The effect of a single anti-Vascular Endothelial Growth Factor injection on neonatal growth and organ development: In-vivo study

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.

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.

Neurodevelopment of patients who received intravitreal bevacizumab or aflibercept for type 1 and aggressive retinopathy of prematurity

PURPOSE

We aimed to compare the neurodevelopment of patients who received intravitreal bevacizumab (IVB) and intravitreal aflibercept (IVA) for type 1 retinopathy of prematurity (ROP) and aggressive ROP (A-ROP) using the Ages and Stages Questionnaire (ASQ-3) test.

METHODS

Patients who underwent IVB (group 1), IVA (group 2), and patients who did not receive treatment (group 3) were included in the prospective-controlled study. The patients were grouped as low-intermediate-high risk according to the high-risk infant follow-up guide. With the ASQ-3 test, fine and gross motor movements, communication, problem solving, and personal-social developments of the patients were compared.

RESULTS

The gender distribution, birth weight (BW), and neonatal risk category of the groups were similar. Gestational age (GA) of group 1 was found to be lower compared to group 3. There was no difference between the groups in the development of gross and fine motor movements, communication and problem solving. The personal and social development of group 1 and group 2 was found to be retarded compared to the control group.

DISCUSSION

As a result, the detection of retardation in the personal and social areas in the treated patients, and the detection of retardation in other areas, although not significant, reveals the necessity of following the development of these patient groups and providing the necessary support in the areas where retardation is detected.

Pulmonary function in school-age children following intravitreal injection of bevacizumab for retinopathy of prematurity

The effect of anti-vascular endothelial growth factor on neonatal lung development was inconclusive. To evaluate pulmonary function in school-age children who have received intravitreal bevacizumab (IVB) for retinopathy of prematurity (ROP), this study included 118 school-aged children who were grouped into three groups: full-term control children (group 1), preterm children who had not received IVB treatment (group 2) and preterm children with ROP who had received IVB treatment (group 3). Pulmonary function was measured by spirometry and impulse oscillometry. Pulmonary function was significantly better in group 1 than in groups 2 and 3 (all p < 0.05 in forced vital capacity (FVC), forced expiratory volume in 1 s (FEV₁), forced expiratory flow between 25 and 75% of FVC (FEF_25-75), and respiratory resistance at 5 Hz and difference between respiratory resistance at 5 and 20 Hz (R5-R20). There were no statistically significant differences between group 2 and group 3 in all pulmonary function parameters, including FVC, FEV₁, ratio of FEV₁ to FVC, FEF_25-75, R5, R20, R5-R20, and respiratory reactance at 5 Hz. In conclusion, our study revealed that preterm infants receiving IVB for ROP had comparable pulmonary function at school age to their preterm peers who had not received IVB treatment.

Evaluation of Neurodevelopmental Outcomes in Premature Twins (Multigestations) with Retinopathy of Prematurity Receiving Anti-VEGF: A Comparison Study

Purpose

To assess possible neurodevelopmental delay (NDD) following intravitreal antivascular endothelial growth factor (VEGF) injection in neonates with retinopathy of prematurity (ROP).

Methods

In this retrospective cohort study, neurodevelopmental milestones in patients with a history of ROP and intravitreal bevacizumab (IVB) injection were compared with other gestations that received either no treatment or only a laser for treatment.

Results

One hundred and twenty-five neonates (of 59 multi-gestation pregnancies) were included in this study (with the range of age 1–7 years old). Sixty-five (51.18%) were male and sixty-two (48.81%) were female. The mean gestational age (GA) and birth weight of all neonates were 29.69 ± 1.57 weeks (ranges: 26–33 weeks) and 1312.50 ± 269.33 grs (ranges: 730–2100 grs). None of the neurodevelopmental outcomes were statistically different when two subgroups in group A (IVB vs. control) were compared. None of the differences between IVB and laser treated subgroups is statistically significant, except for “reaching for toys,” which was delayed in the laser treated subgroup (6.6 ± 2.5 and 6.9 ± 2.5 months in IVB and laser treated subgroups, respectively).

Conclusion

In neonates with ROP, there is no linear correlation between intravitreal anti-VEGF injection and neurodevelopmental delay.

