Intravitreal conbercept improves outcome in patients undergoing vitrectomy for proliferative diabetic retinopathy: A systematic review and meta-analysis

Effect of Adjunctive Intravitreal Conbercept Injection at the End of 25G Vitrectomy on Severe Proliferative Diabetic Retinopathy: 6-Month Outcomes of a Randomised Controlled Trial

INTRODUCTION

This study aimed to evaluate the effect of pre-operative versus pre-operative plus post-operative intravitreal conbercept (IVC) injection on severe proliferative diabetic retinopathy (PDR).

METHODS

This was a prospective, comparative and randomised study. A total of 84 patients who underwent vitrectomy for severe PDR were included in this study. Patients were randomly divided into control (41 eyes) and experiment (43 eyes) groups. Patients in the experiment group received adjunctive pre-operative and post-operative IVC injection, whereas patients in the control group only received pre-operative IVC injection. The incidence of post-operative vitreous haemorrhage (POVH), best-corrected visual acuity (BCVA) and central retinal thickness (CRT) were determined.

RESULTS

The incidence of early POVH was significantly different between the two groups, but no significant difference was observed between groups at 3 and 6 months. In the experiment group, the BCVA was significantly improved 1 month after surgery when compared with the control group (p 0.019). There was no marked difference in the mean post-operative BCVA at 3 and 6 months between groups (p 0.063 and 0.082). CRT was significantly lower in the experiment group than in the control group at 1 and 3 months after surgery (p 0.037 and 0.041), but there was no significant difference at 6 months (p 0.894).

CONCLUSION

Additional IVC injected at the end of surgery improves the POVH and BCVA at the early stage after surgery in severe PDR, but this benefit is absent at 6 months. Further studies are needed to investigate the effect of IVC at the end of vitrectomy.

TRIAL REGISTRATION

chictr.org.cn identifier: ChiCTR2200060735. Retrospectively registered, register date: 9 June 2022.

Differences in aqueous humor protein profiles in patients with proliferative diabetic retinopathy before and after conbercept treatment

To investigate the changes in aqueous humor (AH) protein profiles before and after intravitreal conbercept (IVC) treatment in proliferative diabetic retinopathy (PDR) patients. Ten PDR patients provided 20 samples of AH before (pre group) and after (post group) IVC treatment. Liquid chromatography-tandem mass spectrometry was performed to identify proteins. Bioinformatics analysis was used to explore the functional relevance of differentially expressed proteins (DEPs) and hub proteins. Parallel reaction monitoring (PRM) method was used to verify the hub proteins in another 8 samples of AH before and after IVC treatment in 4 PDR patients. A total of 30 DEPs were identified, consisting of 14 downregulated proteins and 16 upregulated proteins. Bioinformatics analysis indicated that DEPs mostly involved in neutrophil degranulation, antioxidant activity, secretory granule lumen, cytoplasmic vesicle lumen, vesicle lumen, and fluid shear stress. HP, VEGFA, CTSD, and LYZ were identified as hub proteins, among which HP and CTSD were verified by PRM. In addition to decreasing the intravitreal vascular endothelial growth factor level, IVC may alter the AH protein profile in PDR patients, especially HP and CTSD, with the DEPs involved in neutrophil degranulation, antioxidant activity, secretory granule lumen, cytoplasmic vesicle lumen, vesicle lumen, and fluid shear stress. SIGNIFICANCE: Patients with proliferative diabetic retinopathy (PDR) regularly receive intravitreal conbercept treatment these days. The effect of this treatment has been determined by previous studies. However, the mechanism of IVC in PDR is not eventually determined. No studies have compared the aqueous humor (AH) protein profile before and after IVC treatment in the same patient. This is a topic deserving of further exploration. A proteomic method based on liquid chromatography-tandem mass spectrometry (LC-MS/MS) was utilized in this study to analyze and assess the AH samples to explore the mechanism underlying the effects of IVC treatment on PDR.

