This year the American Society of Retina Specialists’ Annual Meeting was held in Maui, Hawaii from October 10th to 15th. It was well-attended and provided an excellent overview of the recent advancements in our field.
Age-related macular degeneration
The first session was devoted to treatment of age-related macular degeneration (AMD). Jason Slakter, MD, presented the one year outcomes of the VEGF-trap phase 2 trial for wet AMD, in which patients were randomized to receive VEGF-Trap-Eye 0.5 mg or 2 mg monthly, or 0.5, 2 or 4 mg quarterly for 12 weeks followed by prn use thereafter. All groups had reduction in choroidal neovascular membrane (CNV) size on optical coherence tomography (OCT) and fluorescein angiography at week 32, and tolerated the drug well.
The safety results of several phase 1 clinical trials for AMD were presented. Richard Kaiser, MD discussed intravitreal Platelet-Derived Growth Factor (PDGF-BB) in combination with intravitreal ranibizumab. There were no safety concerns, and preliminary data showed regression of CNV. Jeffrey Heier, MD discussed the phase 1 results of intravitreal JSM6427, a small molecule antagonist of integrin a5b1. There were no adverse events in the first 3 cohorts, but he did note that the half-life of the current formulation was short, at 17 hours, indicating the need for development of a sustained release formulation. Sophie Bakri, MD presented the results of the Assessment of Safety for POT-4 (ASaP) trial. POT-4 is a C3 complement inhibitor. Several days after intravitreal injection of a high dose, it forms spherical gel-like deposits in the vitreous, which then releases the POT-4 over 3 to 6 months. In the cohorts treated (up to 450 mcg) here have been no safety concerns.
There were several papers on ranibizumab. Carl Awh, MD, presented the year 1 results of the HORIZON extension trial. Patients in this trial had completed the 2-year MARINA, ANCHOR or FOCUS trials, and for the third year (in the HORIZON trial) received prn ranibizumab 0.5 mg. The visual acuity in that third year declined after the less frequent prn dosing: in the 481 patients, whose vision had increased from 20/80 to 20/50 during the initial 2-year trial, median vision decreased by 1 line to 20/63 at the end of year 1 of HORIZON. Philip Ferrone, MD reported the subgroup analysis of cohort 1 of the SAILOR trial, in which he evaluated the efficacy of ranibizumab according to baseline vision and central foveal thickness (CFT). As baseline vision decreased, the degree of visual improvement increased and CFT improvement was more pronounced. As baseline CFT increased the degree of visual improvement increased modestly and CFT reduction was more pronounced. Bailey Freund, MD, investigated the conversion rate from dry to wet AMD in the fellow eye of patients treated with 0.3 mg, 0.5 mg ranibizumab and control (PDT or sham) in the ANCHOR and MARINA studies. He found no evidence that monthly ranibizumab provides a protective effect in the fellow, untreated eye. Neil Bressler, MD, emphasized the importance of treating with ranibizumab in the worse-seeing eye, as it may become the better-seeing eye if the fellow eye loses vision. Jonathan Prenner, MD, found that patients with CNV > 50% blood (not typically included in clinical trials) responded well to ranibizumab, in terms of resorption of blood (on average to 10% of the lesion) and improvement of visual acuity from 20/200 to 20/160 after 3 monthly injections.
Tom Chang, MD, compared the remission intervals in patients treated with ranibizumab versus bevacizumab for CNV due to AMD, after compiling data from several centers. After 3 consecutive monthly injections of either drug, the time to recurrence of CNV on OCT was 6.6 months for bevacizumab-treated patients and 3.8 months for ranibizumab-treated patients.
There was further data on combination therapies using photodynamic therapy for wet AMD. Subhransu Ray, MD, presented results of the PDEX II trial, which compared combination therapy using reduced fluence PDT, intravitreal dexamethasone 500 mcg and intravitreal ranibizumab 0.5 mg, to monthly ranibizumab. He found that patients receiving the triple therapy needed fewer treatments than 12 per year. Sophie Bakri, MD reported the results of 31 patients receiving triple therapy using reduced fluence PDT, intravitreal dexamethasone 200 mcg and intravitreal bevacizumab 1.25 mg. This was a retrospective series which consisted of real world, rather than clinical trial data, where patients received variable, rather than monthly followup. In all patients, retreatment was given with a mean of 2.3 anti-VEGF injections and 0.3 repeat triple therapy treatments throughout followup. Treatment-naïve patients needed fewer retreatments, with a mean of 0.8 anti-VEGF injections and 0.3 repeat triple therapy treatments throughout followup. Vision was stable or improved, and OCT data showed reduced CFT at 1 year. Albert Augustin, MD reported on triple therapy results using PDT with a reduced light dose, followed 16 hours later by a limited vitrectomy, dexamethasone 800 mcg and bevacizumab 1.5 mg. Patients were followed up every 6 weeks, and approximately one third of patients needed an additional bevacizumab injection or repeat triple therapy. Visual acuity increased by a mean of 1.82 lines at a mean followup of 74 weeks.
Keye Wong, MD, reported that after anti-VEGF injections, vision may continue to improve after the OCT becomes dry, and it may be reasonable to continue injections after the OCT becomes dry. Leonard Feiner, MD analyzed the incidence of RPE tears from the MARINA, ANCHOR and PIER data and found that there was no causality between ranibizumab and RPE tears. Clement Chan, MD, from a multicenter retrospective study, found that RPE height and volume were reliable predictors for RPE tears.
David Brown, MD reported the results of the phase II study of the Neovista Strontium-90 brachytherapy in combination with intravitreal bevacizumab and a limited vitrectomy, in which 34 patients were enrolled. At 12 months, visual acuity and OCT thickness improved, with 38% of patients gaining > 15 letters. Patients had a minimum of 2 bevacizumab injections and were then treated prn at the investigator’s discretion.
The vitreoretinal field continues to evolve, and this year’s ASRS was once again an excellent forum for discussion of the best therapies and techniques to treat our patients. We look forward to further refinement of these treatments, and hope to hear more next year!
Forward to "Part 2 -- CRVO, DME, Trials, Techniques and Awards"
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