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Ixekizumab is a humanized anti-interleukin-17 monoclonal antibody that is FDA approved for the treatment of of adults with moderate-to-severe plaque psoriasis who are candidates for systemic therapy or phototherapy. Common adverse reactions include injection site reactions, upper respiratory tract infections, nausea, and tinea infections (≥1%).
Adult Indications and Dosage
FDA-Labeled Indications and Dosage (Adult)
Ixekizumab is administered by subcutaneous injection. The recommended dose is 160 mg (two 80 mg injections) at Week 0, followed by 80 mg at Weeks 2, 4, 6, 8, 10, and 12, then 80 mg every 4 weeks.
Tuberculosis Assessment Prior to Initiation of Ixekizumab
Evaluate patients for tuberculosis (TB) infection prior to initiating treatment with Ixekizumab.
Important Administration Instructions
Ixekizumab is intended for use under the guidance and supervision of a physician. Patients may self-inject after training in subcutaneous injection technique using the autoinjector or prefilled syringe. Administer each injection at a different anatomic location (such as upper arms, thighs or any quadrant of abdomen) than the previous injection, and not into areas where the skin is tender, bruised, erythematous, indurated or affected by psoriasis. Administration of Ixekizumab in the upper, outer arm may be performed by a caregiver or healthcare provider.
If a dose is missed, administer the dose as soon as possible. Thereafter, resume dosing at the regular scheduled time.
Preparation for Use of Ixekizumab Autoinjector and Prefilled Syringe
Inspect Ixekizumab formulation visually for particulate matter and discoloration prior to administration. Ixekizumab formulation is a clear and colorless to slightly yellow solution. Do not use if the liquid contains visible particles, is discolored or cloudy (other than clear and colorless to slightly yellow). Ixekizumab formulation does not contain preservatives, therefore discard any unused product remaining in the autoinjector or prefilled syringe.
Off-Label Use and Dosage (Adult)
There is limited information regarding Off-Label Guideline-Supported Use of Ixekizumab in adult patients.
There is limited information regarding Off-Label Non–Guideline-Supported Use of Ixekizumab in adult patients.
Pediatric Indications and Dosage
FDA-Labeled Indications and Dosage (Pediatric)
FDA Package Insert for Ixekizumab contains no information regarding Pediatric Indications and Dosage.
Off-Label Use and Dosage (Pediatric)
There is limited information regarding Off-Label Guideline-Supported Use of Ixekizumab in pediatric patients.
There is limited information regarding Off-Label Non–Guideline-Supported Use of Ixekizumab in pediatric patients.
Ixekizumab may increase the risk of infection. In clinical trials, the Ixekizumab treated group had a higher rate of infections than the placebo group (27% vs. 23%). Upper respiratory tract infections, oral candidiasis, conjunctivitis and tinea infections occurred more frequently in the Ixekizumab treated group than in the placebo group.
Instruct patients treated with Ixekizumab to seek medical advice if signs or symptoms of clinically important chronic or acute infection occur. If a patient develops a serious infection or is not responding to standard therapy, monitor the patient closely and discontinue Ixekizumab until the infection resolves.
Pre-treatment Evaluation for Tuberculosis
Evaluate patients for tuberculosis (TB) infection prior to initiating treatment with Ixekizumab. Do not administer to patients with active TB infection. Initiate treatment of latent TB prior to administering Ixekizumab. Consider anti-TB therapy prior to initiating Ixekizumab in patients with a past history of latent or active TB in whom an adequate course of treatment cannot be confirmed. Patients receiving Ixekizumab should be monitored closely for signs and symptoms of active TB during and after treatment.
Serious hypersensitivity reactions, including angioedema and urticaria (each ≤0.1%), occurred in the Ixekizumab group in clinical trials. If a serious hypersensitivity reaction occurs, discontinue Ixekizumab immediately and initiate appropriate therapy.
Inflammatory Bowel Disease
Crohn's disease and ulcerative colitis, including exacerbations, occurred at a greater frequency in the Ixekizumab group (Crohn's disease 0.1%, ulcerative colitis 0.2%) than the placebo group (0%) during the 12-week, placebo-controlled period. During Ixekizumab treatment, monitor for onset or exacerbation of inflammatory bowel disease.
