Stoekenbroek, Robert M.

Abstract Introduction Statin-associated side effects prevent a substantial proportion of patients from being adequately treated with statin therapy and achieving adequate LDL-C reductions. Phase 3 trials showed that inclisiran, a new siRNA, durably lowers LDL-C by ≥50% on top of maximally tolerated statin therapy. Purpose To evaluate inclisiran's tolerability and LDL-C lowering effects among individuals who were not receiving statin therapy mainly because of statin intolerance. Methods The Phase 3 ORION-10 and ORION-11 trials randomized patients with established ASCVD (or risk-equivalents) with LDL-C >70 mg/dl despite maximally tolerated statins to inclisiran or placebo (1:1). Inclisiran sodium 300 mg was administered s.c. at baseline, three months later, then every six months. The primary efficacy endpoints were % change in LDL-C from baseline to Day 510 and time adjusted % change in LDL-C from baseline after Day 90 and up to Day 540. Absolute LDL-C reductions were secondary endpoints. This analysis included individuals who were not on statin therapy at baseline. Results The trials included 252 (7.9% of the pooled trial populations; mean age 68; male 62%; lipid-lowering therapy 28%). AE rates and LDL-C reductions are shown in the Table. Overall, 12 (4.7%) patients had myalgia (4.8% in the inclisiran groups, 4.7% in the placebo groups). There were 8 discontinuations in the inclisiran groups (6.5%) and 3 in the placebo groups (2.3%). The placebo-adjusted mean reduction in LDL-C at Day 510 was 45.8%, an absolute reduction of 68.0 mg/dL (p<0.0001). Conclusion Among statin intolerant individuals in ORION-10 and 11, inclisiran potently and durably lowered LDL-C with an adverse event profile comparable to placebo. Inclisiran may represent a new and potent therapeutic option for patients with elevated LDL-C unable to tolerate statins. Funding Acknowledgement Type of funding source: Private company. Main funding source(s): The Medicines Company

Abstract Introduction Inclisiran, an investigational siRNA, has been shown to effectively and durably lower LDL-C in Phase 3 trials. Inter-individual variability in LDL-C reductions has been documented for statin therapy and ezetimibe. Purpose To evaluate the inter-individual variability in LDL-C lowering with inclisiran. Methods The Phase 3 ORION-10 and ORION-11 trials randomized patients with established ASCVD (or risk-equivalents) who had LDL-C >70 mg/dl despite maximally tolerated statins to inclisiran or placebo (1:1). Inclisiran sodium 300 mg was administered s.c. at baseline, three months later, then every six months. Co-primary endpoints were the LDL-C reduction from baseline to Day 510 and the time adjusted average % change in LDL-C reduction after Day 90 and up to Day 540. Measures of response variability were pre-specified secondary endpoints. This analysis examines the inter-individual variability of LDL-C reductions at day 510 using pooled data from both trials. Results The analysis included 3178 individuals (92% on statins). At Day 90, 97% of inclisiran-treated patients had an LDL-C reduction. At Day 510, the median percent reduction in LDL-C levels from baseline was 57.3% in the inclisiran group (interquartile range, 44%-70%). An LDL-C reduction ≥50% was reached by 1359 (86.6%) inclisiran-treated patients versus 97 (6.2%) placebo patients at any visit (odds ratio [OR] 97.6, 95% confidence interval [CI] 76–126). An LDL-C reduction ≥30% was reached by 1523 (97.0%) inclisiran-treated patients versus 371 (23.7%) placebo patients (OR 104.5, 95% CI 76–143). At Day 510, 921 patients (65.1%) in the inclisiran group had a reduction ≥50% in LDL-C compared to 34 patients (2.4%) in the placebo group, and 1228 (86.8%) had a reduction ≥30% compared to 148 (10.5%), respectively. Among placebo-treated patients, there was a substantial proportion with notable increases in LDL-C at Day 510 (figure). Conclusion In Phase 3 trials, inclisiran on top of maximally tolerated statins provided reliable, consistent and durable reductions in LDL-C. A large percentage of subjects randomized to inclisiran achieved substantial reductions (>50%) in LDL-C and nearly all achieved at least a 30% reduction suggesting inclisiran is potentially a promising novel therapy for patients needing sustained LDL-C reductions. Waterfall plot of pooled trials Funding Acknowledgement Type of funding source: Private company. Main funding source(s): The Medicines Company

