Pharmacological properties : תכונות פרמקולוגיות

Pharmacodynamic Properties

5.1   Pharmacodynamic properties

Pharmacotherapeutic group: lipid modifying agents, other lipid modifying agents, ATC code: C10AX16

Mechanism of action

Inclisiran is a cholesterol-lowering, double-stranded, small interfering ribonucleic acid (siRNA), conjugated on the sense strand with triantennary N-acetylgalactosamine (GalNAc) to facilitate uptake by hepatocytes. In hepatocytes, inclisiran utilises the RNA interference mechanism and directs catalytic breakdown of mRNA for proprotein convertase subtilisin kexin type 9. This increases LDL-C receptor recycling and expression on the hepatocyte cell surface, which increases LDL-C uptake and lowers LDL-C levels in the circulation.

LEQ API OCT22 V2                                                                  EU SmPC 08.2022 Pharmacodynamic effects

Following a single subcutaneous administration of 284 mg inclisiran, LDL-C reduction was apparent within 14 days post-dose. Mean reductions of 49-51% for LDL-C were observed 30 to 60 days post-dose. At day 180, LDL-C levels were still reduced by approximately 53%.

Clinical efficacy and safety

In clinical studies and some publications, the 284 mg inclisiran dose is equivalent and referred to as 300 mg inclisiran sodium salt.

The efficacy of inclisiran was evaluated in three phase III studies in patients with atherosclerotic cardiovascular disease (ASCVD) (coronary heart disease, cerebrovascular disease or peripheral artery disease), ASCVD risk equivalents (type 2 diabetes mellitus, familial hypercholesterolaemia, or 10-year risk of 20% or greater of having a cardiovascular event assessed by Framingham Risk Score or equivalent) and/or familial hypercholesterolaemia (FH). Patients were taking a maximally tolerated dose of statin with or without other lipid-modifying therapy and required additional LDL-C reduction (patients unable to reach their treatment goals). Approximately 17% of patients were statin intolerant.
Patients were administered subcutaneous injections of 284 mg inclisiran or placebo on day 1, day 90, day 270 and day 450. Patients were followed until day 540.

The effect of inclisiran on cardiovascular morbidity and mortality has not yet been determined.

In the phase III pooled analysis, subcutaneously administered inclisiran lowered LDL-C between 50% and 55% as early as day 90 (Figure 1), which was maintained during long-term therapy. Maximal LDL-C reduction was achieved at day 150 following a second administration. Small but statistically significant increased LDL-C reductions up to 65% were associated with lower baseline LDL-C levels (approximately <2 mmol/l [77 mg/dl]), higher baseline PCSK9 levels and higher statin doses and statin intensity.

Figure 1                                        Mean percentage change from baseline LDL-C in patients with primary hypercholesterolaemia and mixed dyslipidaemia treated with inclisiran compared to placebo (pooled analysis)
Mean percentage change from baseline



Inclisiran                   Placebo



No. of patients
Placebo
Inclisiran


ASCVD and ASCVD risk equivalents
Two studies were conducted in patients with ASCVD and ASCVD risk equivalents (ORION-10 and ORION-11). Patients were taking a maximally tolerated dose of statins with or without other lipid-modifying therapy, such as ezetimibe, and required additional LDL-C reduction. As lowering LDL-C is expected to improve cardiovascular outcomes, the co-primary endpoints in each study were the percentage change in LDL-C from baseline to day 510 relative to placebo and the time-adjusted LEQ API OCT22 V2                                                                                            EU SmPC 08.2022 percentage change in LDL-C from baseline after day 90 and up to day 540 to estimate the integrated effect on LDL-C over time.

ORION-10 was a multicentre, double-blind, randomised, placebo-controlled 18-month study conducted in 1,561 patients with ASCVD.

The mean age at baseline was 66 years (range: 35 to 90 years), 60% were ≥65 years old, 31% were women, 86% were White, 13% were Black, 1% were Asian and 14% were Hispanic or Latino ethnicity. The mean baseline LDL C was 2.7 mmol/l (105 mg/dl). Sixty-nine percent (69%) were taking high-intensity statins, 19% were taking medium-intensity statins, 1% were taking low-intensity statins and 11% were not on a statin. The most commonly administered statins were atorvastatin and rosuvastatin.

