Ixekizumab

Class: Skin and Mucous Membrane Agents, Miscellaneous
Chemical Name: Disulfide with human monoclonal LY2439821 κ-chain anti-(human interleukin 17A) (human monoclonal LY2439821 γ4-chain) immunoglobulin G4 dimer
Molecular Formula: C₆₄₉₂H₁₀₀₁₂N₁₇₂₈O₂₀₂₈S₄₆
CAS Number: 1143503-69-8
Brands: Taltz

Introduction

Inhibitor of interleukin-17A (IL-17A), a proinflammatory cytokine; a recombinant humanized IgG₄ kappa monoclonal antibody specific for IL-17A.^{1 14 15}

Uses for Ixekizumab

Plaque Psoriasis

Management of moderate to severe plaque psoriasis in patients who are candidates for phototherapy or systemic therapy.^{1 3 14}

Ixekizumab Dosage and Administration

General

• Evaluate patients for tuberculosis infection prior to initiating ixekizumab.¹

Administration

Sub-Q Administration

Administer by sub-Q injection into the upper arms, thighs, or any quadrant of the abdomen; do not make abdominal injections within 1 inch of the navel.^{1 4 5} Administration into upper arm should be performed by a caregiver or clinician.^{1 4 5}

Rotate injection sites.^{1 4 5}

Do not make injections into areas where the skin is tender, bruised, erythematous, indurated, or affected by psoriasis.^{1 4 5}

Intended for use under the guidance and supervision of a clinician, but may be self-administered if clinician determines the patient and/or caregiver is competent to safely administer the drug after appropriate training.¹

Administration into the thigh resulted in higher bioavailability compared with other injection sites, including the arm and abdomen.¹

Use of Prefilled Autoinjector or Prefilled Syringe

Remove prefilled autoinjector or prefilled syringe from refrigerator and allow to sit at room temperature for 30 minutes prior to injection.^{1 4 5} Do not warm solution by placing in microwave, running hot water over the autoinjector or syringe, or exposing the injection to direct sunlight.^{4 5} Do not remove the base cap of the autoinjector or the needle cap of the syringe while the autoinjector or prefilled syringe is warming to room temperature.^{4 5}

Inject entire contents of the autoinjector or prefilled syringe (1 mL providing 80 mg).¹

Do not shake the solution.^{1 4 5}

Discard any unused portions of solution.¹

Dosage

Adults

Plaque Psoriasis

Sub-Q

160 mg (two 80-mg injections) at week 0 and then 80 mg at weeks 2, 4, 6, 8, 10, and 12, followed by 80 mg every 4 weeks thereafter.¹

Special Populations

Hepatic Impairment

Manufacturer makes no specific dosage recommendations.¹

Renal Impairment

Manufacturer makes no specific dosage recommendations.¹

Geriatric Patients

Manufacturer makes no specific dosage recommendations.¹

Cautions for Ixekizumab

Contraindications

• Known hypersensitivity to the drug or any ingredient in the formulation.¹

Warnings/Precautions

Sensitivity Reactions

Hypersensitivity

Serious hypersensitivity reactions (e.g., angioedema, urticaria) reported.¹ If a serious hypersensitivity reaction occurs, discontinue immediately and initiate appropriate supportive treatment.¹

Infectious Complications

Increased risk of infections.¹ Higher rates of infections (e.g., upper respiratory tract infections, oral candidiasis, conjunctivitis, tinea infections) observed in psoriasis patients receiving ixekizumab compared with those receiving placebo.¹

Neutropenia, generally grade 1 or 2, reported; however, not associated with increased rate of infection in clinical studies.¹

If a serious infection develops or if an infection fails to respond to standard therapy, monitor patient closely and discontinue ixekizumab until the infection resolves.¹

Evaluate patients for tuberculosis before initiating ixekizumab.¹ Do not administer to patients with active tuberculosis infection.¹ When indicated, initiate appropriate antimycobacterial regimen for treatment of latent tuberculosis infection before initiating ixekizumab.¹ Also consider antimycobacterial therapy for patients with a history of latent or active tuberculosis in whom an adequate course of antimycobacterial treatment cannot be confirmed.¹ Closely monitor patients for active tuberculosis during and after ixekizumab treatment.¹

Inflammatory Bowel Disease

Crohn’s disease and ulcerative colitis, including exacerbations, reported more frequently in patients receiving ixekizumab compared with those receiving placebo.¹ Monitor for onset or exacerbation of inflammatory bowel disease.¹

Immunization

Consider administering all age-appropriate vaccines recommended by current immunization guidelines before initiating ixekizumab.¹

Avoid live vaccines during therapy.¹ (See Vaccines under Interactions.)

