Comparison of the 1-year Outcomes of Conbercept Therapy between Two Different Angiographic Subtypes of Polypoidal Choroidal Vasculopathy

The comparison of two different strategies of intravitreal conbercept for polypoidal choroidal vasculopathy in Chinese patients results from a 48-week randomized phase 4 study: STAR study

PURPOSE

To compare a treat-and-extend (TAE) strategy with a fixed dosing regimen of intravitreal conbercept (IVC) for the management of treatment-naïve polypoidal choroidal vasculopathy (PCV) patients.

METHODS

249 patients with treatment-naïve PCV were randomized 1:1 to fixed dosing regimen with injections every 12 weeks (3 + Q12W) group or treat-and-extend regimen(3 + TAE) group. Patients received 3 monthly intravitreal injections of 0.5 mg conbercept as loading dose in both groups. The 3 + Q12W patients were monitored monthly and received mandated injections every 12 weeks; the 3 + TAE patients were monitored and treated monthly until the resolution of exudative disease activity; the interval between visits was then individualized according to study protocol. Visual and anatomical outcomes were compared between the two groups.

RESULTS

At 48 weeks, there was no significant difference between the 3 + Q12W group and 3 + TAE group in mean BCVA improvement (p = 0.421), mean changes in central retinal thickness (CRT) (p = 0.818), maximum retinal thickness (MRT) (p = 0.448), pigment epithelial detachment (PED) height (p = 0.221), PED volume (p = 0.076), branching vascular network (BVN) area (p = 0.615), polypoidal lesion number (p = 0.701), polypoidal lesion area (p = 0.424), rates of patients who avoided vision loss of ≥15 ETDRS letters (p = 0.397) or complete polypoidal lesion regression rate (43.8% vs. 41.8%, p = 0.814). The 3 + Q12W group had more decreased retinal haemorrhage area (p = 0.014) and fewer mean numbers of injections comparing with 3 + TAE group (6.6 vs. 9.4, p < 0.001). Mean maximum extension interval between injections after loading injections was 9.6 ± 2.0 weeks for 3 + TAE group, with 27.8% of patients achieving an extension interval of 12 weeks and 61.1% patients 8 weeks or more.

CONCLUSIONS

Both 3 + Q12W and 3 + TAE regimens of IVC could result in improvement in visual and anatomical outcomes in PCV patients.

Relationship between Pachychoroid and Polypoidal Choroidal Vasculopathy

Previous clinical studies have suggested that pachychoroid can induce macular neovascularization (MNV) to develop pachychoroid neovasculopathy (PNV) and that PNV can progress to polypoidal choroidal vasculopathy (PCV). Recent studies based on the pachychoroid concept are now gradually revealing the true nature of, at least some part of, PCV. However, previous studies on PNV and/or PCV have used different frameworks for the classification of PNV, PCV, and neovascular age-related macular degeneration (nAMD). These have hampered the rapid overhaul of the understanding of PCV. Some investigators have assumed that all PCV is pachychoroid-driven whereas other investigators have classified PCV into “pachychoroid PCV” and “non-pachychoroid PCV”. Furthermore, since there is no consensus as to whether PNV includes PCV, some studies have included PCV with PNV, while other studies have excluded PCV from PNV. To address these gaps, we summarize previous studies on PCV and pachychoroid. Even before the proposal of the pachychoroid concept, previous studies had suggested that PCV could be divided into two subtypes, of which one was characterized by pachychoroid features. Previous studies had also provided keys to understand relationship between PCV and PNV. We here recommend a refined conceptual framework for future studies on PNV, PCV, and nAMD. Considering the current inconsistent understanding of PCV, we should be cautious about using the term PCV until we understand the true nature of PCV.

Short-Term Efficacy in Polypoidal Choroidal Vasculopathy Patients Treated With Intravitreal Aflibercept or Conbercept

Purpose

To compare the short-term efficacy in patients with polypoidal choroidal vasculopathy (PCV) treated using either aflibercept or conbercept.

