROP. In this comprehensive update, we provide a comprehensive review of pathophysiology, classification, diagnosis, global screening, and treatment of ROP. Key historical milestones as well as touching upon the very recent updates to the ROP classification system and technological advances in the field of artificial intelligence and ROP will also be discussed.

New Aspects on the Treatment of Retinopathy of Prematurity: Currently Available Therapies and Emerging Novel Therapeutics

Retinopathy of prematurity (ROP) is a rare proliferative ocular disorder in preterm infants. Because of the advancements in neonatal care, the incidence of ROP has increased gradually. Now, ROP is one of the leading causes of blindness in children. Preterm infants with immature retinal development are exposed to supplemental oxygen inside an incubator until their cardiopulmonary system is adequately developed. Once they are returned to room air, the relatively low oxygen level stimulates various angiogenesis factors initiating retinal neovascularization. If patients with ROP are not offered adequate and timely treatment, they can experience vision loss that may ultimately lead to permanent blindness. Although laser therapy and anti-vascular endothelial growth factor agents are widely used to treat ROP, they have limitations. Thus, it is important to identify novel therapeutics with minimal adverse effects for the treatment of ROP. To date, various pharmacologic and non-pharmacologic therapies have been assessed as treatments for ROP. In this review, the major molecular factors involved in the pathogenesis of ROP, currently offered therapies, therapies under investigation, and emerging novel therapeutics of ROP are discussed.

Novel Role of Prereplication Complex Component Cell Division Cycle 6 in Retinal Neovascularization

BACKGROUND

The major aim of this study is to investigate whether CDC6 (cell division cycle 6), a replication origin recognition complex component, plays a role in retinal neovascularization, and if so, to explore the underlying mechanisms.

METHODS

In this study, we used a variety of approaches including cellular and moleculer biological methodologies as well as global and tissue-specific knockout mice in combination with an oxygen-induced retinopathy model to study the role of CDC6 in retinal neovascularization.

RESULTS

VEGFA (vascular endothelial growth factor A)-induced CDC6 expression in a time-dependent manner in human retinal microvascular endothelial cells. In addition, VEGFA-induced CDC6 expression was dependent on PLCβ3 (phospholipase Cβ3)-mediated NFATc1 (nuclear factor of activated T cells c1) activation. Furthermore, while siRNA-mediated depletion of PLCβ3, NFATc1, or CDC6 levels blunted VEGFA-induced human retinal microvascular endothelial cell angiogenic events such as proliferation, migration, sprouting, and tube formation, CDC6 overexpression rescued these effects in NFATc1-deficient mouse retinal microvascular endothelial cells. In accordance with these observations, global knockdown of PLCβ3 or endothelial cell-specific deletion of NFATc1 or siRNA-mediated depletion of CDC6 levels substantially inhibited oxygen-induced retinopathy-induced retinal sprouting and neovascularization. In addition, retroviral-mediated overexpression of CDC6 rescued oxygen-induced retinopathy-induced retinal neovascularization from inhibition in PLCβ3 knockout mice and in endothelial cell-specific NFATc1-deficient mice.

CONCLUSIONS

The above observations clearly reveal that PLCβ3-mediated NFATc1 activation-dependent CDC6 expression plays a crucial role in VEGFA/oxygen-induced retinopathy-induced retinal neovascularization.

Neurodevelopmental Outcomes Associated With Intravitreal Bevacizumab Injections for Retinopathy of Prematurity

BACKGROUND

Retinopathy of prematurity (ROP) is a common disorder among premature infants associated with significant morbidity. The current standard of care includes laser ablation therapy when needed. While intravitreal bevacizumab (IVB) injections have emerged as a new therapy for ROP, so have concerns about the systemic effects of the bevacizumab (Avastin), specifically on neurodevelopmental outcomes.

PURPOSE

To review the current literature on the impact of IVB on neurodevelopmental outcomes in neonates with ROP to inform nurses' knowledge and practice.

