Novel Dual-Targeting Antibody Fragment IDB0062 Overcomes Anti-Vascular Endothelial Growth Factor Drug Limitations in Age-Related Macular Degeneration

Determination of Vascular Endothelial Growth Factor-B Concentrations in Aqueous Humor and Plasma of Neovascular Age-Related Macular Degeneration and Polypoidal Choroidal Vasculopathy Patients Before and After Anti-VEGF Therapy

INTRODUCTION

Anti-vascular endothelial growth factor (anti-VEGF) injection was widely used in patients with neovascular age-related macular degeneration (nAMD) and polypoidal choroidal vasculopathy (PCV); however, the systemic and local levels of vascular endothelial growth factor (VEGF)-B were seldom detected before. This study was conducted to detect and compare the aqueous humor and plasma VEGF-B levels in nAMD and PCV before and after anti-VEGF therapy.

METHODS

Concentrations of VEGF-B in aqueous humor and plasma of individuals with nAMD (n = 10), PCV (n = 22), and age-related cataract controls (n = 12) were measured by enzyme-linked immunosorbent assay. Ranibizumab was injected intravitreally in patients monthly for three consecutive months. Before each injection in patients and at the baseline of controls, blood and aqueous humor samples were collected. Best-corrected visual acuity (BCVA) and central retinal thickness (CRT) were collected before each injection in patient groups. The differences of BCVA, CRT, and VEGF-B levels in aqueous humor and plasma between groups before and after anti-VEGF therapy were compared.

RESULTS

VEGF-B was overexpressed in aqueous humor and plasma of nAMD and PCV groups compared with control group (P < 0.05), but no statistically significant difference existed across nAMD and PCV groups (P > 0.05). Moreover, there were no obvious difference in levels of VEGF-B in aqueous humor and plasma within the treatment groups after anti-VEGF treatment (P > 0.05). The mean CRT in the nAMD group was thinner than that in the PCV group at baseline (P < 0.01). After injections, the CRT obviously declined in both groups (P < 0.05). There was no correlation between CRT reduction and high VEGF-B expression in aqueous humor and plasma of treatment groups.

CONCLUSION

Overexpression of VEGF-B locally and systemically in patients with nAMD and PCV indicated that elevated VEGF-B concentrations were relevant to the disease processes. Ranibizumab did not influence the levels of VEGF-B in the real world. CRT might help to distinguish PCV from nAMD.

Plasma Cytokine Profiles in Patients With Polypoidal Choroidal Vasculopathy and Neovascular Age-Related Macular Degeneration

PURPOSE

The concentrations of cytokines in plasma may be different between neovascular age-related macular degeneration (nAMD) and polypoidal choroidal vasculopathy (PCV). We studied plasma levels of cytokines in patients with nAMD and PCV and compared them with control individuals.

METHODS

This was a prospective, clinic-based, case-control study of treatment-naive participants (n=49) with PCV (n=24), nAMD (n=11), and cataract controls (n=14). We sampled fresh venous blood and isolated plasma for analysis. Plasma concentrations of 34 angiogenic and inflammatory cytokines were determined by Luminex bead-based multiplex array.

RESULTS

After adjusting for gender and age using multivariate logistic analysis, we found that the plasma concentrations of monocyte chemoattractant protein-1, vascular endothelial growth factor (VEGF)-A, and VEGF-D significantly higher in both nAMD and PCV patients than those in controls (all P<0.05, times in nAMD: 3.5, 4.3, and 13.8, respectively, times in PCV: 4.1, 4.0, and 11.5, respectively). In contrast, the plasma concentration of platelet-derived growth factor-BB was significantly lower in nAMD and PCV patients than those in controls (all P<0.05, times in nAMD: 1.6, times in PCV: 1.7). The plasma levels of leukemia inhibitory factor in nAMD group were significantly higher compared with PCV group (P<0.0167).

CONCLUSIONS

Multiple cytokines involved in systemic inflammation and angiogenesis including monocyte chemoattractant protein-1, platelet-derived growth factor-BB, VEGF-A, and VEGF-D may contribute to the pathogenesis of nAMD and PCV. Measurement of leukemia inhibitory factor in the plasma may help differentiate nAMD from PCV. This finding suggests that the 2 disorders may have different molecular mechanisms, and additional longitudinal studies will be needed to determine whether these findings have clinical relevance to influence treatment algorithms or provide novel targets for medical therapy.