Abstract Introduction Elevated triglyceride (TG) levels contribute to the total burden of circulating atherogenic lipoprotein levels and are associated with increased cardiovascular (CV) risk. LDL-C underestimates risk in patients with elevated TG. Therefore, 2019 ESC/EAS guidelines recommend apoB or non-HDL-C as secondary lipid goals for patients with TG >150mg/dL. Purpose To assess the impact of inclisiran on apoB and non-HDL-C goal attainment across a range of TG levels among patients with atherosclerotic CV disease (ASCVD). Methods The ORION-10 and ORION-11 trials included 3178 patients with ASCVD and LDL-C >70mg/dl despite maximally tolerated statins randomized to inclisiran or placebo (1:1). Pre-specified secondary endpoints were placebo-corrected changes in lipids at Day 510. For this analysis patients were stratified by TG quartiles at baseline within each trial. The proportion of individuals attaining apoB <55 mg/dL or non-HDL-C <70mg/dl within each trial were assessed across TG strata and the likelihood of goal attainment within TG strata assessed using logistic regression. Results In ORION-10, TG quartiles were ≤94, 94 to ≤128, 128 to ≤181 and >181mg/dl respectively and in ORION-11 corresponding values were ≤101, 101 to ≤135, 135 to ≤183 and >183mg/dl. As compared to placebo a significantly greater proportion of patients randomised to inclisiran attained apoB goals within each TG strata (Table). Similar results were observed for non-HDL-C. Conclusion Among patients with ASCVD on maximally tolerated statin and high TG levels, attainment of apoB and non-HDL-C secondary lipid targets was more likely with inclisiran than placebo. Inclisiran may be a useful therapeutic option for patients with atherogenic dyslipidaemia. Funding Acknowledgement Type of funding source: Private company. Main funding source(s): The Medicines Company

Abstract Aims Small-interfering RNA (siRNA)-based targeting of proprotein convertase subtilisin/kexin type 9 (PCSK9) represents a novel therapeutic approach that may provide a convenient, infrequent, and safe dosing schedule to robustly lower low-density lipoprotein cholesterol (LDL-C). Given the long duration of action, however, establishing safety in particular with respect to immunogenicity is of paramount importance. In earlier clinical studies of other RNA-targeted treatment approaches (antisense oligonucleotide therapy) immunological and haematological adverse effects, in particular thrombocytopenia and pro-inflammatory effects, have been reported. Here, we present the pre-specified safety analysis from ORION-1 evaluating platelets, immune cells, immunological markers, antidrug antibodies, and clinical immunogenicity adverse events (AEs) under PCSK9 siRNA treatment with inclisiran. Methods and results The pre-specified safety analysis from ORION-1 was performed in six different inclisiran dosing regimens in patients at high risk of cardiovascular disease with elevated LDL-C levels. Patients received either a single dose (SD: 200 mg, n = 60; 300 mg, n = 62 or 500 mg, n = 66) or double-dose starting regimen (DD: 100 mg, n = 62; 200 mg, n = 63; or 300 mg, n = 61 on days 1 and 90) of inclisiran or placebo (SD: n = 65; DD: n = 62). The effects of inclisiran on haematological parameters including platelet counts, lymphocytes, and monocytes as well as on the immune markers interleukin 6 (IL-6) and tumour necrosis factor-α (TNF-α) were examined after 180 days. Immunogenicity was further evaluated by analysis of anti-drug-antibodies (ADAs) towards inclisiran in 6068 study samples and by careful analysis of immunogenicity AEs as part of the pharmacovigilance strategy. At day 180, no significant alterations of platelet counts were observed in any of the dosing groups (change from baseline, SD: 200 mg: 0.8%; 300 mg: −0.5%; 500 mg: −1.8%; DD: 100 mg: 1.3%; 200 mg: −0.5%; 300 mg: 1.0%; no significant difference for any group as compared with placebo). No significant effects on other immune cells, including leucocytes, monocytes, or neutrophils were detected. Notably, no significant increase of inflammatory biomarkers (IL-6 or TNF-α) with either the SD or DD regimen became evident. There was no evidence for immunogenicity based on ADA level analysis and careful review of clinical immunogenicity AEs in none of the treatment regimens. Conclusion In this pre-specified safety analysis of ORION-1 for the siRNA therapeutic inclisiran, no adverse effects on measures of inflammation or immune activation nor adverse effects on platelets or clinical immunogenicity AEs were observed over at least 6-month treatment. These safety findings in the largest analysis of an RNAi study in humans to date provide strong reassurance about the safety of inclisiran and the potential of cardiovascular RNA-targeted therapies.