METHODS

A literature search was performed in the PubMed, CINAHL, and Embase databases. Eleven primary studies examining neurodevelopmental outcomes related to IVB were identified and reviewed.

RESULTS

Limitations of current studies, including small sample sizes, retrospective analysis subject to selection bias, and confounding factors such as sedation/anesthesia exposure, prevent robust conclusions from being drawn. However, there is not currently any clear evidence of negative neurodevelopmental impacts associated with IVB despite a sound theoretical basis for concern.

IMPLICATIONS FOR PRACTICE

Nurses should include all known and potential risks and benefits when counseling families and developing individualized plans of care for their neonatal patients with ROP.

IMPLICATIONS FOR RESEARCH

Well-designed, prospective studies examining neurodevelopmental outcomes at later time points are needed to conclusively support or disprove results of IVB therapy for ROP in the context of potential adverse effects.

Plasma Levels of Bevacizumab and Vascular Endothelial Growth Factor After Low-Dose Bevacizumab Treatment for Retinopathy of Prematurity in Infants

Importance

Intravitreal bevacizumab effectively treats severe retinopathy of prematurity (ROP), but it enters the bloodstream and may reduce serum vascular endothelial growth factor (VEGF), potentially causing detrimental effects on developing organs in the premature infant.

Objective

To evaluate the association of intravitreal bevacizumab with plasma bevacizumab and VEGF concentrations at 2 and 4 weeks after predefined, de-escalating doses of intravitreal bevacizumab were administered to infants with severe ROP.

Design, Setting, and Participants

This phase 1 dose de-escalation case series study was conducted at 10 US hospitals of ophthalmology institutions from May 21, 2015, to May 7, 2019. Blood samples were collected 2 and 4 weeks after intravitreal bevacizumab injection. Participants included 83 premature infants with type 1 ROP in 1 or both eyes and no previous ROP treatment. Data were analyzed from April 2017 to August 2021.

Interventions

Study eyes received a single bevacizumab injection of 0.250 mg, 0.125 mg, 0.063 mg, 0.031 mg, 0.016 mg, 0.008 mg, 0.004 mg, or 0.002 mg. When the fellow eye required treatment, one dose higher was administered. Total dose administered at baseline was defined as the sum of doses given to each eye within 3 days of initial study-eye injection.

Main Outcomes and Measures

Plasma bevacizumab concentration at 2 and 4 weeks after injection and the percentage change in plasma VEGF concentrations from pretreatment levels.

Results

A total of 83 infants (mean [SD] age, 25 [2] weeks; 48 boys [58%]) were included in this study. Higher doses of bevacizumab administered at baseline were associated with higher plasma bevacizumab concentrations at 2 weeks (ρ, 0.53; 95% CI, 0.31-0.70) and 4 weeks (ρ, 0.44; 95% CI, 0.18-0.64). Plasma VEGF concentrations decreased by 50% or more from pretreatment levels in 40 of 66 infants (61%) at 2 weeks and 31 of 61 infants (51%) at 4 weeks, but no association was observed between the total dose of bevacizumab administered at baseline and percentage change in plasma VEGF concentrations 2 weeks (ρ, -0.04; 95% CI, -0.28 to 0.20) or 4 weeks (ρ, -0.17; 95% CI, -0.41 to 0.08) after injection.

Conclusions and Relevance

Results of this phase 1 dose de-escalation case series study revealed that bevacizumab doses as low as 0.002 mg were associated with reduced plasma VEGF levels for most infants at 2 and 4 weeks after intravitreal administration; however, no association was observed between total bevacizumab dose administered and reductions in plasma VEGF levels from preinjection to 2 weeks or 4 weeks. Additional studies are needed to evaluate the long-term effects of low-dose bevacizumab on neurodevelopment and retinal structure.

Cognitive Outcomes Following Intravitreal Bevacizumab for Retinopathy of Prematurity: 4- to 6-Year Outcomes in a Prospective Cohort

PURPOSE

To determine the long-term cognitive outcomes in children who underwent intravitreal bevacizumab (IVB) for retinopathy of prematurity (ROP).