Prior to initiating therapy with Ixekizumab, consider completion of all age appropriate immunizations according to current immunization guidelines. Avoid use of live vaccines in patients treated with Ixekizumab. No data are available on the response to live or inactive vaccines.
Clinical Trials Experience
The following adverse drug reactions are discussed in greater detail in other sections of the label:
Because clinical trials are conducted under widely varying and controlled conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice.
Weeks 0 to 12:
Three placebo-controlled trials in subjects with plaque psoriasis were integrated to evaluate the safety of Ixekizumab compared to placebo for up to 12 weeks. A total of 1167 subjects (mean age 45 years; 66% men; 94% White) with plaque psoriasis received Ixekizumab (160 mg at Week 0, 80 mg every two weeks [Q2W] for 12 weeks) subcutaneously. In two of the trials, the safety of Ixekizumab (use up to 12 weeks) was also compared with an active comparator, U.S. approved etanercept.
In the 12-week, placebo-controlled period, adverse events occurred in 58% of the Ixekizumab Q2W group (2.5 per subject-year of follow-up) compared with 47% of the placebo group (2.1 per subject-year of follow-up). Serious adverse events occurred in 2% of the Ixekizumab group (0.07 per subject-year of follow-up), and in 2% of the placebo group (0.07 per subject-year of follow-up).
Table 1 summarizes the adverse reactions that occurred at a rate of at least 1% and at a higher rate in the Ixekizumab group than in the placebo group during the 12-week placebo-controlled period of the pooled clinical trials.
Adverse reactions that occurred at rates less than 1% in the Ixekizumab group and more frequently than in the placebo group during the 12-week induction period included rhinitis, oral candidiasis, urticaria, influenza, conjunctivitis, inflammatory bowel disease, and angioedema.
Weeks 13 to 60:
A total of 332 subjects received the recommended maintenance regimen of Ixekizumab 80 mg dosed every 4 weeks.
During the maintenance period (Weeks 13 to 60), adverse events occurred in 80% of subjects treated with Ixekizumab (1.0 per subject-year of follow-up) compared to 58% of subjects treated with placebo (1.1 per subject-year of follow-up). Serious adverse events were reported in 4% of subjects treated with Ixekizumab (0.05 per subject-year of follow-up) and none in the subjects treated with placebo.
Weeks 0 to 60:
Over the entire treatment period (Weeks 0 to 60), adverse events were reported in 67% of subjects treated with Ixekizumab (1.4 per subject-year of follow-up) compared to 48% of subjects treated with placebo (2.0 per subject-year of follow-up). Serious adverse events were reported in 3% of subjects treated with Ixekizumab (0.06 per subject-year of follow-up), and in 2% of subjects treated with placebo (0.06 per subject-year of follow-up).
Specific Adverse Drug Reactions
Injection Site Reactions
The most frequent injection site reactions were erythema and pain. Most injection site reactions were mild-to-moderate in severity and did not lead to discontinuation of Ixekizumab.
In the 12-week, placebo-controlled period of the clinical trials in plaque psoriasis, infections occurred in 27% of subjects treated with Ixekizumab (1.2 per subject-year of follow-up) compared to 23% of subjects treated with placebo (1.0 per subject-year of follow-up). Serious infections occurred in 0.4% of subjects treated with Ixekizumab (0.02 per subject-year of follow-up) and in 0.4% of subjects treated with placebo (0.02 per subject-year of follow-up).
During the maintenance treatment period (Weeks 13 to 60), infections occurred in 57% of subjects treated with Ixekizumab (0.70 per subject-year of follow-up) compared to 32% of subjects treated with placebo (0.61 per subject-year of follow-up). Serious infections occurred in 0.9% of subjects treated with Ixekizumab (0.01 per subject-year of follow-up) and none in the subjects treated with placebo.
Over the entire treatment period (Weeks 0 to 60), infections were reported in 38% of subjects treated with Ixekizumab (0.83 per subject-year of follow-up) compared to 23% of subjects treated with placebo (1.0 per subject-year of follow-up). Serious infections occurred in 0.7% of subjects treated with Ixekizumab (0.02 per subject-year of follow-up), and in 0.4% of subject treated with placebo (0.02 per subject-year of follow-up).
