Serum levels of intravitreal bevacizumab after vitrectomy, lensectomy and non-surgical controls

Intra-Anterior Chamber Injection of Ranibizumab in Advanced Pediatric Vitreoretinal Diseases

Importance

Anti-vascular endothelial growth factor (VEGF) treatment through intravitreal or subretinal administrations has been proven effective for VEGF-driven pediatric vitreoretinal diseases but are not feasible for advanced cases, such as shallow traction retinal detachments or peripheral circumferential retinal detachments which adhere to the lens. Intra-anterior chamber injection (IAcI) of anti-VEGF may be a viable alternative in such cases but needs evaluation.

Objective

To investigate the effects and safety of IAcI of anti-VEGF to treat VEGF-driven pediatric vitreoretinal diseases.

Design, Setting, and Participants

This was a retrospective observational case series study conducted at Xinhua Hospital, affiliated with Shanghai Jiao Tong University School of Medicine in China. The study included 14 eyes of 13 children diagnosed with vitreoretinal disease exhibiting elevated vascular activity between January and August 2023.

Intervention

IAcI with ranibizumab.

Main Outcomes and Measures

Retinal vascular abnormalities, vitreous hemorrhage resolution, and complications 1 month and 3 months after injection.

Results

Of 13 patients included in this study, 12 were male. The mean age was 4.6 years (range, 1 month to 9 years). Six patients were diagnosed with familial exudative vitreoretinopathy, 4 with morning glory syndrome, 1 with retinopathy of prematurity, and 2 with chronic retinal detachments of unknown causes. At 1-month postoperative follow-up, vascular activity had decreased in 14 of 14 eyes. At 3-month follow-up, vascular activity had resolved in 7 of 14 eyes, persisted in 6 of 14 eyes, and reactivated in 1 of 14 eyes. On final observation, no complications were reported.

Conclusions and Relevance

These findings support the possibility of treatment using IAcI with ranibizumab to decrease retinal vascular abnormalities in familial exudative vitreoretinopathy or retinopathy of prematurity or related conditions, but further studies are needed to understand more precise benefits and risks. This approach might be considered in cases where intravitreal or subretinal injection are not feasible, recognizing the limitations of these findings and that longer-term outcomes still need to be monitored.

Intravitreal anti-VEGF drug delivery systems for age-related macular degeneration

Age-related macular degeneration is the most common cause of vision loss in elderly people in developed countries. Nowadays, in clinical practice, three anti-VEGF drugs are commonly used (bevacizumab, aflibercept and ranibizumab), requiring repeated intravitreal injections. In order to minimise the number of injections, research on intravitreal drug delivery systems (DDSs) is needed. In this review, the DDSs developed up to date regarding intravitreal anti-VEGF drugs have been summarised, which include systems as hydrogels, liposomes, microparticles, nanoparticles or implants. Most of the studies have focused on the extended in vitro release behaviour of the developed DDSs, but data as antibody bioactivity, biocompatibility or in vivo stability is sometimes scarce. Moreover, as DDS development relies on in vivo pharmacokinetic analyses to evaluate the extended drug release, all the information regarding anti-VEGF intravitreal pharmacokinetics in different animal species have been compiled.

Preoperative Intravitreal Conbercept Facilitates Vitrectomy in Proliferative Diabetic Retinopathy: Is Attention Required for the Fellow Eye?

Purpose

To evaluate the effect of preoperative intravitreal conbercept (IVC) injection on patients with proliferative diabetic retinopathy (PDR).

Methods

Medical records of patients who underwent vitrectomy due to complications of PDR were retrospectively reviewed. Patients were grouped as the IVC group and non-IVC group according to preoperative IVC. Preoperative, intraoperative, and postoperative data of both eyes were collected. The main outcome measures were best-corrected visual acuity (BCVA), intraocular pressure (IOP), central retinal thickness (CRT), and incidence of tractional retinal detachment (TRD).

Results

A total of 37 cases were included, 16 in the IVC group and 21 in the non-IVC group. Preoperative IVC significantly reduced surgical duration (IVC vs. non-IVC, 88.9 ± 11.9 min vs. 97.8 ± 12.8 min, p  <  0.05). In the vitrectomized eye, no significant difference existed between the IVC group and non-IVC group regarding postoperative BCVA (logMAR, 1.20 ± 0.53 vs. 1.27 ± 0.54, p = 0.68), IOP (16.5 ± 2.9 mmHg vs. 15.6 ± 3.7 mmHg, p = 0.44), and CRT (330.1 ± 35.2 μm vs. 319.2 ± 32.5 μm, p=0.34). In the fellow eye, 6 cases in the IVC group were diagnosed with TRD during postoperative follow-up, while only 2 cases were diagnosed in the non-IVC group (p  <  0.05).

Conclusion

Preoperative intravitreal injection of conbercept has effectively facilitated vitrectomy in PDR patients, but it potentially promotes tractional retinal detachment in the fellow eye following preoperative injection.

Pharmacokinetics of Intravitreal Anti-VEGF Drugs in Age-Related Macular Degeneration

Intravitreal administration of anti-vascular endothelial growth factor (VEGF) antibodies has become the standard treatment for Age-Related Macular Degeneration; however, the knowledge of their pharmacokinetics is limited. A comprehensive review of the preclinical and clinical pharmacokinetic data that were obtained in different studies with intravitreal bevacizumab, ranibizumab, and aflibercept has been conducted. Moreover, the factors that can influence the vitreous pharmacokinetics of these drugs, as well as the methods that were used in the studies for analytical determination, have been exposed. These anti-VEGF drugs present different charge and molecular weights, which play an important role in vitreous distribution and elimination. The pharmacokinetic parameters that were collected differ depending on the species that were involved in the studies and on physiological and pathological conditions, such as vitrectomy and lensectomy. Knowledge of the intravitreal pharmacokinetics of the anti-VEGF drugs that were used in clinical practice is of vital importance.