Inclisiran significantly reduced the mean percentage change in LDL-C from baseline to day 510 compared to placebo by 52% (95% CI: -56%, -49%; p <0.0001) (Table 2).

Inclisiran also significantly reduced the time-adjusted percentage change in LDL-C from baseline after day 90 and up to day 540 by 54% compared to placebo (95% CI: -56%, -51%; p <0.0001). For additional results, see Table 2.

Table 2       Mean percentage change from baseline and difference from placebo in lipid parameters at day 510 in ORION-10

Treatment group           LDL-C            Total        Non-HDL-C        Apo-B           Lp(a)* cholesterol
Mean baseline            105                181             134            94              122 value in mg/dl**
Day 510 (mean percentage change from baseline)
Placebo (n=780)           1              0                   0              -2              4 Inclisiran (n=781)       -51            -34                 -47            -45             -22 Difference from          -52            -33                 -47            -43             -26 placebo (LS mean)     (-56, -49)     (-35, -31)          (-50, -44)     (-46, -41)      (-29, -22) (95% CI)
*At day 540; median percentage change in Lp(a) values
**Mean baseline value in nmol/l for Lp(a)

At day 510, the LDL-C target of <1.8 mmol/l (70 mg/dl) was achieved by 84% of inclisiran patients with ASCVD compared to 18% of placebo patients.

Consistent and statistically significant (p<0.0001) reductions in percentage change in LDL-C from baseline to day 510 and time-adjusted percentage change in LDL-C from baseline after day 90 and up to day 540 were observed across all subgroups irrespective of baseline demographics, baseline disease characteristics (including gender, age, body mass index, race and baseline statin use), comorbidities and geographic regions.

ORION-11 was an international, multicentre, double-blind, randomised, placebo-controlled 18-month study which evaluated 1,617 patients with ASCVD or ASCVD risk equivalents. More than 75% of patients were receiving a high-intensity statin background treatment, 87% of patients had ASCVD and 13% were ASCVD risk equivalent.

The mean age at baseline was 65 years (range: 20 to 88 years), 55% were ≥65 years old, 28% were women, 98% were White, 1% were Black ,1% were Asian and 1% were Hispanic or Latino ethnicity.
The mean baseline LDL-C was 2.7 mmol/l (105 mg/dl). Seventy-eight percent (78%) were taking high-intensity statins, 16% were taking medium-intensity statins, 0.4% were taking low-intensity statins and 5% were not on a statin. The most commonly administered statins were atorvastatin and rosuvastatin.
LEQ API OCT22 V2                                                               EU SmPC 08.2022 Inclisiran significantly reduced the mean percentage change in LDL-C from baseline to day 510 compared to placebo by 50% (95% CI: -53%, -47%; p<0.0001) (Table 3).

Inclisiran also significantly reduced time-adjusted percentage change in LDL-C from baseline after day 90 and up to day 540 by 49% compared to placebo (95% CI: -52%, -47%; p<0.0001). For additional results, see Table 3.

Table 3      Mean percentage change from baseline and difference from placebo in lipid parameters at day 510 in ORION-11

Treatment group           LDL-C            Total         Non-HDL-C           Apo-B           Lp(a)* cholesterol
Mean baseline            105                185               136              96              107 value in mg/dl**
Day 510 (mean percentage change from baseline)
Placebo (n=807)           4              2                     2               1                0 Inclisiran (n=810)       -46            -28                   -41             -38              -19 Difference from          -50            -30                   -43             -39              -19 placebo (LS mean)     (-53, -47)     (-32, -28)            (-46, -41)      (-41, -37)       (-21, -16) (95% CI)
*At day 540; median percentage change in Lp(a) values
**Mean baseline value in nmol/l for Lp(a)

At day 510, the LDL-C target of <1.8 mmol/l (70 mg/dl) was achieved by 82% of inclisiran patients with ASCVD compared to 16% of placebo patients. In patients with an ASCVD risk equivalent, the LDL-C target of <2.6 mmol/l (100 mg/dl) was achieved by 78% of inclisiran patients compared to 31% of placebo patients.