New trends in intravitreal anti-VEGF therapy for ROP

Retinopathy of Prematurity (ROP) affects premature newborns, and it can cause childhood blindness and visual impairment if untreated. The understanding of the pathogenetic role of Vascular Endothelial Growth Factor (VEGF) has led to development of therapeutic strategies such as intravitreal anti-VEGF drugs. We reported drug efficacy and ROP recurrence rates, extrapolated from the reviewed studies. Association of Pegabtanib and laser photocoagulation confers efficacy in the regression of ROP stage 3 plus in zone I / II in 89.7% of treated eyes, reducing the recurrence rate to 14.6% compared to 50% of laser therapy alone. Irrespective of the dose, Ranibizumab demonstrated average efficacy greater than 75% on regression of active disease with the highest rates of the dose of 0.1 mg (92.5%). The recurrence, on the other hand, is the highest among this new anti-VEGF agents and is around an average of 41.5%, which records the highest values in the case of Aggressive Posterior Rop (APROP). Aflibercept at a dose of 1 mg demonstrated average efficacy of about 81.9% of treated infants, analyzing significantly fewer studies than Ranibizumab. The recurrence rate stands at an average of 28.9%, especially in the later forms of ROP. Using a dose of 0.25 mg of Conbercept, the disease regression rate is currently on average 83%, with an average recurrence rate of 15.24%, the peak of which was observed in cases of ROP in zone I. Further studies are needed to prove safety at long term, because,at the moment, only short-term data are available.

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.

Neurodevelopmental Outcomes after Bevacizumab Treatment for Retinopathy of Prematurity: A Meta-analysis

PURPOSE

To evaluate neurodevelopmental outcomes after intravitreal bevacizumab (IVB) therapy in retinopathy of prematurity (ROP) infants compared with those not exposed to IVB.

CLINICAL RELEVANCE

The primary concern regarding IVB treatment of ROP is the potential systemic side effects, especially the risk of causing severe neurodevelopmental impairment (sNDI). Results regarding neurodevelopmental outcomes after IVB therapy are conflicting.

METHODS

We conducted a meta-analysis and searched PubMed, Embase, and Web of Science for related publications from inception through March 12, 2020. The eligibility criteria were as follows: comparative studies of ROP patients that (1) included IVB as a treatment arm, (2) included a control group without bevacizumab treatment, and (3) reported on at least 1 neurodevelopmental outcome, such as sNDI, Bayley Scales of Infant and Toddler Development, Third Edition (Bayley III), composition scores, or cerebral palsy (CP). The primary outcome was sNDI, with the odds ratio (OR) calculated. Secondary outcomes were mean differences (MDs) for cognitive, language, and motor scores (Bayley III) and OR for CP. The quality of evidence was assessed using the Grades of Recommendation, Assessment, Development, and Evaluation approach.

RESULTS

Eight studies, 6 including laser-controlled ROP infants and 2 including ROP infants not requiring treatment, were included. The weighted OR for sNDI in the IVB group was 1.39 (95% confidence interval [CI], 0.98-1.97). The weighted MDs were -1.92 (95% CI, -4.73 to 0.88), -1.32 (95% CI, -4.65 to 1.99), and -3.66 (95% CI, -6.79 to -0.54) for cognitive, language, and motor scores in Bayley III, respectively. The OR for CP was 1.20 (95% CI, 0.56-2.55). No differences were observed between the preset subgroups comprising laser-controlled ROP infants and ROP infants not requiring treatment. The current quality of evidence was rated as low (sNDI and all Bayley III scores) to very low (CP).

CONCLUSIONS

Risk of sNDI was not increased in ROP patients after IVB treatment. Bayley III scores were similar in the IVB and control groups, except for a minor difference in motor performance. These findings suggest that the risk of additional sNDI after IVB treatment is low. Randomized trials are warranted to provide a higher quality of evidence.

Update on Anti-Vascular Endothelial Growth Factor Safety for Retinopathy of Prematurity

Retinopathy of prematurity (ROP) is a neovascular retinal disorder that occurs in infants born prematurely. Nowadays, ROP constitutes a leading cause of childhood blindness worldwide and for decades the standard of care has involved peripheral retinal ablation. However, this type of treatment requires the use of specialized equipment by well-trained physicians, has been associated with poor structural and visual outcomes in some preterm infants, and despite its adequate application, some cases of ROP may continue to progress. Therefore, the need for simpler and more efficient strategies made anti-vascular endothelial growth factor (anti-VEGF) medications an appealing option for treatment. Recently, the use of anti-VEGF agents for ROP has increased worldwide; nevertheless, this practice remains off-label, and there is a lack of information regarding its safety profile and the possibility of unfavorable long-term outcomes causes the utmost concern. This review updates the recent evidence regarding the systemic and ocular safety of anti-VEGF treatment for ROP.

Epithelial Membrane Protein 2 (EMP2) Promotes VEGF-Induced Pathological Neovascularization in Murine Oxygen-Induced Retinopathy

Purpose

Retinopathy of prematurity (ROP) is a leading cause of childhood blindness. ROP occurs as a consequence of postnatal hyperoxia exposure in premature infants, resulting in vasoproliferation in the retina. The tetraspan protein epithelial membrane protein-2 (EMP2) is highly expressed in the retinal pigment epithelium (RPE) in adults, and it controls vascular endothelial growth factor (VEGF) production in the ARPE-19 cell line. We, therefore, hypothesized that Emp2 knockout (Emp2 KO) protects against neovascularization in murine oxygen-induced retinopathy (OIR).