A comparison of responses to intravitreal bevacizumab, ranibizumab, or aflibercept injections for neovascular age-related macular degeneration

PURPOSE

To compare the responses of intravitreal injections of bevacizumab, ranibizumab, or aflibercept for the treatment of neovascular age-related macular degeneration (nAMD).

METHODS

This retrospective study examined 232 eyes of 232 patients who received intravitreal anti-vascular endothelial growth factor (VEGF) injections due to treatment-naïve nAMD. All patients, who were followed-up for at least 1 year, were treated with intravitreal injections monthly until 3 months, and then as needed. We evaluated the effects of intravitreal injections for treatment of nAMD using the central macular thickness (CMT), subretinal fluid (SRF), pigment epithelial detachment (PED) size, and best-corrected visual acuity (BCVA).

RESULTS

CMT, SRF, PED size, and BCVA (LogMAR) were significantly decreased after treatment with all three anti-VEGF agents. Overall, the bevacizumab, ranibizumab, and aflibercept treatments showed no significant differences in their responses. However, the aflibercept injections decreased PED size more quickly than bevacizumab injections (P = 0.034).

CONCLUSIONS

Bevacizumab, ranibizumab, and aflibercept injections are effective treatments for nAMD and have similar responses, although the number of injections of aflibercept was fewer than other anti-VEGF agents. In addition, aflibercept injections may be a better choice than other anti-VEGF agents for cases of severe increases in PED height.

Epimacular Brachytherapy for Previously Treated Neovascular Age-Related Macular Degeneration (MERLOT): A Phase 3 Randomized Controlled Trial

PURPOSE

To assess the safety and efficacy of epimacular brachytherapy (EMB) for patients with chronic, active, neovascular age-related macular degeneration (AMD).

DESIGN

Phase 3 randomized controlled trial.

PARTICIPANTS

Patients (n = 363) with neovascular AMD already receiving intravitreal ranibizumab injections.

INTERVENTION

Either pars plana vitrectomy with 24-gray EMB and ongoing pro re nata (PRN) ranibizumab (n = 224) or ongoing PRN ranibizumab monotherapy (n = 119).

MAIN OUTCOME MEASURES

The coprimary outcomes, at 12 months, were the number of PRN ranibizumab injections and Early Treatment of Diabetic Retinopathy Study (ETDRS) best-corrected visual acuity (VA). Secondary outcomes included the proportion of participants losing fewer than 15 ETDRS letters, angiographic total lesion size, choroidal neovascularization (CNV) size, and optical coherence tomography (OCT) foveal thickness. A predefined subgroup analysis tested the influence of baseline ocular characteristics on the response to EMB.

RESULTS

The mean number of PRN ranibizumab injections was 4.8 in the EMB arm and 4.1 in the ranibizumab monotherapy arm (P = 0.068). The mean VA change was -4.8 letters in the EMB arm and -0.9 letters in the ranibizumab arm (95% confidence interval of difference between groups, -6.6 to -1.8 letters). The proportion of participants losing fewer than 15 letters was 84% in the EMB arm and 92% in the ranibizumab arm (P = 0.007). In the EMB arm, the mean total lesion size increased by 1.2 mm(2) versus 0.4 mm(2) in the ranibizumab arm (P = 0.27). The CNV size decreased by 0.5 mm(2) in the EMB arm and by 1.3 mm(2) in the ranibizumab arm (P = 0.27). The OCT foveal thickness decreased by 1.0 μm in the EMB arm and by 15.7 μm in the ranibizumab arm (P = 0.43). Most subgroups favored ranibizumab monotherapy, some significantly so. One participant showed retinal vascular abnormality attributed to radiation, but otherwise safety was acceptable.

CONCLUSIONS

These results do not support the use of EMB for chronic, active, neovascular AMD. Safety is acceptable out to 12 months, but radiation retinopathy can occur later, so further follow-up is planned.

The role of epiretinal membrane on treatment of neovascular age-related macular degeneration with intravitreal bevacizumab

Purpose. To determine the effect of epiretinal membranes (ERM) on the treatment response and the number of intravitreal bevacizumab injections (IVB) in patients with neovascular age-related macular degeneration (nAMD). Methods. A retrospective chart review was performed on 63 eyes of 63 patients. The patients were divided into AMD group (n = 35) and AMD/ERM group (n = 28). Best corrected visual acuity (BCVA) and central retinal thickness (CRT), as well as the number of injections, were evaluated. Results. There was a significant improvement in BCVA at 3 months for the AMD and AMD/ERM groups (P = 0.02, P = 0.03, resp.). At 6, 12, and 18 months, BCVA did not change significantly in either of the groups compared to baseline (P > 0.05 for all). At 3, 6, 12, and 24 months, the AMD group had an improvement in BCVA (logMAR) of 0.09, 0.06, 0.06, and 0.03 versus 0.08, 0.07, 0.05, and 0.03 for the AMD/ERM group (P = 0.29, P = 0.88, P = 0.74, P = 0.85, resp.). A significant decrease in CRT occurred in both groups for all time points (P < 0.001 for all). The change in CRT was not statistically different between the two groups at all time points (P > 0.05 for all). The mean number of injections over 24 months was 8.8 in the AMD group and 9.2 in the AMD/ERM group (P = 0.76). Conclusion. During 24 months, visual and anatomical outcomes of IVB in nAMD patients were comparable with those in nAMD patients with ERM with similar injection numbers.