DESIGN

Prospective cohort study.

METHODS

This single-center study enrolled 186 children between 3 and 6 years of age and included 101 children in the final analysis: premature without ROP (group 1), ROP not needing treatment (group 2), IVB monotherapy (group 3), IVB plus laser therapy (group 4), and laser monotherapy (group 5). The Full-Scale Intelligence Quotient (FSIQ) was evaluated by the Wechsler Preschool and Primary Scale of Intelligence Test at baseline and then annually for 1-2 years and compared among groups.

RESULTS

The age at cognitive evaluation was 4.5-4.9 years at baseline and 6.1-7.0 years at the last follow-up. The FSIQ was comparable among the groups at both time points (P = .08 and .50, respectively). Severe cognitive impairment (FSIQ < 70) was more common in group 4 at baseline (4%, 22%, 13%, 33%, and 0% in groups 1-5, respectively; P = .03) but did not differ among the groups at the last follow-up (6%, 0%, 4%, 22%, and 0%; P = .22). After adjusting for sex, Apgar score, neonatal adverse events, and days on mechanical ventilation, IVB was not associated with FSIQ either at baseline or at the last follow-up.

CONCLUSIONS

At 4.5 to beyond 6 years of age, children who underwent IVB monotherapy had comparable cognitive outcomes compared to the other premature children without prior IVB. Children who underwent IVB plus laser showed higher severe cognitive impairment at 4.5 years of age.

Comparative Study between Curcumin and Nanocurcumin Loaded PLGA on Colon Carcinogenesis Induced Mice

Colorectal cancer is the third most common cancer. Because curcumin (CUR) has anti-inflammatory and anticancer properties, research has been undertaken to indicate that nanocurcumin compounds can be used to treat a variety of cancers. CUR in nanoform has been found to have a stronger effect than conventional CUR. The purpose of this study was to show that CUR-loaded poly lactic-co-glycolic acid nanoparticles (PLGA) (CUR-loaded PLGA) have anti-inflammatory and anticancer effects on colon carcinogenesis in male dimethyl hydrazine (DMH) mice as a comparative study between the nanoform of curcumin and normal curcumin, focusing on the anticancer effect of nanocurcumin. Mice were separated into six groups: No treatment was given to Group I (negative Group-I). Group II was treated with CUR. Group III was treated with CUR-loaded PLGA. Group IV was treated with DMH. Group V received DMH and curcumin. Group VI received DMH and CUR-loaded PLGA. At the conclusion of the trial, the animals were slain (6 weeks). Inflammatory indicators and vascular endothelial growth factor (VEGF) levels all changed significantly in this study, as the following inflammatory markers as TNF showed percent of change compared to the DMH group. Recovery percentage for Groups V and VI, respectively, were 9.18 and 55.31%. In addition, IL1 was 7.45 and 50.37% for Groups V and VI, respectively. The results of IL6 were 4.86 and 25.79% for Groups V and VI, respectively. The vascular endothelial growth factor (VEGF) recovery percent was 16.98 and 45.12% for Groups V and VI, respectively. Following the effect of DMH on colon mucosa shape, the researchers looked at the effect of CUR-loaded PLGA on colon histology. It was shown that CUR-loaded PLGA affects the cell cycle and PCNA expression. We conclude that nanocurcumin is an important anti-inflammatory and cancer-fighting agent.

Low-dose ranibizumab administration in retinopathy of prematurity

PURPOSE

To evaluate the efficiency of low-dose intravitreal ranibizumab therapy in the treatment of aggressive retinopathy of prematurity (A-ROP).

METHODS

A total of 124 eyes of 62 patients who underwent intravitreal ranibizumab after an A-ROP diagnosis between January 2015 and January 2021 were evaluated retrospectively. After receiving family-approved informed consent, low-dose intravitreal ranibizumab was administered, and regular follow-ups were performed.

