Safety of Intravitreal Therapies

Abstract

Purpose: To study the safety of intravitreal drug injections used to treat macular eye diseases. Methods: This thesis is based on results from two clinical trials, the BEVORDEX study, a phase II, multicentre, randomised clinical trial of sustained release intravitreal dexamethasone implant (DEX implant) versus intravitreal injections of bevacizumab for diabetic macular oedema (DMO) and the Speed IOP study, a crossover randomised clinical trial which primarily assessed the association of intravitreal injection speed with intraocular pressure (IOP) elevation in patients receiving injections of ranibizumab for age-related macular degeneration. Results: Based on the first year results of the BEVORDEX study, an IOP elevation of at least 5 mmHg from baseline was seen in 46 % of DEX implant treated eyes and 19% of bevacizumab treated eyes, P= 0.008. Four eyes enrolled in the study had cataract surgery and 11% DEX implant treated eyes lost more than 10 BCVA letters. The most frequently reported systemic adverse event was worsening of systemic hypertension. Results from the Speed IOP study showed that the mean IOP elevation at 2 minutes after injection was 18 mmHg and 17.9 mmHg with slow and fast injections, respectively, (P= 0.93). Mean IOP elevation at 2 minutes was 21.6 mmHg in the group of patients who had no reflux and 9.7 mmHg in the reflux group, (P < 0.001); and 19.8 mmHG and 15.5 mmHg in the pseudophakic and the phakic groups respectively, (P= 0.12). Conclusion: Thesis data show that both bevacizumab and DEX implant were well tolerated systemically. However, DEX implant was associated with higher frequency of ocular adverse events. Although intravitreal injection speed and lens status had no significant impact on post-injection IOP elevation, absence of post-injection reflux was significantly associated with IOP elevation.