Methods

This prospective study included 41 patients with treatment-naive PCV (42 eyes). All the patients were treated with either aflibercept or conbercept using an initial series of 3 monthly loading injections. Changes in the best-corrected logMAR visual acuity (BCVA) and anatomic outcomes were evaluated at 3 months.

Results

BCVA was improved with reduction in central choroidal thickness (CCT), central foveal thickness (CFT), and subretinal fluid (SRF) after 3 monthly loading injections in both aflibercept (IVA) and conbercept (IVC) groups. There was no significant difference in either visual or anatomic outcomes between the two groups after 3 months of treatment. However, compared with the IVC group, significantly higher BCVA improvement was observed in the patients in the IVA group with baseline BCVA better than 1. A visual outcome improved ≥3 lines in 13 patients in the IVA group (59%), and 9 patients in the IVC group (45%). A relatively high proportion of polyp regression was observed in the IVA group (63%) compared with the IVC group (55%) via OCTA.

Conclusions

Visual and anatomic outcomes were significantly improved in both IVA and IVC groups, but the results suggest a potentially superior short-term response in the IVA group.

Comparison of the Efficacy of Three Loading Doses of Intravitreal Injection of Conbercept with Injection Combined with PDT for the Treatment of PCV

Purpose

To compare the efficacy between initial 3-monthly intravitreal conbercept monotherapy and combination intravitreal conbercept with photodynamic therapy (PDT) for polypoidal choroidal vasculopathy (PCV).

Methods

This is a retrospective, comparative study which involved 65 PCV eyes of 65 patients. According to the therapeutic regimen, the PCV patients were divided into two groups: 32 eyes with naive PCV received a PDT after the first intravitreal injection of conbercept (IVC) followed by pro re nata (prn) retreatment (combination group), and 33 eyes with naïve PCV received 3-monthly IVC monotherapy followed by prn regimen (IVC monotherapy group). All patients completed at least 6 months of monthly follow-up.

Results

At month 6, best-corrected visual acuity (BCVA) improved significantly (P < 0.05) in both groups compared with that at baseline; the mean changes of BCVA between the IVC monotherapy group and combination group have no significant difference (−0.22 ± 0.22 vs. −0.17 ± 0.22 LogMAR, P = 0.38). The central retinal thickness (CRT) decreased significantly in the two groups (P < 0.05), with no difference between the two groups (P = 0.24). The complete regression rate of polyps was 58.6% (17 out of 29 eyes) in the IVC monotherapy group and 80.65% (25 out of 31 eyes) in the combination group, respectively (P = 0.09, χ-squared test). The combination group required significantly fewer injections than the IVC monotherapy group (3.09 ± 0.89 vs. 3.67 ± 0.74, P = 0.006).

Conclusion

Conbercept monotherapy significantly improved visual acuity and effectively regressed polyps during 6-month follow-up time in the treatment of PCV.

The Efficacy of Conbercept in Polypoidal Choroidal Vasculopathy: A Systematic Review

Methods

Thirty studies with 1308 eyes were identified and included in this study. The primary outcome measures were best-corrected visual acuity (BCVA), and secondary outcomes were optical coherence tomography characteristics and polyp regression rates. The pooled results were calculated by the random-effect or fixed-effect model according to the heterogeneity of the data.

Results

Despite a large standard deviation in means (SMD) improvement for BCVA and central retinal thickness (CRT) in the conbercept group, there was no statistically significant difference in the other outcomes compared to ranibizumab and aflibercept. However, there was a greater polyp regression rate in the conbercept group at 12 months.

Conclusions

This systematic review indicates that conbercept may achieve similar BCVA and CRT improvements as ranibizumab and aflibercept, with a superior rate of polyp regression at 12 months.

Association of ARMS2 genotype with response to anti-vascular endothelial growth factor treatment in polypoidal choroidal vasculopathy

BACKGROUND

To investigate whether genetic risk variants for age-related macular degeneration (AMD) are associated with response to intravitreal anti-vascular endothelial growth factor (VEGF) in polypoidal choroidal vasculopathy (PCV) patients.