RESULTS

Patients included in the study had a mean birth week of 26.6 (23-33 weeks), a mean birth weight of 905 (450-1970) grams, and an average injection postnatal time of 9.1 (4-19) weeks. The mean follow-up period was 63 (24-250) weeks. In all eyes, ROP regressed in the first week after injection, and no asymmetrical response was observed in the eyes of any baby. A total of 58 eyes recovered with a single dose of intravitreal injection therapy, and peripheral retinal vascularization was completed. A second injection was required in 38 eyes. Rescue treatment was applied in addition to intravitreal ranibizumab treatment in 22 eyes of 11 babies. None of the patients had any ocular or systemic side effects.

CONCLUSION

Low-dose intravitreal ranibizumab injection with close follow-up and appropriate timing is an effective treatment modality in A-ROP. Even among patients undergoing rescue laser treatment, the treatment can be completed with a wide visual field.

Short-term effects of intravitreal anti-vascular endothelial growth factor agents on body weight and multiple systems after treatment for retinopathy of prematurity

OBJECTIVES

This study's goal was to assess the short-term effect on body weight and multiple systems following intravitreal injections of ranibizumab and aflibercept for retinopathy of prematurity (ROP).

METHODS

We retrospectively assessed infants with ROP who received intravitreal anti-vascular endothelial growth factor agents (VEGF) treatment at our hospital. They were classified into 2 groups based on the drugs administered: the intravitreal ranibizumab (IVR) group and the intravitreal aflibercept (IVA) group. The body weight (BW) gains for the pre-treatment week, the 1st week after treatment, and the 2nd week after treatment were compared for each group. Additionally, other parameters such as blood pressure, heart rate, oxygen concentration, volume of milk and output of urine at four time points were also measured. We used repeated measurement analysis of variance analyzed these data.

RESULTS

In total, 95 preterm infants were recruited, including 51 cases in the IVR group and 44 cases in the IVA group. The BW gain for the 1st week after treatment was significantly lower than the pre-treatment week in each group (P < 0.05), while there was no decrease in weekly BW gain in the 2nd week after treatment compared with that pre-treatment week. Based on the comparison between groups, the BW gain in the IVR group was significantly higher than in the IVA group in the second post-treatment week. Repeated measurement analysis of variance showed that there were no significant differences in blood pressure, heart rate, oxygen concentration, volume of milk and output of urine in both groups over time.

CONCLUSIONS

IVR and IVA could have a short-term inhibitive effect on body weight gain in infants after treatment for ROP, whereas there is no significant impact on other systems.

Optimal Efficacy and Safety of Humanized Anti-Scg3 Antibody to Alleviate Oxygen-Induced Retinopathy

The retinopathy of prematurity (ROP), a neovascular retinal disorder presenting in premature infants, is the leading causes of blindness in children. Currently, there is no approved drug therapy for ROP in the U.S., highlighting the urgent unmet clinical need for a novel therapeutic to treat the disease. Secretogranin III (Scg3) was recently identified as a disease-selective angiogenic factor, and Scg3-neutralizing monoclonal antibodies were reported to alleviate pathological retinal neovascularization in mouse models. In this study, we characterized the efficacy and safety of a full-length humanized anti-Scg3 antibody (hAb) to ameliorate retinal pathology in oxygen-induced retinopathy (OIR) mice, a surrogate model of ROP, by implementing histological and functional analyses. Our results demonstrate that the anti-Scg3 hAb outperforms the vascular endothelial growth factor inhibitor aflibercept in terms of efficacy and safety to treat OIR mice. Our findings support the development of anti-Scg3 hAb for clinical application.

Effect of intravitreal bevacizumab for retinopathy of prematurity on weight gain

Purpose

To evaluate the short-term effect on body weight (BW) gain after intravitreal bevacizumab (IVB) for retinopathy of prematurity (ROP).