Consistent and statistically significant (p<0.05) percentage change in LDL-C from baseline to day 510 and time-adjusted percentage change in LDL-C from baseline after day 90 and up to day 540 was observed across all subgroups irrespective of baseline demographics, baseline disease characteristics (including gender, age, body mass index, race and baseline statin use), comorbidities, and geographic regions.

Heterozygous familial hypercholesterolaemia
ORION-9 was an international, multicentre, double-blind, randomised, placebo-controlled 18-month trial in 482 patients with heterozygous familial hypercholesterolaemia (HeFH). All patients were taking maximally tolerated doses of statins with or without other lipid-modifying therapy, such as ezetimibe, and required additional LDL-C reduction. The diagnosis of HeFH was made either by genotyping or clinical criteria (“definite FH” using either the Simon Broome or WHO/Dutch Lipid Network criteria).

The co-primary endpoints were the percentage change in LDL-C from baseline to day 510 relative to placebo, and the time-adjusted percentage change in LDL-C from baseline after day 90 and up to day 540 to estimate the integrated effect on LDL-C over time. Key secondary endpoints were the absolute change in LDL-C from baseline to day 510, the time-adjusted absolute change in LDL-C from baseline after day 90 and up to day 540 and the percentage change from baseline to day 510 in PCSK9, total cholesterol, Apo-B, and non-HDL-C. Additional secondary endpoints included the, individual responsiveness to inclisiran and the proportion of patients attaining global lipid targets for their level of ASCVD risk.

The mean age at baseline was 55 years (range: 21 to 80 years), 22% were ≥65 years old, 53% were women, 94% were White, 3% were Black, 3% were Asian and 3% were Hispanic or Latino ethnicity.
The mean baseline LDL-C was 4.0 mmol/l (153 mg/dl). Seventy-four percent (74%) were taking high-intensity statins, 15% were taking medium-intensity statins and 10% were not on a statin.
LEQ API OCT22 V2                                                                  EU SmPC 08.2022 Fifty-two percent (52%) of patients were treated with ezetimibe. The most commonly administered statins were atorvastatin and rosuvastatin.

Inclisiran significantly reduced the mean percentage change in LDL-C from baseline to day 510 compared to placebo by 48% (95% CI: -54%, -42%; p<0.0001) (Table 4).

Inclisiran also significantly reduced the time-adjusted percentage change in LDL-C from baseline after day 90 and up to day 540 by 44% compared to placebo (95% CI: -48%, -40%; p<0.0001). For additional results, see Table 4.

Table 4        Mean percentage change from baseline and difference from placebo in lipid parameters at day 510 in ORION-9

Treatment group           LDL-C            Total        Non-HDL-C         Apo-B            Lp(a)* cholesterol
Mean baseline            153                231             180             124             121 value in mg/dl**
Day 510 (mean percentage change from baseline)
Placebo (n=240)           8              7                   7               3               4 Inclisiran (n=242)       -40            -25                 -35             -33             -13 Difference from          -48            -32                 -42             -36             -17 placebo (LS mean)                                                                        (-22, -12) (-54, -42)     (-36, -28)          (-47, -37)      (-40, -32)
(95% CI)
*At day 540; median percentage change in Lp(a) values
**Mean baseline value in nmol/l for Lp(a)

At day 510, 52.5% of inclisiran patients with ASCVD achieved their LDL-C target of <1.8 mmol/l (70 mg/dl) compared to 1.4% of placebo patients with ASCVD, while in the group with ASCVD risk equivalents 66.9% of inclisiran patients achieved their LDL-C target of <2.6 mmol/l (100 mg/dl) compared to 8.9% of placebo patients.

Consistent and statistically significant (p<0.05) percentage change in LDL-C from baseline to day 510 and time-adjusted percentage change in LDL-C from baseline after day 90 and up to day 540 were observed across all subgroups irrespective of baseline demographics, baseline disease characteristics (including gender, age, body mass index, race and baseline statin use), comorbidities, and geographic regions.

Pharmacokinetic Properties

5.2   Pharmacokinetic properties

Absorption

Following single subcutaneous administration, systemic exposure to inclisiran increased approximately dose-proportionally over a range from 24 mg to 756 mg. At the recommended dosing regimen of 284 mg plasma concentrations reached peak in approximately 4 hours post dose, with a mean Cmax of 509 ng/ml. Concentrations reached undetectable levels within 48 hours post dosing. The mean area under the plasma concentration-time curve from dosing extrapolated to infinity was 7980 ng*h/ml. Pharmacokinetic findings following multiple subcutaneous administrations of inclisiran were similar to single-dose administration.

