Inclisiran administration potently and durably lowers LDL-C over an extended-term follow-up: the ORION-8 trial.

BACKGROUND AND AIMS:Data describing the long-term efficacy, safety, and tolerability of inclisiran are limited. This was explored in ORION-8, an open-label extension study of preceding Phase 2 and Phase 3 placebo-controlled and open-label extension trials. METHODS:Adults with ASCVD, ASCVD risk equivalent, or HeFH received open-label inclisiran every 180 days (after completion of the parent trial) until Day 990, followed by an end-of-study (EOS) visit at Day 1080 or ≥90 days after last dose. Study endpoints included proportion of patients achieving pre-specified LDL-C goals (ASCVD: <1.8 mmol/L [<70 mg/dL]; ASCVD risk equivalent: <2.6 mmol/L [<100 mg/dL]), percentage and absolute changes in LDL-C at EOS, and safety of inclisiran. RESULTS:Of 3274 patients included in the analysis, 2446 (74.7%) were followed until EOS. Mean age was 64.9±9.9 years, 82.7% (n=2709) had ASCVD, and mean baseline LDL-C was 2.9±1.2 mmol/L. Mean cumulative exposure to inclisiran (including parent trials) was 3.7 years; maximum exposure was 6.8 years. With inclisiran, 78.4% (95% CI: 76.8, 80.0) of patients achieved pre-specified LDL-C goals and mean percentage LDL-C reduction was -49.4% (95% CI: -50.4, -48.3). No attenuation of LDL-C lowering over time was observed. Treatment-emergent adverse events at the injection site (all mild or moderate) occurred in 5.9% of inclisiran-treated patients. Inclisiran-associated anti-drug antibodies were infrequent (5.5%) and had no impact on the efficacy or safety of inclisiran. No new safety signals were identified. CONCLUSIONS:In the largest and longest follow-up to date, inclisiran demonstrated sustained and substantial LDL-C lowering with a favourable long-term safety and tolerability profile. ClinicalTrials.gov identifier: NCT03814187.