Methods

This was a retrospective 1:1 matched case-control study. Infants with ROP treated by IVB or photocoagulation (PC) at Shiga University of Medical Science Hospital between April 2010 and December 2019 were included in the study. To match BWs at treatment between the IVB and PC groups, 1:1 matching for BWs at treatment within 100 g was performed. The BW gains for the 7 days before treatment (pre-treatment week), the 7 days after treatment (first post-treatment week), and the period from 7 to 14 days after treatment (second post-treatment week) were compared between the IVB and PC groups.

Results

Following 1:1 matching, 13 infants in both groups were enrolled in the analysis. The weekly BW gain for the first post-treatment week was significantly lower in the IVB group compared with the PC group (86 g vs. 145 g; P = 0.046), whereas the weekly BW gains for the pre-treatment week (173 g vs. 159 g; P = 0.71) and the second post-treatment week (154 g vs. 152 g; P = 0.73) were comparable between the two groups. The short-term inhibitive effect of IVB on BW gain was particularly observed in infants weighing less than 1500 g at treatment (<1500 g: 47 g vs. ≥1500 g: 132 g; P = 0.03).

Conclusion

IVB could have a short-term inhibitive effect on BW gain in infants with ROP, and this effect is more likely to occur in infants with a lower BW at the time of treatment.

Recombinant thrombomodulin domain 1 rescues pathological angiogenesis by inhibition of HIF-1α-VEGF pathway

Pathological angiogenesis (PA) contributes to various ocular diseases, including age-related macular degeneration, diabetic retinopathy, and retinopathy of prematurity, which are major causes of blindness over the world. Current treatments focus on anti-vascular endothelial growth factor (VEGF) therapy, but persistent avascular retina, recurrent intravitreal neovascularization, and general adverse effects are reported. We have previously found that recombinant thrombomodulin domain 1 (rTMD1) can suppress vascular inflammation. However, the function of rTMD1 in VEGF-induced PA remains unknown. In this study, we found that rTMD1 inhibited VEGF-induced angiogenesis in vitro. In an oxygen induced retinopathy (OIR) animal model, rTMD1 treatment significantly decreased retinal neovascularization but spared normal physiological vessel growth. Furthermore, loss of TMD1 significantly promoted PA in OIR. Meanwhile, hypoxia-inducible factor-1α, the transcription factor that upregulates VEGF, was suppressed after rTMD1 treatment. The levels of interleukin-6, and intercellular adhesion molecule-1 were also significantly suppressed. In conclusion, our results indicate that rTMD1 not only has dual effects to suppress PA and inflammation in OIR, but also can be a potential HIF-1α inhibitor for clinical use. These data bring forth the possibility of rTMD1 as a novel therapeutic agent for PA.

Growth and neurodevelopmental status in patients with retinopathy of prematurity treated with intravitreal bevacizumab: a case-control study

Background

The current study aimed to evaluate growth and neurodevelopmental status in patients with retinopathy of prematurity (ROP) treated with intravitreal bevacizumab (IVB).

Methods

This historical cohort study was conducted on neonates with ROP who were treated with IVB and age and birth weight-matched controls who did not need IVB. Apgar score less than five, history of blood transfusion and history of infectious diseases were among exclusion criteria. Indirect ophthalmoscopic examinations were performed till complete retinal vascularization. Growth and neurodevelopmental status were evaluated by Age and Stages Questionnaire (ASQ) at the ages of 6, 12, and 18 months. Developmental milestones were assessed in five areas (gross motor, fine motor, personal-social status, problem-solving, and relationship) and overall issues.

Results

A total of 34 cases and 36 controls were included in the present study. Birth weight and corrected gestational age were not statistically different between the groups. In a follow-up period of 18 months, bevacizumab was effective as a primary treatment in the treatment of severe cases of ROP. There was no significant difference between the two groups regarding the five areas and overall issues in follow-up intervals (P > 0.05).

Conclusions

The obtained results did not show any growth and neurodevelopmental differences between treatment-naïve infants and those receiving IVB for the treatment of ROP.

