The Duke Baerveldt 350 Versus Ahmed ClearPath 350 Study (DBACS): A Randomized Control Trial In Adults With Medically Refractory Glaucoma.

Purpose: To compare the efficacy and safety profile of two non-valved glaucoma drainage devices (GDDs).

Patients & methods: In this randomized control trial, patients with medically refractory glaucoma needing surgical intervention were randomized for placement of a Baerveldt 350 (BVT) or an Ahmed ClearPath 350 (ACP). Baseline testing included measures of visual acuity, intraocular pressure (IOP), medication, visual fields, and optical coherence tomography. IOP, medication use, and complications were assessed at post-operative day one, week one, week four, week six, month three, month six, and year one.

Results: A total of 76 subjects were enrolled, 37 randomized to BVT and 39 to ACP. A total of 70 subjects underwent surgery and 61 subjects were seen to one year of follow-up. No significant differences were observed in age, sex, race, eye laterality, glaucoma type, glaucoma severity, prior surgeries, and baseline IOP (p = 0.66, 0.10, 0.70, 0.48, 0.06, 0.65, 0.50, 0.56 respectively), between the groups. At one year, both groups showed significant reductions in IOP, though the ACP group showed lower mean IOP at 12 months (11.4 vs 14.1 mmHg, p = 0.010) as well as a larger IOP decrease compared to baseline (-44.1 vs -30.7%, p = 0.038). Medication usage remained similar in both groups. Complications were infrequent and comparable between the devices. This study did not reach the number of subjects thought to be needed to power the study appropriately; despite the enrollment numbers, statistically significant differences were noted, and no type II occurred for the primary endpoint of mean IOP.

Conclusion: While both GDDs demonstrated efficacy over a 1-year period, ACP showed a lower mean IOP and greater IOP percentage decrease from baseline compared to BVT. Both exhibited low complication rates. Further research over a longer follow-up is warranted to explore the IOP differences.