Methods

Eyes were obtained from wildtype (WT) and Emp2 KO mouse pups at P7, P12, P17, and P21 after normoxia or hyperoxia (P7-P12) exposure. Following hyperoxia exposure, RNA sequencing was performed using the retina/choroid layers obtained from WT and Emp2 KO at P17. Retinal sections from P7, P12, P17, and P21 were evaluated for Emp2, hypoxia-inducible factor 1α (Hif1α), and VEGF expression. Whole mount images were generated to assess vaso-obliteration at P12 and neovascularization at P17.

Results

Emp2 KO OIR mice demonstrated a decrease in pathologic neovascularization at P17 compared with WT OIR mice through evaluation of retinal vascular whole mount images. This protection was accompanied by a decrease in Hif1α at P12 and VEGFA expression at P17 in Emp2 KO animals compared with the WT animals in OIR conditions. Collectively, our results suggest that EMP2 enhances the effects of neovascularization through modulation of angiogenic signaling.

Conclusions

The protection of Emp2 KO mice against pathologic neovascularization through attenuation of HIF and VEGF upregulation in OIR suggests that hypoxia-induced upregulation of EMP2 expression in the neuroretina modulates HIF-mediated neuroretinal VEGF expression.

Anti-vascular endothelial growth factor intravitreal therapy for retinopathy of prematurity

Retinopathy of prematurity treatment modalities have expanded over the years, from cryotherapy to laser therapy and now, anti-vascular endothelial factor (VEGF) therapy by intravitreal injection. Use of anti-VEGF treatment varies regionally and depends on multiple factors including severity and progression of ROP, availability of alternative treatments, experience of the local ophthalmologists, medical status of the infant, and expectations for long-term follow-up. While the advantages and disadvantages of anti-VEGF intravitreal treatment on the eye are relatively well-described, few studies provide information about potential long-term systemic effects of this treatment, which is known to transiently reduce systemic VEGF concentrations.

Neurodevelopmental outcomes in infants treated with intravitreal bevacizumab versus laser

OBJECTIVE

To compare neurodevelopmental and visual outcomes in preterm infants treated with intravitreal bevacizumab (IVB) to laser ablation at 18-24 months corrected age.

STUDY DESIGN

A retrospective study was performed. The primary outcome was neurodevelopmental impairment (NDI). Secondary neurodevelopmental outcomes were significant NDI (sNDI), cerebral palsy, hearing loss, and composite scores of the Bayley Scales of Infant Development, Third edition. Visual outcomes included structural and refractive outcomes. Adjusted odds ratios (AOR) were calculated controlling for GA, sex, and ROP severity and confounding baseline characteristics using a cutoff of p < 0.20.

RESULTS

Thirty-four (60 eyes) infants receiving IVB and 30 (51 eyes) laser were included. No significant differences were identified in NDI (AOR 1.77, 95% CI 0.46, 6.73) or sNDI (AOR 2.31, 95% CI 0.75, 7.14). There were no other differences in outcomes.

CONCLUSIONS

Larger randomized trials are required to establish long-term efficacy and safety of IVB in preterm neonates.

Exosomes from Microglia Attenuate Photoreceptor Injury and Neovascularization in an Animal Model of Retinopathy of Prematurity

The role of microglia in the pathophysiology of ischemic retinal diseases has been studied extensively. Exosomes from microglial cells exert protective effects during several nervous system diseases, but their roles in hypoxia-induced retinopathy remain unclear. In our study, exosomes derived from microglial cells were injected into the vitreous body of mice with oxygen-induced retinopathy (OIR). Results showed that exosome-treated OIR mice exhibited smaller avascular areas and fewer neovascular tufts in addition to decreased vascular endothelial growth factor (VEGF) and transforming growth factor β (TGF-β) expression. Moreover, photoreceptor apoptosis was suppressed by exosome injection. Mechanistically, exosomes from microglial cells were incorporated into photoreceptors in vitro and inhibited the inositol-requiring enzyme 1α (IRE1α)-X-box binding protein 1 (XBP1) cascade, which contributes to hypoxia-induced photoreceptor apoptosis. Furthermore, the exosomes also downregulated the mRNA and protein levels of VEGF and TGF-β in hypoxia-exposed photoreceptors. A microRNA assay showed that microRNA-24-3p (miR-24-3p) levels were extremely high in exosomes from microglial cells, suggesting that this could be the key molecule that inhibits the hypoxia-induced expression of IRE1α in photoreceptors. These findings delineate a novel exosome-mediated mechanism of microglial cell-photoreceptor crosstalk that facilitates normal angiogenesis and visual function in OIR mice; thus, our results also suggest a potential therapeutic approach for retinopathy of prematurity.