Amarin are simply running a large outcomes trial (SPA accepted by the FDA) to try and mirror as best they can the patient subset in JELIS that showed a 53% RRR in CVE's. R-IT has been designed and tweaked to give the best possible chance for the JELIS subset trial results to be replicated in a western population. Is that simple enough for you?
Meanwhile, a google scholarly article search for "JELIS trial Lancet" gets 2,730 hits - meaning JELIS papers have been published in multiple journals, and cited in many, many more.