Laboratory Assessment of Cytopenia
Over the entire treatment period (Weeks 0 to 60), neutropenia occurred in 11% of subjects treated with Ixekizumab (0.24 per subject-year of follow-up) compared to 3% of subjects treated with placebo (0.14 per subject-year of follow-up). In subjects treated with Ixekizumab, the incidence rate of neutropenia during Weeks 13 to 60 was lower than the incidence rate during Weeks 0 to 12.
In the 12-week, placebo-controlled period, neutropenia ≥ Grade 3 (<1,000 cells/mm3) occurred in 0.2% of the Ixekizumab group (0.007 per subject-year of follow-up) compared to 0.1% of the placebo group (0.006 per subject-year of follow-up). The majority of cases of neutropenia were either Grade 2 (2% for Ixekizumab 80 mg Q2W versus 0.3% for placebo; ≥1,000 to <1,500 cells/mm3) or Grade 1 (7% for Ixekizumab 80 mg Q2W versus 3% for placebo; ≥1,500 cells/mm3 to ˂2,000 cells/mm3). Neutropenia in the Ixekizumab group was not associated with an increased rate of infection compared to the placebo group.
Ninety eight percent of cases of thrombocytopenia were Grade 1 (3% for Ixekizumab 80 mg Q2W versus 1% for placebo; ≥75,000 cells/mm3 to <150,000 cells/mm3). Thrombocytopenia in subjects treated with Ixekizumab was not associated with an increased rate of bleeding compared to subjects treated with placebo.
Active Comparator Trials
In the two clinical trials that included an active comparator, the rate of serious adverse events during weeks zero to twelve was 0.7% for U.S. approved etanercept and 2% for Ixekizumab 80 mg Q2W, and the rate of discontinuation from adverse events was 0.7% for U.S. approved etanercept and 2% for Ixekizumab 80 mg Q2W. The incidence of infections was 18% for U.S. approved etanercept and 26% for Ixekizumab 80 mg Q2W. The rate of serious infections was 0.3% for both Ixekizumab 80 mg Q2W and U.S. approved etanercept.
As with all therapeutic proteins there is the potential for immunogenicity with Ixekizumab. By Week 12, approximately 9% of subjects treated with Ixekizumab every 2 weeks developed antibodies to ixekizumab. Approximately 22% of subjects treated with Ixekizumab at the recommended dosing regimen developed antibodies to ixekizumab during the 60-week treatment period. The clinical effects of antibodies to ixekizumab are dependent on the antibody titer; higher antibody titers were associated with decreasing drug concentration and clinical response.
Of the subjects who developed antibodies to ixekizumab during the 60-week treatment period, approximately 10%, which equates to 2% of subjects treated with Ixekizumab at the recommended dosing regimen, had antibodies that were classified as neutralizing. Neutralizing antibodies were associated with reduced drug concentrations and loss of efficacy.
However, the assay to test for neutralizing antibodies has limitations detecting neutralizing antibodies in the presence of ixekizumab; therefore, the incidence of neutralizing antibodies development could be underestimated.
The detection of antibody formation is highly dependent on the sensitivity and specificity of the assay. Additionally, the observed incidence of antibody (including neutralizing antibody) positivity in an assay may be influenced by several factors including assay methodology, sample handling, timing of sample collection, concomitant medications, and underlying disease. For these reasons, comparison of incidence of antibodies to Ixekizumab with the incidences of antibodies to other products may be misleading.
FDA Package Insert for Ixekizumab contains no information regarding Adverse Reactions.
Avoid use of live vaccines in patients treated with Ixekizumab.
Cytochrome P450 Substrates
The formation of CYP450 enzymes can be altered by increased levels of certain cytokines (e.g., IL-1, IL-6, IL-10, TNFα, IFN) during chronic inflammation. Thus, Ixekizumab, an antagonist of IL-17A, could normalize the formation of CYP450 enzymes.
Therefore, upon initiation or discontinuation of Ixekizumab in patients who are receiving concomitant drugs which are CYP450 substrates, particularly those with a narrow therapeutic index, consider monitoring for effect (e.g., for warfarin) or drug concentration (e.g., for cyclosporine) and consider dosage modification of the CYP450 substrate.
