Combined Treatment with Bevacizumab and 5-fluorouracil Attenuates the Postoperative Scarring Response After Experimental Glaucoma Filtration Surgery

Purpose: This study evaluated the use of combined bevacizumab with 5-fluorouracil (5-FU) on postoperative scarring and bleb survival after experimental glaucoma filtration surgery in comparison to the agents alone.

Methods: Filtration surgery was performed on 26 female New Zealand White rabbits. The rabbits were allocated to one of four treatments: 5-FU combined with bevacizumab, 5-FU alone, bevacizumab alone, or phosphate buffered saline (PBS). The subconjunctival injections were administered immediate postoperatively and weekly for 3 weeks. Clinical assessment and bleb photography were performed. Histologic staining determined the presence of subconjunctvial fibrosis and mRNA expression of collagen I and fibronectin in the tissue was quantified.

Results: Bevacizumab in combination with 5-FU resulted in a greater antifibrotic effect compared with monotherapy with 5-FU or bevacizumab alone, as evidenced by the attenuation in fibronectin and mature collagen I expression and deposition (P < 0.05). In addition, this was associated with a 100% bleb survival at day 28 in the combined treatment group compared with monotherapy (50% bevacizumab [P < 0.05] and 25% 5-FU [P < 0.001]). Conjunctival vascularity significantly reduced with bevacizumab treatment both alone and in combination with 5-FU.

Conclusions: The results provide compelling evidence that combined bevacizumab and 5-FU offers superior antifibrotic effect over monotherapy in a model of glaucoma filtration surgery, while prolonging bleb survival at the same time. A synergistic effect is suggested to be present.