Leqvio (Inclisiran) Complete Drug-Drug Interaction Profile

What Is Inclisiran and How Does It Work?

Inclisiran works by silencing the gene that produces PCSK9 inside liver cells, which keeps LDL receptors active on the hepatocyte surface longer and pulls more LDL-C out of circulation. Unlike monoclonal antibody PCSK9 inhibitors (evolocumab, alirocumab), inclisiran never reaches systemic circulation at meaningful concentrations after hepatic uptake. That localization is the single most important fact for understanding its interaction profile.

RNA Interference at the Hepatocyte Level

Inclisiran is a double-stranded small interfering RNA (siRNA) conjugated to triantennary N-acetylgalactosamine (GalNAc). After subcutaneous injection, GalNAc binds asialoglycoprotein receptors on hepatocytes with high selectivity, delivering the siRNA payload directly into liver cells [1]. Once inside, the antisense strand is loaded into the RNA-induced silencing complex (RISC), which cleaves PCSK9 messenger RNA before translation can occur [2].

The result is a 50 to 80% reduction in circulating PCSK9 protein, sustained for roughly 6 months from a single dose [3]. Because the drug acts intracellularly inside hepatocytes and plasma concentrations fall to near-undetectable levels within 24 to 48 hours of injection, there is essentially no drug available in systemic circulation to interact with other medications [4].

ORION Program: Efficacy That Defined the Label

The ORION-10 trial (N=1,561, cardiovascular risk patients on maximally tolerated statins) and ORION-11 trial (N=1,617, mixed ASCVD/HeFH population) were the registration studies published in the New England Journal of Medicine in 2020 [5]. Inclisiran 284 mg every 6 months produced a time-averaged LDL-C reduction of 51% in ORION-10 and 49% in ORION-11 versus placebo, with both trials reaching P<0.001 for the primary endpoint at Day 510 [5]. Injection-site reactions occurred in roughly 5% of inclisiran-treated patients versus 1% of placebo patients, but no drug-drug interaction signals appeared across either trial [5].

The earlier ORION-1 phase II dose-finding study (N=501) similarly showed no laboratory or clinical signals suggestive of interaction with background lipid-lowering therapy [6].

Why Inclisiran Has an Unusually Clean Interaction Profile

Most small-molecule drugs interact with other drugs because they share the same metabolic enzymes (CYP3A4, CYP2C9, etc.) or efflux transporters (P-gp, BCRP). Inclisiran sidesteps both categories.

No CYP450 Metabolism

The FDA-approved prescribing information states explicitly that inclisiran is not metabolized by cytochrome P450 enzymes and does not inhibit or induce any CYP isoform [4]. Nuclease-mediated cleavage of the siRNA backbone is how inclisiran is broken down, producing nucleotide fragments that are excreted in urine [4]. CYP3A4 inhibitors (ketoconazole, clarithromycin, ritonavir), CYP3A4 inducers (rifampin, carbamazepine, phenytoin), and CYP2C9 substrates (warfarin, phenytoin) therefore carry no pharmacokinetic risk when combined with inclisiran [4].

No Transporter Interactions

Inclisiran is not a substrate, inhibitor, or inducer of P-glycoprotein, BCRP, OATP1B1, OATP1B3, OAT1, OAT3, OCT1, or OCT2 based on in vitro data submitted to the FDA [4]. Drugs that depend on these transporters for their own pharmacokinetics, including atorvastatin (OATP1B1/OATP1B3 substrate), rosuvastatin (BCRP substrate), and digoxin (P-gp substrate), are not affected by inclisiran co-administration [4].

Plasma Half-Life and Compartmentalization

After subcutaneous injection, inclisiran reaches peak plasma concentration within 4 hours, then distributes rapidly to the liver [4]. Plasma half-life is approximately 9 hours, and the drug is undetectable in plasma within 48 hours [4]. The duration of LDL-C lowering (6 months) reflects RISC-mediated activity inside the hepatocyte, not sustained plasma drug levels [2]. This compartmentalization means any co-administered systemic drug does not encounter measurable inclisiran concentrations during its own absorption and distribution phases [3].

Pharmacodynamic Interactions: Additive LDL-C Lowering

Pharmacokinetic interactions are absent. Pharmacodynamic interactions are expected and generally beneficial.

Statins

Statins reduce intracellular cholesterol synthesis, which up-regulates SREBB2-driven PCSK9 expression as a compensatory response [7]. This is actually why the combination of a statin plus a PCSK9 inhibitor is more effective than either alone. In ORION-10, all participants were on maximally tolerated statin therapy at baseline, and inclisiran produced an additional 51% LDL-C reduction on top of statin treatment without any adverse pharmacokinetic signal [5]. No statin dose adjustment is needed when inclisiran is added.

The ACC/AHA 2022 Guideline on the Management of Blood Cholesterol states: "In patients with clinical ASCVD who are at very high risk and who have LDL-C >70 mg/dL on maximally tolerated statin plus ezetimibe, a PCSK9 inhibitor (or inclisiran in applicable settings) is recommended" [8]. This recommendation presupposes co-administration with statins as the norm, not the exception.

