Treat-and-Extend May Fall Short in Some Macular Degeneration
by: Laird Harrison
Physicians who say they are using a treat-and-extend approach may be undertreating neovascular age-related macular degeneration (nAMD) lesions with a long initial induction to inactivity, researchers say.
In a study of patients with nAMD from a large registry who were being treated with this approach, the mean change in visual acuity after first grading of inactivity was +1.0 letters at 12 months, −0.6 letters at 24 months, and −1.5 letters at 36 months.
“Our data suggest that practitioners who identified themselves as using a treat-and-extend regimen did not necessarily adhere strictly to the principles of treat and extend,” write Rohan W. Essex, MBBS, from the Australian National University in Acton, and colleagues.
They published their findings online July 8 in Ophthalmology.
In clinical trials, the three approved anti-VEGF treatments (ranibizumab, bevacizumab, and aflibercept) have achieved dramatic results.
However, patients and physicians face more challenges outside the rarefied atmosphere of these trials, researchers say. Many patients are elderly or infirm, making it hard for them to get to appointments. And the injections are uncomfortable and expensive.
In addition, some worry that the incidence of lesion-associated atrophy may be higher in those treated monthly than in those treated less frequently.
Thus clinicians often look for ways to reduce the burden on patients. As reported by Medscape Medical News , a recent survey of the members of the American Society of Retina Specialists found that only 1.5% inject their patients monthly, regardless of the condition of their lesions, the protocol used in clinical trials. The largest proportion, 64.8%, treat until the disease is inactive and then extend the time between treatments, a protocol known as “treat and extend.”
To evaluate this approach, Dr Essex and colleagues analyzed data from the Fight Retinal Blindness registry, a voluntary record of routine clinical practice in Australia, including treatment decisions, visit schedules, and grading of lesion activity.
At each visit, clinicians used funduscopy, optical coherence tomography, and sometimes fluorescein angiography to determine whether lesions were active. The clinicians participating in the registry and current study agreed that lesions were active if they had “features such as sub- or intra-retinal fluid, or new haemorrhage, that suggested that the [choroidal neovascularization] lesion was active.”
Although they did not agree to a common definition of treat-and-extend, the researchers assumed that such protocols included monthly treatment during an induction phase until the lesions were inactive, increased treatment intervals when the disease is inactive, and decreased treatment intervals when the disease is active……
Read more: http://www.medscape.com/viewarticle/867993