Assessment and management of retinopathy of prematurity in the era of anti-vascular endothelial growth factor (VEGF)

The incidence of retinopathy of prematurity (ROP) continues to rise due to the improved survival of very low birth weight infants in developed countries. This epidemic is also fueled by increased survival of preterm babies with variable use of oxygen and a lack of ROP awareness and screening services in resource-limited regions. Improvements in technology and a basic understanding of the disease pathophysiology have changed the way we screen and manage ROP, educate providers and patients, and improve ROP awareness. Advancements in imaging techniques, expansion of telemedicine services, and the potential for artificial intelligence-assisted ROP screening programs have created opportunities to improve ROP care in areas with a shortage of ophthalmologists trained in ROP. To address the gap in provider knowledge regarding ROP, the Global Education Network for Retinopathy of Prematurity (GEN-ROP) created a web-based tele-education training module that can be used to educate all providers involved in ROP, including non-physician ROP screeners. Over the past 50 years, the treatment of severe ROP has evolved from limited treatment modalities to cryotherapy and laser photocoagulation. More recently, there has been growing evidence to support the use of anti-vascular endothelial growth factor (VEGF) agents for the treatment of severe ROP. However, VEGF is known to be important in organogenesis and microvascular maintenance, and given that intravitreal anti-VEGF treatment can result in systemic VEGF suppression over a period of at least 1-12 weeks, there are concerns regarding adverse effects and long-term ocular and systemic developmental consequences of anti-VEGF therapy. Future research in ophthalmology to address the growing burden of ROP should focus on cost-effective fundus imaging devices, implementation of artificial intelligence platforms, updated treatment algorithms with optimal use of anti-VEGF and careful investigation of its long-term effects, and surgical options in advanced ROP. Addressing these unmet needs will aid the global effort against the ROP epidemic and optimize our understanding and treatment of this blinding disease.

FACTORS ASSOCIATED WITH REACTIVATION AFTER INTRAVITREAL BEVACIZUMAB OR RANIBIZUMAB THERAPY IN INFANTS WITH RETINOPATHY OF PREMATURITY

PURPOSE

To investigate the efficacy and risk factors of intravitreal antivascular endothelial growth factor injection (anti-VEGF therapy) for retinopathy of prematurity (ROP).

METHODS

We retrospectively reviewed 80 consecutive eyes of 43 patients with Type 1 ROP or worse who received anti-VEGF therapy during January 2012-February 2018. Patients were divided into those who were injected with 0.25 mg of bevacizumab (IVB group, 37 eyes) and 0.25 mg of ranibizumab (IVR group, 43 eyes). Serum VEGF concentrations of 18 patients were measured before and after IVR.

RESULTS

Antivascular endothelial growth factor injection therapy reduced ROP activity in all eyes; however, 14 eyes (17.5%) exhibited reactivation. The reactivation rates of the IVB and IVR groups were 13.5% and 20.9%, respectively (P = 0.556). Multivariate logistic regression analysis showed that postmenstrual age ≤35 weeks at anti-VEGF therapy (P = 0.014) and aggressive posterior ROP (P = 0.044) was significantly associated with reactivation. Serum VEGF was significantly suppressed at Days 1 (P < 0.001) and 7 (P = 0.012) after IVR and returned to the preinjection level by Day 14 (P = 0.210).

CONCLUSION

Both IVR and IVB seemed effective in reducing ROP activity. Reactivation after anti-VEGF therapy may be associated with younger postmenstrual age at anti-VEGF therapy and aggressive posterior ROP.

Neurodevelopmental outcomes in preterm infants with retinopathy of prematurity

Over the past decade there has been a paradigm shift in the treatment of retinopathy of prematurity (ROP) with the introduction of antivascular endothelial growth factor (anti-VEGF) treatments. Anti-VEGF agents have the advantages of being easier to administer, requiring less anesthesia, having the potential for improved peripheral vision, and producing less refractive error than laser treatment. On the other hand, it is known that intravitreal administration of anti-VEGF agents lowers VEGF levels in the blood and raises the theoretical concern of intraocular anti-VEGF causing deleterious effects in other organ systems, including the brain. As a result, there has been increased attention recently on neurodevelopmental outcomes in infants treated with anti-VEGF agents. These studies should be put into context with what is known about systemic comorbidities, socioeconomic influences, and the effects of extreme prematurity itself on neurodevelopmental outcomes. We summarize what is known about neurodevelopmental outcomes in extremely preterm infants with ROP, discuss the implications for determining the neurodevelopmental status using neurodevelopmental testing as well as other indicators, and review the existing literature relating to neurodevelopmental outcomes in babies treated for ROP.

