A randomized phase II trial of interferon-alpha 2b versus 5-fluorouracil after trabeculectomy

Purpose: The aim of the present study was to investigate the safety and pot ential efficacy of subconjunctival interferon-alpha 2b (IFN-a), either aton e or in combination with 5-fluorouracil (5-FU), in reducing the risk of fai lure of glaucoma surgery Methods: A prospective, masked randomized phase ii study was undertaken in which patients received three subconjunctival injections per week for 3-4 w eeks postoperatively. Three treatments were compared: (i) IFN-alpha (1 x 10 (6) IU per dose); (ii) 5-FU (5 mg per dose); and (iii) alternating IFN-alph a and 5-FU (BOTH). The primary outcome measures were: (i) rate of successfu l control of intra-ocular pressure without further surgery; and (ii) the in cidence of side effects. Results: Fifty-seven patients undergoing glaucoma surgery with an increased risk of failure were evaluated, including 23 patients (40%) undergoing tra beculectomy combined with extracapsular cataract extraction as well as othe r conventional high-risk groups. With 53 patients (93%) completing 2 years follow up, there was no significant difference in success rates among the t hree groups. Intra-ocular pressure was controlled without further surgery i n 79% of patients (95% confidence interval (CI): 61, 97%) receiving IFN-alp ha, in 89% of patients (76, 100%) receiving 5-FU and in 89% of patients (76 , 100%) receiving BOTH. Side effects were similar among the three groups. Conclusions: These results are consistent with a beneficial effect of IFN-a lpha 2b given either alone or in combination with 5-FU after glaucoma filte ring surgery. However; the lack of a clear and substantial benefit over con ventional anti-fibrotic therapy does not support the further clinical evalu ation of these treatments.