METHODS

This prospective cohort study included 95 treatment-naïve patients that underwent anti-VEGF treatment for PCV for 12 months. Patients were genotyped for 10 single nucleotide polymorphisms in eight AMD-relevant genes. Genotypic association with visual and anatomic outcome measures at 12 months after initial treatment, including mean change in best-corrected visual acuity (BCVA) and total foveal thickness, visual gain of ≥ 15 letters, dry status on optical coherence tomography (OCT), pigment epithelial detachment (PED) regression on OCT, polyp regression on indocyanine green angiography, and injection numbers, were investigated using regression models with adjustment for non-genetic covariates under additive genetic model.

RESULTS

In 81 patients who completed 12-month anti-VEGF monotherapy without photodynamic therapy, significant pharmacogenetic association was found between ARMS2 rs10490924 and PED regression on OCT. Proportions of PED regression were 26.4% for TT, 45.7% for TG, and 63.6% for GG genotype, showing additive effect of G allele for higher chance of PED regression (OR, 2.96; 95% CI, 1.38-6.36; corrected P = 0.043). For entire 95 patients, no significant association was found between candidate polymorphisms and receiving photodynamic therapy within 12 months.

CONCLUSIONS

In PCV patients, ARMS2 rs10490924 showed association with anatomic therapeutic response to anti-VEGF, suggesting pharmacogenetic relationship.

Polypoidal Choroidal Vasculopathy

PURPOSE OF REVIEW

The goal of this paper is to review the recent literature of polypoidal choroidal vasculopathy (PCV) and provide an update on the epidemiology, pathophysiology, clinical findings, and management.

RECENT FINDINGS

Although indocyanine-green angiography (ICGA) is still the gold standard for diagnosis of PCV, the use of en face optical coherence tomography (OCT) and OCT angiography are useful tools in the diagnosis of PCV. Studies demonstrate superior treatment outcomes with combination photodynamic therapy (PDT) and anti-vascular endothelial growth factor (VEGF) therapy.

SUMMARY

PCV is a disease most commonly in Asians and African-Americans and presents with an orange-red nodule in the macula or the peripapillary region. While ICGA remains the most accurate method to diagnose PCV, newer non-invasive imaging modalities (eg. OCT-A and en face OCT) can be used to identify PCV lesions. The combination of PDT and anti-VEGF therapy is superior to either monotherapy. Future studies of OCT modalities and other anti-VEGF agents will be important in guiding PCV diagnosis and management, respectively.

Changes in Retinal Nerve Fiber Layer Thickness after Multiple Injections of Novel VEGF Decoy Receptor Conbercept for Various Retinal Diseases

Conbercept is a recombinant fusion protein with high affinity for all vascular endothelial growth factor isoforms and placental growth factor. The repeated intravitreal injection of conbercept may cause intraocular pressure (IOP) fluctuations and long-term suppression of neurotrophic cytokines, which could lead to retinal nerve fiber layer (RNFL) damage. This retrospective fellow-eye controlled study included 98 eyes of 49 patients. The changes in IOP and RNFL thickness as well as the correlation between RNFL changes and associated factors were evaluated. The IOP value between the baseline and the last follow-up visit in the injection group and the IOP value of the last follow-up visit between the injection and non-injection groups were not significantly different (p = 0.452 and 0.476, respectively). The global average thickness of the RNFL (μm) in the injection group decreased from 108.9 to 106.1; however, the change was not statistically significant (p = 0.118). No significant difference in the average RNFL thickness was observed at the last follow-up visit between the injection and non-injection groups (p = 0.821). The type of disease was the only factor associated with RNFL thickness changes. In conclusion, repeated intravitreal injections with 0.05 mL conbercept revealed an excellent safety profile for RNFL thickness, although short-term IOP changes were observed.