Complications of retinopathy of prematurity treatment

PURPOSE OF REVIEW

The purpose of this review is to summarize complications of treatment for retinopathy of prematurity (ROP) and to compare complications of laser and intravitreal antivascular endothelial growth factor (VEGF) injections.

RECENT FINDINGS

Poor structural outcomes and myopia are more common with laser for severe ROP than with anti-VEGF. Clinical trial data show unfavourable outcomes in 9.1-9.5% of laser treated, and 1.4-3.6% of anti-VEGF treated eyes. Additional randomized trial data show risk for very high myopia (≥-8.00D) to be 3.8 and 51.4% for zone I eyes treated with bevacizumab and laser, respectively. However, anti-VEGF may be complicated by late recurrence and is more likely to require retreatment than laser. Laser often necessitates general anaesthesia with its attendant risks, including worse short-term respiratory outcomes. Neurodevelopmental complications have been reported with anti-VEGF, but existing studies are subject to bias.

SUMMARY

Treatment complications are substantially different for the two modalities in common use today. In more severe cases, risk of poor structural outcome and myopia favour treatment with anti-VEGF. In less severe ROP, risk of recurrence and the need for additional treatments may favour laser. Additional data are needed to establish comparative risks of neurodevelopmental complications.

Aggressive Posterior Retinopathy of Prematurity (APROP): LASER as the Primary Modality of Treatment

Purpose

To study the success rate of LASER as a primary modality of treatment in aggressive posterior retinopathy of prematurity (APROP) cases.

Methods

This is a prospective case series of 56 eyes of 28 preterm babies (males = 21) with APROP who underwent laser therapy. Babies were divided into groups on the basis of gestational age (GA), birth weight (BW), and postmenstrual age (PMA) at which treatment was performed. GA (in weeks): <28 (n = 7), 28–30 (n = 11), >30 (n = 10). BW (in grams): <1000 (n = 8), 1000–1200 (n = 10), >1200 (n = 10). PMA (in weeks): < 32 (n = 6), 32–34 (n = 18), >34 (n = 4). Success was calculated as complete regression of disease without need for any other modality of treatment such as anti-vascular endothelial growth factor (anti-VEGF) or pars plana vitrectomy.

Results

The overall success rate was 94.64% (53/56). Two babies who needed additional modality of treatment were <28 weeks of GA (one eye) and 28–30 weeks (two eyes). One baby (one eye) was <1000 gm and the other (two eyes) was >1200 gm, while PMA at which additional treatment was needed was 30 weeks in one baby (one eye) and 33 weeks in the other (two eyes).

Conclusion

In this era of anti-VEGF treatment, even in cases of APROP, LASER should still be considered as a primary modality of treatment, as it is a one-time treatment without the concern of systemic side effects and recurrent/persistent avascular zones.

Association of Systemic or Intravitreal Antivascular Endothelial Growth Factor (Anti-VEGF) and Impaired Wound Healing in Pediatric Patients: Collagen to the Rescue

BACKGROUND

Bevacizumab is a humanized monoclonal antibody to vascular endothelial growth factor (VEGF) that has been used as a systemic chemotherapy treatment of various malignancies in adults since 2000. It has been used for pediatric patients over the last decade. In addition, bevacizumab is used for neonatal intravitreal administration for retinopathy of prematurity, a major complication of preterm birth, characterized by incomplete and abnormal vascularization of the retina that can lead to retinal detachment and blindness without treatment.