Network meta-analysis of intravitreal conbercept as an adjuvant to vitrectomy for proliferative diabetic retinopathy

Purpose

Intravitreal Conbercept (IVC) has been shown to be effective in treating proliferative diabetic retinopathy (PDR) as an adjuvant in pars plana vitrectomy (PPV); however, the best timing of IVC injection remains unknown. This network meta-analysis (NMA) sought to ascertain the comparative efficacy of different timings of IVC injection as an adjuvant to PPV on PDR.

Methods

A comprehensive literature search was conducted in PubMed, EMBASE, and the Cochrane Library to identify relevant studies published before August 11, 2022. According to the mean time of IVC injection before PPV, the strategy was defined as very long interval if it was > 7 days but ≤ 9 days, long interval if it was > 5 days but ≤ 7 days, mid interval if it was > 3 days but ≤ 5 days, and short interval if it was ≤ 3 days, respectively. The strategy was defined as perioperative IVC if IVC was injected both before and at the end of PPV, and the strategy was intraoperative IVC if injected immediately at the end of PPV. The mean difference (MD) and odds ratio (OR) with corresponding 95% confidence interval (CI) for continuous and binary variables, respectively, were computed through network meta-analysis using Stata 14.0 MP.

Results

Eighteen studies involving 1149 patients were included. There was no statistical difference between intraoperative IVC and control in treating PDR. Except for a very long interval, preoperative IVC significantly shortened operation time, and reduced intraoperative bleeding and iatrogenic retinal breaks. Long and short intervals reduced endodiathermy application, and mid and short intervals reduced postoperative vitreous hemorrhage. Moreover, long and mid intervals improved BCVA and central macular thickness. However, very long interval was associated with an increased risk of postoperative vitreous hemorrhage (RR: 3.27, 95%CI: 1.84 to 5.83). Moreover, mid interval was better than intraoperative IVC in shortening operation time (MD: -19.74, 95%CI: -33.31 to -6.17).

Conclusions

There are no discernible effects of intraoperative IVC on PDR, but preoperative IVC, except for very long interval, is an effective adjuvant to PPV for treating PDR.

Downregulation of angiogenic factors in aqueous humor associated with less intraoperative bleeding in PDR patients with NVG receiving conbercept: a randomized controlled trial

BACKGROUND

To analyze the level changes of 28 cytokines in aqueous humor of patients with proliferative diabetic retinopathy (PDR) coexisting neovascular glaucoma (NVG) after intravitreal injection of conbercept (IVC), and to investigate whether these cytokines are associated with intraoperative bleeding (IOB).

METHODS

Totally 34 eyes with NVG secondary to PDR were enrolled. Patients were randomized into two groups, and all of them underwent 25-gauge pars plana vitrectomy (PPV) combined with trabeculectomy. Group I, 18 eyes received IVC 3 days before PPV, and 100 µL aqueous humor was collected at the time of IVC pretreatment and 3 days later at the beginning of PPV respectively. Group II, 16 eyes received IVC after PPV, and 100 µL aqueous humor was collected only at the beginning of PPV. Aqueous humor from 19 eyes with age-matched cataract patients served as controls. Luminex bead-based multiplex array was used to measure the levels of 28 cytokines in aqueous humor. The baseline cytokine levels were compared among the three groups. All NVG patients were divided into IOB and non-bleeding (INB) groups. The cytokine levels of aqueous humor at the beginning of PPV were compared between group I and II, also between IOB and INB groups. IOB in NVG patients was graded according to vitreous bleeding amount. The correlation between cytokine levels and the grades of IOB were analyzed.

RESULTS

Compared with controls, the baseline levels of 18 cytokines associated with inflammation and angiogenesis showed significantly increased in group I and group II (all, P < 0.0167). The IOB rate as well as the levels of IL-4, IL-22, Ang-2, PLGF and VEGF-A in group I were significantly lower than in group II (all, P < 0.05). The levels of IL-4, IL-22, Ang-2, PLGF and VEGF-A were significantly lower in INB group than in IOB group (all, P < 0.05). The levels of IL-4, Ang-2, PLGF and VEGF-A were positively correlated with the grades of IOB in NVG patients (all, r_s > 0.4, P < 0.05).

