Research Digest

Prostaglandin Efficacy in Randomized Controlled Clinical Trials

A meta-analysis of randomized clinical trials (RCTs) examining the effects of prostaglandins bimatoprost, latanoprost and travoprost on IOP reduction showed that bimatoprost had greater efficacy.¹ However, the incidences of hyperemia were lower for latanoprost and travoprost.

French researchers studied eight RCTs, involving a total of 1,610 patients. Inclusion criteria were prospective, double-masked, randomized controlled clinical trials and patients diagnosed with primary open-angle glaucoma or ocular hypertension; additionally, prostaglandin monotherapy, without systemic/ocular medications or laser surgery that could affect IOP within the past 3 months. The main outcome measures were efficacy assessed by IOP (taken at 8 a.m., 12 p.m., 4 p.m., and 8 p.m.) change at 3 months from baseline and tolerability assessed by the incidence of conjunctival hyperemia.

RCTs up to the end of July 2006 were searched. Quality of the trials was assessed using the Jadad scoring system. Two investigators reviewed 113 potentially relevant RCTs independently to ascertain their appropriateness for inclusion in the analysis, with 105 ultimately excluded. One was on all three of the prostaglandins, four on latanoprost and bimatoprost, two on travoprost and bimatoprost and one on latanaprost and travoprost.

IOP change from baseline was statistically significantly greatest with bimatoprost, compared with latanoprost at all time points [weighted mean (WM) 8 a.m.: WM=0.50 mm Hg; P=0.05; 95% confidence intervals (CIs) 0.01-0.99; 12 p.m.: WM=1.17 mm Hg; P<0.001; 95% CI 0.68-1.66; 4 p.m.: WM=0.78 mm Hg; P=0.003; 95% CI 0.26-1.29; 8 PM: WM=0.67 mm Hg; P=0.04; 95% CI 0.02-1.32], and with travoprost during the daytime (8 a.m. WM=1.02 mm Hg; P=0.004; 95% CI 0.32-1.72; 12 p.m.: WM=0.86 mm Hg; P=0.02; 95% CI 0.12-1.59). Latanoprost and travoprost were comparable in their ability to reduce IOP at all time points (P≤0.82). The incidence of hyperemia was less with latanoprost and travoprost [latanoprost vs. bimatoprost: relative risk=0.59; P<0.001; 95% CI 0.50-0.69; travoprost vs. bimatoprost: relative risk=0.84; P=0.05; 95% CI 0.70-1.00].

"Although this difference in IOP reduction was relatively small," the authors write, "it was maintained at all measured time points and may have some clinical significance. … In terms of tolerability assessment … These findings may be clinically relevant, particularly in patients having side effects and/or poor compliance." OM

1. Aptel F, Cucherat M, Denis P. Efficacy and tolerability of prostaglandin analogs: A meta-analysis of randomized controlled clinical trials. J Glau. Dec. 2008. 17:667-673.

Fibrin Glue vs. Sutures in Pterygium Surgery

Canadian researchers found that the use of fibrin glue (FG) to attach conjunctival autografts in pterygium surgery produced less inflammation than did sutures.¹ The prospective, observer-masked clinical study examined 40 eyes of 40 patients undergoing primary pterygium surgery with conjunctival autograft. In group 1, surgeons used FG to attach the graft, while in group 2, surgeons used sutures. Standardized digital slit-lamp photographs were taken at 1 week, 1 month and 3 months postoperatively, with sutures masked through photo-editing software.

Two masked observers graded the images for degree of inflammation, subconjunctival hemorrhage (SCH) and graft stability. With FG, the researchers found the degree of inflammation "significantly less" than with sutures at 1 month and 3 months. No significant difference was detected for inflammation at 1 week postoperatively. No significant difference was seen in degree of postoperative SCH between the groups at any time point. Additionally, conjunctival grafts secured with FG were as stable as those secured with sutures. OM

1. Srinivasan S, Dolin M, McAllum P, Berger Y, Rootman DS, Slomovic R. Fibrin glue vs. sutures for attaching the conjunctival autograft in pterygium surgery: A prospective observer-masked clinical trial. Br J Oph 2009. 93:215-218.