CASES

The objective of this multiple case series is to report impaired wound healing seen in 3 adolescents and 1 premature neonate receiving bevacizumab and to propose collagen-based dermal template as a choice for the management of such wounds. The 3 adolescents were undergoing treatment of malignancies and developed wound healing complication within weeks of receiving anti-VEGF. The premature neonate experienced an extravasation and had a slow wound healing trajectory after receiving intravitreal administration of bevacizumab for retinopathy of prematurity. All wounds achieved closure following topical treatment with a collagen dermal template.

CONCLUSION

Use of bevacizumab is increasing in the pediatric population. Clinicians should be aware of compromised wound healing and higher likelihood of wound dehiscence after bevacizumab administration. We recommend waiting for at least 4 to 6 weeks between anti-VEGF administration (either systemic or vitreous) and elective surgical procedures, consistent with adult literature recommendations. If patient has an existing wound, we assert that bevacizumab should not be administered until that wound is healed. If wound healing is stalled, we recommend dermal template as a safe and effective accelerator of wound healing.

Neurodevelopmental outcomes following bevacizumab treatment for retinopathy of prematurity: a systematic review and meta-analysis

OBJECTIVE

To systematically review the studies exploring the association between bevacizumab and neurodevelopmental outcomes.

METHODS

Embase, Medline, CINAHL, and Cochrane Library databases were searched for studies examining neurodevelopmental outcomes of preterm infants treated with bevacizumab compared to laser ablation or cryotherapy for severe retinopathy of prematurity (ROP).

RESULTS

Thirteen studies (clinical trial = 1; cohort studies = 12) were included. Random-effects model meta-analysis showed significant increased odds of cognitive impairment associated with bevacizumab treatment on both unadjusted (unadjusted odds ratio (OR) 1.61; 95% confidence interval (CI) 1.12, 2.30) and adjusted analyses (adjusted OR 1.90; 95% CI 1.22, 2.97). Infants treated with bevacizumab for severe ROP had significantly lower Bayley-III cognitive (mean difference (MD) -1.66; 95% CI -3.21, -0.12), and language composite scores (MD -5.50; 95% CI -8.24, -2.76) compared to infants treated with laser ablation or cryotherapy.

CONCLUSION

Bevacizumab treatment for severe ROP is associated with increased risk of cognitive impairment and lower cognitive and language scores in preterm infants.

Systemic conbercept pharmacokinetics and VEGF pharmacodynamics following intravitreal injections of conbercept in patients with retinopathy of prematurity

BACKGROUND

Data on serum vascular endothelial growth factor (VEGF) and drug levels in patients with retinopathy of prematurity (ROP) following intravitreal injections of conbercept (IVC) are lacking.

METHODS

Multicentre, prospective, non-randomised study of patients with aggressive posterior retinopathy of prematurity (APROP) or type 1 ROP who had not received other treatment. All infants received therapy in both eyes plus intravitreal IVC 0.25 mg/0.025 mL in one eye and had at least 6 months of follow-up. Blood samples were collected before and 1 week and 4 weeks after IVC. The main outcome measures were serum conbercept and VEGF concentrations.

RESULTS

Forty infants with APROP or type 1 ROP were enrolled. The mean serum VEGF at baseline and 1 week and 4 weeks after a total of 0.25 mg of IVC was 953.35±311.90 pg/mL, 303.46±181.89 pg/mL and 883.12±303.89 pg/mL, respectively. Serum VEGF 1 week after IVC was significantly lower (p<0.05) than baseline, and at 4 weeks after IVC, it was significantly higher (p<0.05) than at 1 week. There was no significant difference (p>0.05) between baseline and 4 weeks. Serum conbercept was below the limit of quantitation (BLOQ) at baseline and 4 weeks and was 19.81±7.60 ng/mL at 1 week.

CONCLUSION

Serum VEGF 1 week after IVC was significantly lower than baseline but returned to baseline at 4 weeks. Serum conbercept increased at 1 week and was BLOQ at 4 weeks.