AMD DOSING

Irmela Mantel MD

An individually planned treatment regimen for neovascular age-related macular degeneration (nAMD) may offer the potential to significantly reduce the clinical burden of AMD treatment while obtaining good functional results, according to Irmela Mantel MD at the University Eye Hospital Jules Gonin, Lausanne, Switzerland.

“The observe-and-plan regimen significantly improved visual acuity with fewer clinical visits compared to other widely used regimens such as PRN and treat-and-extend,” Dr Mantel told EuroTimes.

“This approach using a planned treatment regimen in an individualised fashion, based on the measurement of an individual’s first disease recurrence interval, reduces the number of clinic visits and injections while still maintaining visual acuity improvements throughout the follow-up period,” she said.

Dr Mantel said that the idea for the observe-and-plan regimen was inspired by first-hand experience of treating nAMD patients. “It became obvious that this pathology with high incidence needed efficient chronic care management because most patients required ongoing treatment with anti-VEGF injections and new patients were continuously added,” she said.

The only regimens available at that time were fixed monthly injections for every patient or PRN retreatment based on monthly visits, said Dr Mantel.

While PRN allowed for reducing the number of injections, the burden for caring institutions, with mandatory monthly visits, remained high. Fixed monthly re-injections, while offering the possibility of skipping visits, was unacceptable due to overtreatment of most patients and high medical cost, she added.

Dr Mantel and co-workers speculated that it might be possible to combine the advantages of PRN (minimum of injections) with the advantages of a fixed regimen (skipping time-consuming visits) if they could determine the optimal individual treatment interval and if this interval was relatively stable over time.

An initial study of 39 patients confirmed the existence of a regular, predictable individual pattern in the need for retreatment with relatively small fluctuations over the follow-up period. Based on these results, the observe-and-plan regimen was developed in order to take advantage of the predictability of individual need for treatment.

After three loading doses of ranibizumab, the disease recurrence interval was determined in monthly observation visits. Retreatment was applied in a series of three injections with individually fixed intervals (two weeks shorter than the recurrence interval), combined with periodic adjustment of the intervals. The allowed injection intervals in treatment plans ranged from one to three months. If there was no recurrence at three months, the patient could change to monitoring alone.

The benefit became rapidly obvious to clinicians and patients, said Dr Mantel, with a mean of less than four monitoring visits (compared to 12 with a PRN regimen or approximately eight with treat-and-extend) and a mean number of injections just below eight during the first year.

“It became easy to cope with a large number of patients, most importantly without compromising the visual results. Forward planning was facilitated, and resources needed were reduced. Those patients, who were included for their second eye after having experienced the PRN regimen with their first eye, were most satisfied with the reduced number of visits. Some of them needed an injection only every three months and a visit every six months. The reduced number of appointments makes a huge difference for our aged patients,” she said.

Dr Mantel and colleagues reported their findings in BJO (2014;98:1192–1196), and Eye (2015;29:450-451).

Irmela Mantel: irmela.mantel@fa2.ch