Use in Specific Populations
Pregnancy Category (FDA): There are no available data on Ixekizumab use in pregnant women to inform any drug associated risks. Human IgG is known to cross the placental barrier; therefore, Ixekizumab may be transmitted from the mother to the developing fetus. An embryofetal development study conducted in pregnant monkeys at doses up to 19 times the maximum recommended human dose (MRHD) revealed no evidence of harm to the developing fetus. When dosing was continued until parturition, neonatal deaths were observed at 1.9 times the MRHD. The clinical significance of these nonclinical findings is unknown.
The background risk of major birth defects and miscarriage for the indicated population is unknown. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2 to 4% and 15 to 20%, respectively.
- Animal Data
An embryofetal development study was conducted in cynomolgus monkeys administered ixekizumab. No malformations or embryofetal toxicity were observed in fetuses from pregnant monkeys administered ixekizumab weekly by subcutaneous injection during organogenesis to near parturition at doses up to 19 times the MRHD (on a mg/kg basis of 50 mg/kg/week). Ixekizumab crossed the placenta in monkeys.
In a pre- and post-natal development toxicity study, pregnant cynomolgus monkeys were administered weekly subcutaneous doses of ixekizumab up to 19 times the MRHD from the beginning of organogenesis to parturition. Neonatal deaths occurred in the offspring of two monkeys administered ixekizumab at 1.9 times the MRHD (on a mg/kg basis of 5 mg/kg/week) and two monkeys administered ixekizumab at 19 times the MRHD (on a mg/kg basis of 50 mg/kg/week). These neonatal deaths were attributed to early delivery, trauma, or congenital defect. The clinical significance of these findings is unknown. No ixekizumab-related effects on functional or immunological development were observed in the infants from birth through 6 months of age.
Pregnancy Category (AUS): There is no Australian Drug Evaluation Committee (ADEC) guidance on usage of Ixekizumab in women who are pregnant.
Labor and Delivery
There is no FDA guidance on use of Ixekizumab during labor and delivery.
There are no data on the presence of ixekizumab in human milk, the effects on the breastfed infant, or the effects on milk production. Ixekizumab was detected in the milk of lactating cynomolgus monkeys. The developmental and health benefits of breastfeeding should be considered along with the mother's clinical need for Ixekizumab and any potential adverse effects on the breastfed infant from Ixekizumab or from the underlying maternal condition.
The safety and effectiveness of Ixekizumab in pediatric patients (<18 years of age) have not been evaluated.
Of the 4204 psoriasis subjects exposed to Ixekizumab, a total of 301 were 65 years or older, and 36 subjects were 75 years or older. Although no differences in safety or efficacy were observed between older and younger subjects, the number of subjects aged 65 and over is not sufficient to determine whether they respond differently from younger subjects.
There is no FDA guidance on the use of Ixekizumab with respect to specific gender populations.
There is no FDA guidance on the use of Ixekizumab with respect to specific racial populations.
There is no FDA guidance on the use of Ixekizumab in patients with renal impairment.
There is no FDA guidance on the use of Ixekizumab in patients with hepatic impairment.
Females of Reproductive Potential and Males
There is no FDA guidance on the use of Ixekizumab in women of reproductive potentials and males.
There is no FDA guidance one the use of Ixekizumab in patients who are immunocompromised.
Administration and Monitoring
There is limited information regarding Ixekizumab Administration in the drug label.
There is limited information regarding Ixekizumab Monitoring in the drug label.
There is limited information regarding the compatibility of Ixekizumab and IV administrations.
In the event of overdosage, monitor the patient for any signs or symptoms of adverse reactions and institute appropriate symptomatic treatment immediately.
Mechanism of Action
Ixekizumab is a humanized IgG4 monoclonal antibody that selectively binds with the interleukin 17A (IL-17A) cytokine and inhibits its interaction with the IL-17 receptor. IL-17A is a naturally occurring cytokine that is involved in normal inflammatory and immune responses. Ixekizumab inhibits the release of proinflammatory cytokines and chemokines.
There is limited information regarding Ixekizumab Structure in the drug label.
