Studies investigating the Observe and Plan (O&P) protocol showed that it could be used as an individually fixed treatment plan for neovascular age-related macular degeneration (AMD), reducing clinical burdens with a good visual outcome. The first studies showed a high intra-individual predictability of retreatment interval during the first year of treatment and a significantly improved visual acuity after a 2 year follow-up. However reserved were made for patients with late recurrences that may be aggressive and necessitate a dramatic shortening of the retreatment interval. To complete this new clinical approach, O&P should be compared to other AMD protocols. The purpose of our study was to compare the relative efficacy of O&P versus pro re nata (PRN) for the treatment of neovascular AMD.
Name
Observe and Plan contre Pro re nata: etude comparative a 1 an de suivi
Introduction
Patients et Methodes
This was a 1 year follow up open label prospective comparative study that included patients with neovascular AMD confirmed by angiography and spectral domain optical coherence tomography (OCT). Two groups were formed at the inclusion, after three monthly doses of ranibizumab: the first group received an Observe and Plan follow-up and the second a PRN one. The primary outcomes were the mean visual acuity (VA) change, the number of visits and the number of injections after a 1 year follow up.
Résultats
At the inclusion, there were 9 patients in the group O&P and 10 in the group PRN. In the first group 5 patients were lost to follow-up (55%) and 3 in the second group (30%). Among the patient completing the study, the mean visual acuity change was -1,25 letters in group 1 (n=4) and +1,43 letters in group 2 (n=7), while the number of visits was 5,25 in the first group and 7,14 in the second. Then the number of injections was 7 in group 1 versus 6,86 in group 2.
Discussion
Many protocols exist to treat wet AMD, some of them are easier to use in real life than others. It seems that the best results are obtained when the number of injections is the highest. In this study, we observed that many patients did not received the good treatment because of the lost of follow-up. It suggests that the simpliest the protocol is for the patient, the better is the observance.
Conclusion
It is the first study that compares the O&P protocol versus PRN. Our study suggests the difficulty to follow strictly the O&P protocol for the patients and for the ophthalmologist in real life. The O&P protocol needs to be compared in larger studies to PRN or Treat and Extend protocols to determine if it could be an individually balanced protocol between number of visits and number of injections for patients with neovascular AMD