ORION-3 extended the ORION-1 trial
The ORION-1 study was a phase 2 placebo-controlled, dose-ranging safety and efficacy assessment of inclisiran that gave patients two injections of the drug, at day zero and 90 days, and followed them for an additional 120 days (210 days total follow-up duration), and in some cases for as long as 360 days total. Of the 370 patients who received inclisiran in ORION-1, 290 agreed to continue inclisiran in the open-label extension, ORION-3. ORION-1 also included 127 patients randomized to initial placebo treatment, and 92 of these patients agreed to continue in ORION-3 and became the patients initially treated with evolocumab injections every other week for 1 year followed by initiation of an inclisiran regimen.
The primary outcome of ORION-3 was the change in LDL-C from baseline (the ORION-1 baseline) after 210 days of receiving inclisiran in ORION-3 (or a total of roughly 570 days after the start of ORION-1). The primary endpoint showed that, at day 210 of ORION-3 the average reduction in LDL-C from the original baseline level was 47.5%.
But a “more important” outcome, said Dr. Ray when he first reported the ORION-3 results during the American Heart Association scientific sessions in Chicago in November 2022, was that, overall, during 4 years on inclisiran this cohort showed an average cut in LDL-C from baseline of about 45% that consistently remained at this level throughout the 4 years of treatment.
“This provides us with an idea of what happens with chronic inclisiran dosing,” Dr. Ray explained. “There was no loss of biological efficacy, and we achieved these clinically meaningful, time-averaged reductions with a good safety profile. The great thing is that when patients get their injections [every 6 months] you see a consistent LDL-C reduction. A twice-annual injection is an opportunity to redesign” the way patients receive preventive cardiology care and treatment to lower LDL-C, Dr Ray said.
ORION-1 was sponsored by The Medicines Company. ORION-3 was sponsored by Novartis (which acquired The Medicines Company). Dr. Ray has received consulting fees, personal fees, and research grants from Novartis, as well as consulting fees and research grants from Amgen, the company that markets evolocumab (Repatha), and research grants from Regeneron, the company that markets alirocumab (Praluent). He has also received consulting fee, personal fees, and research grants from numerous other companies. Dr. Rosenson has been a consultant to and has received research funding from Amgen, Novartis, and Regeneron, and he has received speaking fees from Amgen and Regeneron, and has ties to several other pharmaceutical companies.
This article was updated on 1/26/2023.