Immunogenicity

Antibodies to ixekizumab, including neutralizing antibodies, reported.¹ Associated with decreased drug concentrations and decreased clinical response or loss of efficacy.¹

Specific Populations

Pregnancy

Data regarding use and associated risks in pregnant women not available.¹ Potential for fetal exposure since human IgG crosses the placenta and ixekizumab crossed the placenta in monkeys.¹

In studies in cynomolgus monkeys, no evidence of adverse embryofetal developmental effects; however, increased neonatal deaths observed when administration continued until parturition.¹ No adverse effects on functional or immunologic development observed from birth through 6 months of age.¹

Lactation

Not known whether ixekizumab distributes into human milk, affects human milk production, or affects breast-fed infant.¹ Ixekizumab distributes into milk in cynomolgus monkeys.¹

Consider benefits of breast-feeding and importance of the drug to the woman; also consider any potential adverse effects on the breast-fed infant from the drug or underlying maternal condition.¹

Pediatric Use

Safety and efficacy not established in pediatric patients <18 years of age.¹

Geriatric Use

No apparent differences in safety or efficacy between geriatric patients and younger adults with psoriasis; however, insufficient experience in patients ≥65 years of age to determine whether they respond differently than younger adults.¹

Hepatic Impairment

No formal studies to date.¹

Renal Impairment

No formal studies to date.¹

Common Adverse Effects

Injection site reactions,^{1 3 14} upper respiratory tract infections (e.g., nasopharyngitis, rhinovirus infection),^{1 3 14} nausea,¹ tinea infections.¹

Interactions for Ixekizumab

No formal drug interaction studies to date.¹

Drugs Metabolized by Hepatic Microsomal Enzymes

Because elevated levels of certain cytokines during chronic inflammation may alter formation of CYP isoenzymes, antagonism of IL-17A activity by ixekizumab could normalize formation of CYP enzymes.¹

CYP substrates: Upon initiation or discontinuance of ixekizumab, consider monitoring for therapeutic effect or drug concentration and consider dosage adjustment of the CYP substrate, especially if substrate has a narrow therapeutic index.¹

Vaccines

Avoid live vaccines.¹ No data available regarding response to live or inactivated vaccines in patients receiving ixekizumab.¹

Specific Drugs

Ixekizumab Pharmacokinetics

Absorption

Bioavailability

Bioavailability is 60–81% following sub-Q administration.¹ Higher bioavailability attained when administered into thigh compared with other injection sites, including arm and abdomen.¹

Peak plasma concentrations achieved by approximately 4 days after a single 160-mg sub-Q dose.¹

Steady-state concentrations attained by week 8 in patients receiving initial 160-mg dose followed by 80 mg every 2 weeks.¹ After dosage changed at week 12 to 80 mg every 4 weeks, new steady state achieved in approximately 10 weeks.¹

Pharmacokinetics are dose proportional over a sub-Q dose range of 5–160 mg.¹

Distribution

Extent

Not known whether distributed into human milk.¹

Special Populations

Volume of distribution increases as body weight increases.¹

Elimination

Metabolism

Metabolic pathway not characterized.¹

Expected to be degraded into small peptides and amino acids via catabolic pathways in the same manner as endogenous IgG.¹

Half-life

13 days.¹

Special Populations

Pharmacokinetics not formally studied in renal or hepatic impairment.¹

Age does not substantially alter clearance in adults with plaque psoriasis.¹

Clearance increases as body weight increases.¹

Stability

Storage

Parenteral

Injection

Autoinjector or prefilled syringe: 2–8°C.¹ Keep in original carton and protect from light.¹ Do not freeze.¹

Actions

• Binds to IL-17A and inhibits interaction with the IL-17 receptor.^{1 11}

• Elevated levels of IL-17A found in psoriatic lesions and blood of individuals with psoriasis.^{7 8 9 10}

• Neutralizes biologic activity of IL-17A and inhibits release of proinflammatory cytokines and chemokines.^{1 11}

Advice to Patients

• Provide all patients with a copy of the manufacturer's patient information (medication guide) and instructions for use for ixekizumab with each prescription of the drug.¹ Importance of patients reading the medication guide and instructions for use prior to initiation of therapy and each time the prescription is refilled.¹

• Importance of instructing patient and/or caregiver regarding proper storage, dosage, and administration of ixekizumab, including the use of aseptic technique, as well as proper disposal of needles and syringes if it is determined that the patient and/or caregiver is competent to safely administer the drug.¹

• If a dose of ixekizumab is missed, importance of administering the missed dose as soon as possible and then resuming the regular dosing schedule.¹

• Increased susceptibility to infection.¹ Importance of promptly informing clinician if any signs or symptoms of infection (e.g., fever, sweats, or chills; muscle aches; cough, shortness of breath, or blood in the phlegm; weight loss; warm, red, or painful sores on the body; diarrhea or stomach pain; burning upon urination or increased urination) occur.¹

• Importance of informing clinician if new or worsening symptoms of inflammatory bowel disease (e.g., abdominal pain, diarrhea, weight loss) occur.¹

• Importance of reviewing vaccination status with clinician and receiving all appropriate vaccines prior to initiation of ixekizumab.¹

• Importance of seeking immediate medical attention if symptoms of a serious allergic reaction (e.g., feeling of faintness; swelling of eyelids, face, lips, mouth, tongue, or throat; dyspnea or throat tightness; chest tightness; rash) occur.¹

• Importance of informing clinicians of existing or contemplated concomitant therapy, including prescription and OTC drugs, as well as any concomitant illnesses (e.g., active infection, inflammatory bowel disease) or any history of tuberculosis or other infections.¹

• Importance of women informing clinicians if they are or plan to become pregnant or plan to breast-feed.¹

• Importance of informing patients of other important precautionary information.¹ (See Cautions.)

Preparations

Excipients in commercially available drug preparations may have clinically important effects in some individuals; consult specific product labeling for details.

Please refer to the ASHP Drug Shortages Resource Center for information on shortages of one or more of these preparations.