CONCLUSIONS

IVC 3 days before PPV combined with trabeculectomy reduces IOB in NVG patients, in which the downregulation of IL-4, Ang-2, PLGF and VEGF-A after IVC may be an underlying mechanism.

TRIAL REGISTRATION

ChiCTR2100048118 , retrospectively registered on 2 July 2021.

Intravitreal conbercept as an adjuvant in vitrectomy for proliferative diabetic retinopathy: a meta-analysis of randomised controlled trials

PURPOSE

To evaluate the efficacy of intravitreal conbercept (IVC) in pars plana vitrectomy (PPV) for patients with proliferative diabetic retinopathy (PDR).

METHODS

A meta-analysis of randomized control trials (RCTs) using online databases was performed. The intraoperative outcome measures were the incidence of intraoperative bleeding and endodiathermy application, and the mean surgical time. The postoperative outcome measures were mean change in best-corrected visual acuity (BCVA) from baseline, postoperative vitreous clear-up time and incidence of recurrent vitreous hemorrhage (VH).

RESULTS

Eight RCTs were selected for meta-analysis. They included 409 eyes (215 eyes in IVC group and 194 eyes in no conbercept group). Preoperative IVC application was associated with less intraoperative bleeding and endodiathermy applications (RR = 0.34, 95% CI, 0.23-0.50, P < 0.00001, and RR = 0.26, 95% CI, 0.12-0.56, P = 0.0005) compared to no conbercept. It also shortened surgical time (WMD = -15.87, 95% CI, -22.04 to -9.69, P < 0.00001). In addition, preoperative or intraoperative IVC achieved better BCVA outcome (WMD = -0.37, 95% CI, -0.62 to -0.13, P = 0.003), shorter vitreous clear-up time postoperatively (WMD = -5.44, 95% CI, -6.31 to -4.57, P < 0.00001) and a lower rate of VH recurrence (RR = 0.45, 95% CI, 0.22-0.91, P = 0.03).

CONCLUSION

IVC is an effective adjuvant in PPV for PDR, with better intraoperative and postoperative outcomes.

Comparative efficacies of different immunotherapy regimens in recurrent implantation failure: A systematic review and network meta-analysis

For patients with recurrent implantation failure (RIF), immune system imbalances have become the focus of research. The effects of different classes of immunotherapies on improving pregnancy outcomes have not been fully established. This network meta-analysis was performed to assess the impact of popular immunotherapies in women with RIF. We systematically searched the Cochrane Central Register of Controlled Trials, PubMed, Embase, and Web of Science databases as well as clinical trial registration websites. Randomized controlled trials comparing immunotherapeutic outcomes were included. We performed the random-effects network meta-analysis to compare efficacy measures. A total of 21 trials involving 2277 participants and 8 immunotherapies were eligible for this study. Patients that had been administered with PBMCs, G-CSF, PRP, and sirolimus exhibited higher CPR than those administered with the placebo (2.63, 1.71-4.06; 2.03, 1.35-3.05; 1.98, 1.02-3.84; 2.55, 1.36-4.79; and 3.95, 1.33-11.72, respectively). For IR, only PBMCs and G-CSF were significantly more effective than the placebo (2.92, 1.39-6.12; 2.66, 1.16-6.06, respectively). In terms of LBR, PBMCs (2.96, 1.67-5.27) and sirolimus (3.55, 1.18-10.64) were effective. However, r-hLIF (0.25, 0.10-0.62) had a reduced risk of LBR. No therapeutic regimen was found to have significantly decreased MR, but PBMCs exhibited the lowest rank among all interventions (0.28, 0.06-1.44). To improve clinical pregnancy while reducing miscarriage outcomes, PBMCs might be a beneficent therapeutic option for RIF in the future.