Treat-and-Extend Approach With Ranibizumab Effective in AMD

By David Douglas

January 23, 2020

NEW YORK (Reuters Health) - In patients with neovascular age-related macular disease, a treat-and-extend ranibizumab regimen is not inferior to injections given at fixed intervals, plus it's more convenient, according to a new clinical trial.

"Our goal in treating macular degeneration, the most common cause of blindness in the western world, is to maximize visual gains and minimize the burden of treatment and visits on patients and their families," Dr. Peter J. Kertes of Sunnybrook Health Sciences Centre, in Toronto, Canada, told Reuters Health by email.

"This most recent Canadian Treat and Extend Study (CanTreat) publication," he added, "shows definitively that patients randomized to a treat-and-extend regimen had similar outcomes to those randomized to monthly treatment at 24 months."

Dr. Kertes and colleagues assigned 580 patients with treatment-naive choroidal neovascularization secondary to AMD to receive intravitreal ranibizumab 0.5 mg either in a treat-and-extend or monthly dosing regimen.

At 24 months, 466 (80.3%) of the participants had completed the study, the team reports in JAMA Ophthalmology. The treat-and-extend group had received a mean of 17.6 injections compared with 23.5 in those in the monthly group.

The mean best-corrected visual acuity (BCVA) improvement in the treat-and-extend group was 6.8 letters versus 6.0 letters in the monthly group.

There was a gain of 15 or more letters in 25.5% of the treat-and-extend group and 23.1%o of the monthly treatment patients. For loss of 15 or more letters, the proportions were 6.5% and 5.8%, respectively.

"Most patients responded well to the stepwise extension regimen," the researchers write. "At 24 months, 73.7% of patients were able to extend the treatment interval to 8 or more weeks and 43.1% to 12 weeks."

A regimen with fewer injections and visits, they add, "has the potential to increase convenience and reduce cost to the health care system compared with monthly dosing."

To better understand the long-term outcome of such a regimen the study has been extended to 36 months, the team notes.

Dr. Mark Gillies, a professor of ophthalmology at the University of Sydney, Australia, told Reuters Health by email, "This study is significant because it provides the strongest evidence yet that the treat-and-extend regimen of VEGF inhibitors, which is now the commonest way to use them, can give outcomes for neovascular AMD that are as good as those from the more frequent dosing that was used in the pivotal clinical studies."

"This important issue had not been addressed previously by a formal, 2-year randomised clinical trial," added Dr. Gillies, who was not involved in the trial.

SOURCE: JAMA Ophthalmology, online January 9, 2020.