CABERNET study does not meet primary endpoint at 2 years

Pravin U. Dugel

MIAMI — Visual acuity results for epimacular brachytherapy to treat wet age-related macular degeneration did not meet a study's primary endpoint at 2 years, a presenter here reported.

The phase 3, multicenter, prospective, randomized CABERNET (CNV secondary to AMD treated with beta radiation epiretinal therapy) study included a treatment arm of 302 patients receiving strontium-90 epimacular brachytherapy (NeoVista) and two mandatory Lucentis (ranibizumab, Genentech) injections, followed by as-needed injections. The control arm consisted of 155 patients receiving ranibizumab on a modified PIER protocol with 10 mandatory injections.

"The bottom line... is that the CABERNET study did not achieve its endpoint with a 10% non-inferiority margin," Pravin U. Dugel, MD, said at Angiogenesis, Exudation and Degeneration 2012.

The treatment group required roughly six injections and demonstrated a mean 2.5 letter loss over 24 months, while the control group required approximately 11 injections and achieved a mean 4.4 letter gain. The difference in adverse events for the two groups was not significant. Ten patients had suspected radiation-based retinopathy.

"The CABERNET study did demonstrate an acceptable safety profile for epimacular brachytherapy at the 2-year mark, and it did find a subgroup of patients that tended to respond well with this device," Dr. Dugel said.

Whether this subgroup of patients can be reliably and consistently identified in clinical practice is not yet known, he added.

"At the end of the day, I think it is important to keep this study in its proper perspective. It was started in 2006 when there were few treatment alternatives. In retrospect, the CABERNET study should not have included treatment-naïve patients. ... The CABERNET study should have [also] placed a lot more importance on probe placement," Dr. Dugel said.

Disclosure: Dr. Dugel is a consultant to and minor shareholder of NeoVista.