Abstract Background PCSK9 inhibitors and statins both lower LDL-C by increasing LDL-receptor (LDLR) function. PCSK9 inhibitors lower Lp(a) by 20–30%, whereas statins do not lower Lp(a). The mechanism by which PCSK9 inhibitors lower Lp(a) is unclear. We assessed the role of the LDLR in Lp(a) reductions produced by inclisiran, an siRNA which prevents hepatic synthesis of PCSK9. Methods ORION-1 was a phase 2 trial of inclisiran in subjects at high ASCVD risk with elevated LDL-C on optimized statin therapy. Subjects received one dose of inclisiran (200, 300, or 500 mg) or two doses at days 1 and 90 (100, 200, or 300 mg). We assessed the correlations between % change in Lp(a) and LDL-C at Day 180 for the inclisiran groups using Spearman correlation coefficients. We additionally assessed the correlation between % change in Lp(a) and absolute change in LDL-C as a proxy for LDLR expression. Lp(a) was measured using an isoform-independent assay and LDL-C with β-quantification. Results ORION-1 included 501 subjects; mean age 63; 65% male; 73% on statins. Median baseline Lp(a) was 37.0 nmol/l (IQR: 11.5–142.0 nmol/l), median LDL-C was 117.0 (IQR: 92.5–149.5 mg/dL). Inclisiran dose-dependently lowered Lp(a) by 14% to 26%. Overall, there was a significant but weak correlation between % change in Lp(a) LDL-C (Spearman coefficient 0.35, p<0.001). This correlation appeared to be stronger at higher inclisiran doses and with repeat dosing (table), as well as in statin-users versus non-users (Spearman coefficient 0.37 vs. 0.21). The correlation between % Lp(a) change and absolute LDL-C change was weaker (0.27, p<0.001). Correlation coefficients LDL-C – Lp(a) Single-dose groups Two-dose groups Inclisiran overall 200 mg (n=60) 300 mg (n=60) 500 mg (n=60) 100 mg (n=59) 200 mg (n=60) 300 mg (n=59) Lp(a) ∼ % change LDL-C 0.22 0.26 0.22 0.29 0.47 0.51 0.35 Lp(a) ∼ absolute change LDL-C 0.35 0.12 0.04 0.22 0.45 0.24 0.27 Lp(a) ∼ % change LDL-C - Statin users 0.16 0.28 0.28 0.31 0.45 0.55 0.37 Lp(a) ∼ % change LDL-C - Non statin users 0.80 -0.08 0.09 0.10 0.63 0.09 0.21 Conclusion The dose-dependent correlation between % changes in LDL-C and Lp(a) suggests that the LDLR may be partially responsible for Lp(a) reductions produced by inclisiran. The numerically stronger correlation in statin-users supports the idea that LDL-C may compete with Lp(a) for LDLR binding especially at low LDL-C levels. Acknowledgement/Funding The Medicines Company

Background: The ORION-1 trial (Trial to Evaluate the Effect of ALN-PCSSC Treatment on Low Density Lipoprotein Cholesterol [LDL-C]) demonstrated that inclisiran, an siRNA therapeutic that targets protease proprotein convertase subtilisin/kexin type 9 mRNA within hepatocytes, produces significant low-density lipoprotein cholesterol reduction. The effects of inclisiran on other lipids are less well described. Methods: ORION-1 was a phase 2 trial assessing 6 different inclisiran dosing regimens versus placebo. Participants with elevated low-density lipoprotein cholesterol despite receiving maximally tolerated statin therapy received a single-dose (200, 300, or 500 mg) or 2-dose starting regimen (100, 200, or 300 mg on days 1 and 90) of inclisiran or placebo. This prespecified analysis reports the percentage reductions in non–high-density lipoprotein cholesterol (non–HDL-C), apolipoprotein (apo) B, very-low-density lipoprotein cholesterol, lipoprotein(a), triglycerides, HDL-C, and apo A1 at the primary efficacy time point (day 180) with mixed-effect models for repeated measures. Additional prespecified analyses report time course of changes from baseline at each visit to day 210, interindividual variation in response, and lipid goal attainment. Results: The mean age of the 501 participants was 63 years, 65% were male, 69% had atherosclerotic cardiovascular disease, 73% used statins, and mean low-density lipoprotein cholesterol was 128 mg/dL. A single dose of inclisiran reduced apo B, non–HDL-C, and very-low-density lipoprotein cholesterol over 210 days. A second dose of inclisiran provided additional lowering of these lipids. At day 180, non–HDL-C was lowered dose-dependently: by 25% from 148±43 to 110±45 mg/dL in the 200-mg single-dose group and by 46% from 161±58 to 91±58 mg/dL in the 2-dose 300-mg group. For the same dosing regimens, apo B was reduced by 23% from 101±23 to 78±29 mg/dL and by 41% from 106±31 to 65±33 mg/dL ( P <0.001 for all groups versus placebo). In the 300-mg 2-dose group, all individuals experienced apo B and non–HDL-C reductions. There was larger interindividual variation in very-low-density lipoprotein cholesterol, triglycerides, and lipoprotein(a) reductions. In the 300-mg 2-dose group, the percentages of patients achieving guideline-recommended apo B goals for high- and very-high-risk patients at day 180 were 78% and 90%; 68% and 83% of participants achieved non–HDL-C <100 and <130 mg/dL. Conclusions: Inclisiran produces significant and prolonged reductions in atherogenic lipoproteins, suggesting that inhibiting the synthesis of protease proprotein convertase subtilisin/kexin type 9 through siRNA may be a viable alternative to other approaches that target protease proprotein convertase subtilisin/kexin type 9. Clinical Trial Registration: URL: https://www.clinicaltrials.gov . Unique identifier: NCT02597127.