Distribution

Inclisiran is 87% protein bound in vitro at the relevant clinical plasma concentrations. Following a single subcutaneous 284 mg dose of inclisiran to healthy adults, the apparent volume of distribution is 

LEQ API OCT22 V2                                                                EU SmPC 08.2022 approximately 500 litres. Based on non-clinical data inclisiran has been shown to have high uptake into and selectivity for the liver, the target organ for cholesterol lowering.

Biotransformation

Inclisiran is primarily metabolised by nucleases to shorter inactive nucleotides of varying length.
Inclisiran is not a substrate for common drug transporters and, although in vitro studies were not conducted, it is not anticipated to be a substrate for cytochrome P450.

Elimination

The terminal elimination half-life of inclisiran is approximately 9 hours and no accumulation occurs with multiple dosing. Sixteen percent (16%) of inclisiran is cleared through the kidney.

Linearity/non-linearity

In the phase I clinical study, an approximately dose proportional increase in inclisiran exposure was observed after administration of subcutaneous doses of inclisiran ranging from 24 mg to 756 mg. No accumulation and no time-dependent changes were observed after multiple subcutaneous doses of inclisiran.

Pharmacokinetic/pharmacodynamic relationship(s)

In the phase I clinical study, a dissociation was observed between inclisiran pharmacokinetic parameters and LDL-C pharmacodynamic effects. Selective delivery of inclisiran to hepatocytes, where it is incorporated into the RNA-induced silencing complex (RISC), results in a long duration of action, beyond that anticipated based on the plasma elimination half-life of 9 hours. The maximal effects of reducing LDL-C were observed with a 284 mg dose, with higher doses not producing greater effects.

Special populations

Renal impairment
Pharmacokinetic analysis of data from a dedicated renal impairment study reported an increase in inclisiran Cmax of approximately 2.3, 2.0 and 3.3-fold and an increase in inclisiran AUC of approximately 1.6, 1.8 and 2.3-fold, in patients with mild (creatinine clearance [CrCL] of 60 ml/min to 89 ml/min), moderate (CrCL of 30 ml/min to 59 ml/min) and severe (CrCL of 15 ml/min to 29 ml/min) renal impairment, respectively, relative to patients with normal renal function. Despite the higher transient plasma exposures over 48 hours, the reduction in LDL-C was similar across all groups of renal function. Based on population pharmacodynamic modelling, no dose adjustment is recommended in patients with end-stage renal disease. Based on pharmacokinetic, pharmacodynamic and safety assessments, no dose adjustment is necessary in patients with mild, moderate or severe renal impairment. The effect of haemodialysis on inclisiran pharmacokinetics has not been studied.
Considering that inclisiran is eliminated renally, haemodialysis should not be performed for at least 72 hours after Leqvio dosing.

Hepatic impairment
Pharmacokinetic analysis of data from a dedicated hepatic impairment study reported an increase in inclisiran Cmax of approximately 1.1 and 2.1-fold, and an increase in inclisiran AUC of approximately1.3 and 2.0-fold, respectively, in patients with mild (Child-Pugh class A) and moderate (Child-Pugh class B) hepatic impairment relative to patients with normal hepatic function. Despite the higher transient inclisiran plasma exposures, the reductions in LDL-C were similar between the groups of patients administered inclisiran with normal hepatic function and mild hepatic impairment. In patients with moderate hepatic impairment baseline PCSK9 levels were markedly lower and the reduction in LDL-C was less than that observed in patients with normal hepatic function. No dose adjustment is necessary in patients with mild to moderate hepatic impairment (Child-Pugh class A and B). Leqvio has not been studied in patients with severe hepatic impairment (Child-Pugh class C).
LEQ API OCT22 V2                                                                 EU SmPC 08.2022 Other special populations
A population pharmacodynamic analysis was conducted on data from 4,328 patients. Age, body weight, gender, race, and creatinine clearance were not found to significantly influence inclisiran pharmacodynamics. No dose adjustments are recommended for patients with these demographics.