麻豆传媒

NEW ORLEANS -- Two poster sessions that spanned 4 days of the American Academy of Ophthalmology meeting provided new data about the natural history and management of age-related macular degeneration (AMD). The following summaries represent just a few of the highlights.

Natural History of AMD: 20-Year Follow-up

Fewer than 20% of eyes with early AMD at diagnosis progressed to advanced disease, as compared with half or more of eyes with intermediate AMD followed for 20 years, reported investigators at the National Eye Institute in Bethesda, Maryland.

Using a 9-step AMD severity scale, found that 18.3% of 179 eyes with early (steps 1-3) AMD progressed to advanced disease. That represented almost a fourfold increase compared with previous studies show progression rates <5% at 10 years in eyes with early AMD at the start of follow-up.

In the group with moderate AMD at baseline, progression to advanced AMD occurred in 45% of 108 eyes with AMD steps 4-6 and 59% of 34 eyes with AMD steps 7-9. The rates were consistent with those of earlier studies involving larger cohorts followed for 10 years.

"These results demonstrate that AMD pathology, once definitively present, tends to progression continuously with time over the long term," Chandana Papudesu, BS, and co-investigators concluded.

Anti-VEGF Benefits Persist Long Term

Patients with neovascular AMD continued to benefit from anti-VEGF therapy after receiving ≥50 intravitreal injections of the agents, long-term follow-up from a retina specialty clinic showed.

Clinical management with a treat-and-extend regimen led to a mean visual gain of 9.7 letters after the 50th injection and 8.7 letters after 8 years of follow-up for 67 patients and a total of 71 treated eyes, reported Sean D. Adrean, MD, of Retina Consultants of Orange County in Fullerton, California. About 10% of eyes lost more than 3 lines of visual acuity, and more than a third gained at least three lines over the 8-year follow-up.

The study had a broad inclusion criteria, as compared with clinical trials, and probably better reflected typical visual outcomes in clinical practice, Adrean and colleagues noted. The study population included patients with good and poor vision, small and large areas of central neovascularity, and with and without complicating factors such as subretinal hemorrhage or tears of retinal pigment epithelium.

Despite the treat-and-extend objective, the interval between injections decreased modestly from 5.4 weeks and 9.6 injections during the first year to 6.4 weeks and 8.1 injections during the last year of follow-up.

Vision Preserved with Extended Intravitreal Injection Interval

Extending the interval between injections of anti-VEGF agents to 12 weeks or longer did not adversely affect clinical benefits obtained during a year of treatment at 4- to 8-week intervals, a retrospective analysis of two clinical trials showed.

In the VIEW randomized trials, patients received intravitreal injections of ranibizumab (Lucentis) at 4 week intervals and two different doses of aflibercept at 4 or 8-week intervals for 52 weeks. During the second year of follow-up, the injection interval was extended to ≥12 weeks for some patients. The retrospective analysis compared results with the different injection intervals, as reported by Rahul Khurana, MD, of Northern California Retina Vitreous Associates in Mountain View.

The analysis included approximately 1,500 randomized patients. In the ranibizumab arm, 42.5% of patients received intravitreal injections at intervals ≥12 weeks, as did 53.9% and 47.9% of the two ranibizumab groups. Among patients in the ≥12-weeks group, best corrected visual acuity (BCVA) improvement at 52 weeks were 8.7, 9.9, and 9.7, letters in the ranibizumab and aflibercept arms. The 52-week gains in the <12-week group were 10.3, 9.7, and 8.9 letters in the respective treatment arms.

The gains observed at 52 weeks were preserved at 96 weeks in all three treatment arms, said Khurana. For the ≥12 weeks subgroup, the mean BCVA at 96 weeks was 8.5, 8.8, and 9.2 letters for the ranibizumab arm and two aflibercept arms. The 96-week results for the <12-week subgroup were 9.1, 7.7, and 8.1 letters.