No formal pharmacodynamic studies have been conducted with Ixekizumab.
Steady-state concentrations were achieved by Week 8 following the 160 mg starting dose and 80 mg every 2 weeks dosing regimen; the mean ±SD steady-state trough concentration was 9.3 ±5.3 mcg/mL. Steady-state concentrations were achieved approximately 10 weeks after switching from the 80 mg every 2 weeks dosing regimen to the 80 mg every 4 weeks dosing regimen at Week 12. The mean ±SD steady-state trough concentration was 3.5 ±2.5 mcg/mL.
In studies of subjects with plaque psoriasis, ixekizumab bioavailability ranged from 60% to 81% following subcutaneous injection. Administration of ixekizumab via injection in the thigh achieved a higher bioavailability relative to that achieved using other injection sites including the arm and abdomen.
The metabolic pathway of ixekizumab has not been characterized. As a humanized IgG4 monoclonal antibody ixekizumab is expected to be degraded into small peptides and amino acids via catabolic pathways in the same manner as endogenous IgG.
Ixekizumab clearance and volume of distribution increase as body weight increases.
- Dose Linearity
Carcinogenesis, Mutagenesis, Impairment of Fertility
Animal studies have not been conducted to evaluate the carcinogenic or mutagenic potential of Ixekizumab. Moreover published literature is mixed on potential effects on malignancy risk due to the inhibition of IL-17A activity, the pharmacological action of Ixekizumab. Some published literature suggests that IL-17A directly promotes cancer cell invasion, suggesting a potential beneficial effect by Ixekizumab, whereas other reports indicate IL-17A promotes T-cell mediated tumor rejection, suggesting a potential adverse effect by Ixekizumab. However, neutralization of IL-17A with Ixekizumab has not been studied in these models. Depletion of IL-17A with a neutralizing antibody inhibited tumor development in mice, suggesting a potential beneficial effect by Ixekizumab. The relevance of experimental findings in mouse models for malignancy risk in humans is unknown.
No effects on fertility parameters such as reproductive organs, menstrual cycle length, or sperm analysis were observed in sexually mature cynomolgus monkeys that were administered ixekizumab for 13 weeks at a subcutaneous dose of 50 mg/kg/week (19 times the MRHD on a mg/kg basis). The monkeys were not mated to evaluate fertility.
Three multicenter, randomized, double-blind, placebo-controlled trials (Trials 1, 2, and 3) enrolled a total of 3866 subjects 18 years of age and older with plaque psoriasis who had a minimum body surface area involvement of 10%, a static Physician Global Assessment (sPGA) score of ≥3 in the overall assessment (plaque thickness/induration, erythema, and scaling) of psoriasis on a severity scale of 0 to 5, a Psoriasis Area and Severity Index (PASI) score ≥12, and who were candidates for phototherapy or systemic therapy.
In all three trials, subjects were randomized to either placebo or Ixekizumab (80 mg every two weeks [Q2W]) for 12 weeks, following a 160 mg starting dose. In the two active comparator trials (Trials 2 and 3), subjects were also randomized to receive U.S. approved etanercept 50 mg twice weekly for 12 weeks.
All three trials assessed the changes from baseline to Week 12 in the two co-primary endpoints: 1) PASI 75, the proportion of subjects who achieved at least a 75% reduction in the PASI composite score that takes into consideration both the percentage of body surface area affected and the nature and severity of psoriatic changes (induration, erythema and scaling) within the affected regions, and 2) sPGA of “0” (clear) or “1” (minimal), the proportion of subjects with an sPGA 0 or 1 and at least a 2-point improvement.
Other evaluated outcomes included the proportion of subjects with an sPGA score of 0 (clear), a reduction of at least 90% in PASI (PASI 90), a reduction of 100% in PASI (PASI 100), and an improvement of itch severity as measured by a reduction of at least 4 points on an 11-point itch Numeric Rating Scale.
Subjects in all treatment groups had a median baseline PASI score ranging from approximately 17 to 18. Baseline sPGA score was severe or very severe in 51% of subjects in Trial 1, 50% in Trial 2, and 48% in Trial 3.
