Translational public health care perspective: Intravitreal treatment of neovascular age‐related macular degeneration has revolutionized clinical ophthalmology

T he experience with high-volume treatment of neovascular agerelated macular degeneration with intravitreally injected inhibitors of vascular endothelial growth factor is approaching a decade. It is therefore time to assess whether the promising results found in the clinical trials that led to approval of the then new class of pharmaceutical products have lived up to their promise and delivered results that are detectable on a population level after their introduction in routine clinical practice. Documented declines in the incidence of blindness show a dramatic change over the past 10 years (Bloch et al. 2012; Skaat et al. 2012). The implementation of treatment with antivascular endothelial growth factor has been a great challenge. One of the means of tackling it, in addition to the massive use of optical coherence tomography as an alternative to fluorescein angiography, has been to use specially trained nurses to perform intravitreal injections. This innovation is controversial in some settings because it disrupts traditional barriers between professions and because the choice of practice is confounded by reimbursement and status issues. In this issue of Acta Ophthalmologica, Hasler and associates document the safety of the intravitreal injection procedure used at their clinic and show that it can be compared with large clinical trials (Hasler et al. 2014). The results are confirmed by an independent study, which is also reported in this issue (Asten et al. 2014), and the new studies lend support to two previously published studies from the United Kingdom (Dacosta et al. 2014; Michelotti et al. 2014). The verdict is clear: the safety of intravitreal injection of vascular endothelial growth factor inhibitor by nurses or physicians in the early stage of ophthalmology training is as safe as injection by fully trained ophthalmology specialists. It should be noted that the documentation that it is safe to let nurses perform intravitreal injections was demonstrated for high-volume centres where the staff has been trained specifically for this purpose, where standardized procedures are strictly adhered to and where injections are given in dedicated injection rooms or operating theatres. Under these circumstances, it may indeed be safer to inject than in outpatient clinics and offices (Abell et al. 2012; Hasler et al. 2014). Surveys of clinical outcomes after one and 2 years in patients with neovascular age-related macular degeneration treated with antivascular endothelial growth factors using a discontinuous regimen guided by optical coherence tomography in general show poorer efficacy than in clinical trials, which can largely be attributed a lower injection frequency (Bandukwala et al. 2010; Martin et al. 2012; Chakravarthy et al. 2013; Cohen et al. 2013; Finger et al. 2013; Asten et al. 2014). Thus, there is a definite need to consider how the treatment can be better implemented. We find that training nurses to perform intravitreal injections and assist in monitoring patients is an effective means of providing more time for physicians to diagnose disease and monitor treatment in busy medical retina clinics. A majority of the studies of daily clinical practice have a pragmatic relationship to treatment guidelines, are limited by retrospective designs and have different approaches to how they report patients that are lost to follow-ups. Consequently, a direct comparison between studies is made difficult by differences in design. Studies evaluating different treatment strategies have been and are being investigated (Fung et al. 2007; Abraham et al. 2010; Larsen et al. 2012; Ophthotech Corp 2013; Berg et al. 2015); furthermore, an alternative antivascular endothelial growth factor to the conventional and first approved drug (ranibizumab) has been approved to prolong the intervals between follow-ups and in between injections to meet the logistic burden of monthly examinations (Heier et al. 2012). The prevention of subretinal fibrosis and atrophic scars, shown to be amajor cause of vision loss in patients treated with antivascular endothelial growth factors, is also of interest in innovative experimental research to improve long-term outcomes in the treatment of neovascular AMD (Bloch et al. 2013; Ophthotech Corp 2013; Daniel et al. 2014). In summary, there is a pipeline of new drugs that target different growth factors in the eye when administered locally, all of which aim to improve and prevent visual impairment in