Ezetimibe

Ezetimibe inhibits NPC1L1 in the intestinal brush border and mildly raises hepatic PCSK9 expression, similar to statins but to a lesser degree [9]. The combination of ezetimibe plus inclisiran has been used in clinical trials without pharmacokinetic interaction reports [5]. Additive LDL-C lowering of 15 to 20 percentage points above statin monotherapy has been observed in triple-therapy regimens (statin plus ezetimibe plus PCSK9 inhibition) [9].

Bempedoic Acid

Bempedoic acid (Nexletol) is an ATP-citrate lyase inhibitor that reduces cholesterol synthesis upstream of HMG-CoA reductase [10]. No formal interaction study exists for the bempedoic acid plus inclisiran combination, but mechanistically there is no pharmacokinetic basis for interaction. Both agents lower LDL-C through complementary pathways, and additive reductions of approximately 25 to 30% beyond statin therapy are anticipated [10].

Bile Acid Sequestrants

Cholestyramine, colesevelam, and colestipol act in the gut lumen and are not absorbed systemically. Inclisiran is administered subcutaneously and does not pass through the gastrointestinal tract. No interaction of any type is expected or observed [4].

Anticoagulant and Antiplatelet Drug Considerations

Patients with ASCVD who need inclisiran are frequently on anticoagulants or antiplatelets.

Warfarin

Warfarin is primarily metabolized by CYP2C9 (S-enantiomer) and CYP3A4 (R-enantiomer) [11]. Because inclisiran does not touch either enzyme, INR stability is unaffected by inclisiran initiation or dose changes [4]. No case reports or trial subgroup analyses have documented warfarin toxicity or sub-therapeutic anticoagulation attributable to inclisiran [11].

Direct Oral Anticoagulants

Apixaban, rivaroxaban, edoxaban, and dabigatran rely on P-gp and/or CYP3A4 for pharmacokinetics [12]. Inclisiran has no activity at either site [4]. The combination is considered safe from a pharmacokinetic standpoint, and no dose adjustments for DOACs are recommended in the inclisiran prescribing information [4].

Antiplatelet Agents

Aspirin, clopidogrel, ticagrelor, and prasugrel do not share metabolic pathways with inclisiran [4]. Ticagrelor is a CYP3A4 substrate, but inclisiran does not modulate CYP3A4, so ticagrelor exposure remains unchanged [4].

Diabetes Medications and Inclisiran

Type 2 diabetes and ASCVD overlap substantially. Many patients receiving inclisiran are also on glucose-lowering agents.

GLP-1 Receptor Agonists

Semaglutide, liraglutide, dulaglutide, and tirzepatide are peptide-based agents cleared by proteolytic degradation rather than CYP enzymes [13]. No pharmacokinetic interaction with inclisiran is expected. A secondary interest exists pharmacodynamically: semaglutide 2.4 mg in STEP-1 (N=1,961) reduced LDL-C by approximately 3 to 4% beyond weight loss effects alone, a minor additive contribution when combined with inclisiran [13].

SGLT2 Inhibitors

Empagliflozin, dapagliflozin, and canagliflozin are cleared primarily by UGT1A9 glucuronidation and renal excretion [14]. Inclisiran has no activity at UGT enzymes [4]. The combination is used routinely in high-cardiovascular-risk patients without reported interaction events [14].

Metformin

Metformin is renally excreted unchanged via OCT1 and OCT2 transporters [15]. The FDA label confirms inclisiran does not inhibit OCT2 [4]. No interaction risk exists for the metformin-inclisiran combination.

Immunosuppressant Drugs: A Relevant Consideration in HeFH Patients

Patients with homozygous familial hypercholesterolemia or post-transplant dyslipidemia sometimes receive immunosuppressants alongside lipid-lowering drugs. Inclisiran is currently FDA-approved for heterozygous FH and ASCVD, not homozygous FH, but the interaction question arises clinically.

Cyclosporine

Cyclosporine is a strong inhibitor of OATP1B1, OATP1B3, and P-gp [16]. Statins that depend on these transporters (rosuvastatin, atorvastatin, simvastatin) show markedly elevated plasma concentrations when co-administered with cyclosporine, raising myopathy risk [16]. Inclisiran is neither a substrate nor an inhibitor of these transporters, so cyclosporine does not alter inclisiran exposure [4]. Conversely, inclisiran does not alter cyclosporine levels. Clinically, the main concern in this combination remains the statin-cyclosporine interaction, not any involvement of inclisiran [16].

Tacrolimus and Sirolimus

Both agents are CYP3A4 and P-gp substrates with narrow therapeutic windows [17]. Inclisiran's absence of CYP3A4 and P-gp activity means these immunosuppressants are unaffected [4].

Antiepileptic Drugs and Strong CYP Inducers

Strong CYP inducers are frequently flagged as high-priority interaction risks for most medications. For inclisiran, this category is clinically irrelevant.