Of all subjects, 44% had received prior phototherapy, 49% had received prior conventional systemic therapy, and 26% had received prior biologic therapy for the treatment of psoriasis. Of the subjects who had received prior biologic therapy, 15% had received at least one anti-TNF alpha agent, and 9% had received an anti-IL 12/IL23. A total of 23% of study subjects had a history of psoriatic arthritis.
Clinical Response at Week 12
The results of Trials 1, 2, and 3 are presented in Table 2.
Examination of age, gender, race, body weight, and previous treatment with a biologic did not identify differences in response to Ixekizumab among these subgroups at Week 12.
Subjects treated with Ixekizumab 80 mg Q2W experienced improvement in itch severity when compared to placebo at Week 12.
An integrated analysis of the U.S. sites in the two active comparator studies using U.S. approved etanercept, Ixekizumab demonstrated superiority to U.S. approved etanercept (50 mg twice weekly) on sPGA and PASI scores during the 12 week treatment period. The respective response rates for Ixekizumab 80 mg Q2W and U.S. approved etanercept 50 mg twice weekly were: sPGA of 0 or 1 (73% and 27%); PASI 75 (87% and 41%); sPGA of 0 (34% and 5%); PASI 90 (64% and 18%), and PASI 100 (34% and 4%).
Maintenance and Durability of Response
To evaluate the maintenance and durability of response, subjects originally randomized to Ixekizumab and who were responders at Week 12 (i.e., sPGA of 0 or 1) in Trial 1 and Trial 2 were re-randomized to an additional 48 weeks of either a maintenance dose of Ixekizumab 80 mg Q4W (every four weeks) or placebo. Non-responders (sPGA >1) at Week 12 and subjects who relapsed (sPGA ≥3) during the maintenance period were placed on Ixekizumab 80 mg Q4W.
For responders at Week 12, the percentage of subjects who maintained this response (sPGA 0 or 1) at Week 60 (48 weeks following re-randomization) in the integrated trials (Trial 1 and Trial 2) was higher for subjects treated with Ixekizumab 80 mg Q4W (75%) compared to those treated with placebo (7%).
For responders at Week 12 who were re-randomized to treatment withdrawal (i.e., placebo), the median time to relapse (sPGA ≥3) was 164 days in the integrated trials. Among these subjects, 66% regained a response of at least 0 or 1 on the sPGA within 12 weeks of restarting treatment with Ixekizumab 80 mg Q4W.
Ixekizumab injection is a sterile, preservative free, clear and colorless to slightly yellow solution available in a single-dose prefilled autoinjector or a single-dose prefilled syringe to deliver 80 mg ixekizumab.
Ixekizumab is supplied as:
Ixekizumab is sterile and preservative-free. Discard any unused portion.
- Ixekizumab must be protected from light until use.
- Store refrigerated at 2°C to 8°C (36°F to 46°F).
- Do not freeze. Do not use Ixekizumab if it has been frozen.
- Do not shake.
- Discard the Ixekizumab single-dose autoinjector or syringe after use in a puncture-resistant container.
- Not made with natural rubber latex.
Package and Label Display Panel
Patient Counseling Information
Advise the patient and/or caregiver to read the FDA-approved patient labeling (Medication Guide and Instructions for Use) before the patient starts using Ixekizumab, and each time the prescription is renewed, as there may be new information they need to know.
- Instructions on Self-Administration: Provide guidance to patients and caregivers on proper subcutaneous injection technique, including aseptic technique, and how to use the autoinjector or prefilled syringe correctly.
- Infection: Inform patients that Ixekizumab may lower the ability of their immune system to fight infections. Instruct patients of the importance of communicating any history of infections to the healthcare provider, and contacting their healthcare provider if they develop any symptoms of infection.
- Allergic Reactions: Advise patients to seek immediate medical attention if they experience any symptoms of serious hypersensitivity reactions.
Precautions with Alcohol
Alcohol-Ixekizumab interaction has not been established. Talk to your doctor about the effects of taking alcohol with this medication.
There is limited information regarding Ixekizumab Brand Names in the drug label.
Look-Alike Drug Names
There is limited information regarding Ixekizumab Look-Alike Drug Names in the drug label.
The contents of this FDA label are provided by the National Library of Medicine.