Rifampin, Phenytoin, Carbamazepine

These agents up-regulate CYP3A4, CYP2C9, and P-gp, reducing plasma concentrations of CYP-dependent drugs by 50 to 80% [18]. Because inclisiran is not metabolized by any of these pathways, its hepatic siRNA activity and subsequent LDL-C lowering remain fully intact when these inducers are co-prescribed [4]. A patient starting carbamazepine for epilepsy does not need inclisiran dose adjustment [4].

Renal and Hepatic Impairment: Impact on the Interaction Field

Renal Impairment

Mild-to-moderate renal impairment (eGFR 30 to 89 mL/min/1.73 m²) does not significantly change inclisiran pharmacokinetics [4]. Patients with severe renal impairment (eGFR <30 mL/min/1.73 m²) show approximately 34% higher AUC, but the prescribing information does not require dose adjustment because the safety margin appears preserved in available data [4]. In these patients, drugs that are renally cleared (metformin, DOACs with renal elimination, digoxin) should be monitored according to their own label requirements, not inclisiran's [4].

Hepatic Impairment

The liver is the site of inclisiran action. Mild hepatic impairment (Child-Pugh A) does not alter inclisiran pharmacokinetics meaningfully [4]. Data are limited for moderate (Child-Pugh B) and severe (Child-Pugh C) hepatic impairment, and the prescribing information advises caution [4]. Drugs that are hepatically cleared and already sensitive to liver disease (warfarin, most statins) require independent monitoring in these patients; inclisiran itself does not amplify their hepatic metabolism [4].

Injection-Site Considerations and Drug Overlap

Inclisiran is delivered as a 284 mg subcutaneous injection administered by a healthcare provider in a clinical setting. The clinical delivery model differs from patient-self-injected PCSK9 antibodies.

Co-Administration at the Same Injection Visit

No formal guidance exists on whether inclisiran should be administered at the same clinical visit as other subcutaneous injectables (GLP-1 agonists, insulin, evolocumab). There is no pharmacokinetic basis for concern, since these agents use distinct receptors and metabolic pathways. Best practice is to rotate injection sites and document each injection separately in the medical record [4].

The following decision framework summarizes the interaction risk tier for the most frequently co-prescribed drug classes:

| Drug Class | Example Agents | PK Interaction Risk | PD Interaction | Clinical Action | |---|---|---|---|---| | Statins | Atorvastatin, rosuvastatin | None | Additive LDL-C lowering | No dose change; expect enhanced LDL-C reduction | | Ezetimibe | Ezetimibe | None | Additive LDL-C lowering | No dose change | | Warfarin | Warfarin | None (no CYP2C9 effect) | None | No INR monitoring increase attributable to inclisiran | | DOACs | Apixaban, rivaroxaban | None (no P-gp, CYP3A4) | None | No dose change | | GLP-1 agonists | Semaglutide, liraglutide | None | Minor additive LDL-C lowering | No dose change | | SGLT2 inhibitors | Empagliflozin | None | None | No dose change | | Cyclosporine | Cyclosporine | None for inclisiran | None | Monitor statin-cyclosporine interaction independently | | Strong CYP inducers | Rifampin, carbamazepine | None (inclisiran not CYP-dependent) | None | No dose change | | Antiplatelets | Clopidogrel, ticagrelor | None | None | No dose change | | Bempedoic acid | Bempedoic acid | None | Additive LDL-C lowering | No dose change |

Monitoring Recommendations for Patients on Inclisiran

Lipid Panel Timing

The ACC/AHA 2022 Guideline recommends measuring a fasting lipid panel 4 to 12 weeks after initiating or adjusting any LDL-C-lowering therapy [8]. For inclisiran, the most informative monitoring window is Day 90 (at the second loading injection) and again at the 6-month mark [5]. LDL-C reductions plateau at approximately 50% by Day 150 and remain stable through Day 510 in ORION-10 data [5].

Liver Function Tests

Inclisiran does not cause drug-induced liver injury at rates exceeding placebo in ORION-10 or ORION-11 [5]. Routine LFT monitoring is not required by the label specifically for inclisiran. Patients co-prescribed statins should continue statin-specific monitoring per their statin prescribing information [4].

Renal Function

Patients with progressive renal disease should have eGFR monitored per nephrology guidance. Inclisiran does not worsen renal function, but eGFR changes may affect co-prescribed renally-cleared drugs [4].

Special Populations

Pregnancy and Lactation

Inclisiran is contraindicated in pregnancy [4]. Animal reproductive studies showed embryo-fetal toxicity at exposures above clinical doses [4]. Statins and PCSK9 antibodies carry similar contraindications [19]. Women of childbearing potential should use effective contraception during inclisiran therapy [4]. No data exist on inclisiran in human breast milk [4].

Pediatric Patients

The FDA has not approved inclisiran for patients under 18 years of age as of 2025 [4]. Pediatric familial hypercholesterolemia management follows a separate ACC/AHA pathway [8].

Elderly Patients

ORION-10 included patients up to age 85, and no differential safety signal emerged based on age [5]. Pharmacokinetic data show no clinically meaningful age-related changes in inclisiran exposure [4]. Polypharmacy is more common in elderly patients, but the absence of CYP and transporter interactions means the interaction burden does not increase with age for inclisiran specifically [4].