Ixekizumab, sold under the brand name Taltz, is an injectable medication for the treatment of

autoimmune disease An autoimmune disease is a condition arising from an abnormal immune response to a functioning body part. At least 80 types of autoimmune diseases have been identified, with some evidence suggesting that there may be more than 100 types. Nearly a ...

s. Chemically, it is a form of a humanized

monoclonal antibody A monoclonal antibody (mAb, more rarely called moAb) is an antibody produced from a cell Lineage made by cloning a unique white blood cell. All subsequent antibodies derived this way trace back to a unique parent cell. Monoclonal antibodies ca ...

. The substance acts by binding

interleukin 17A Interleukin-17A is a protein that in humans is encoded by the ''IL17A'' gene. In rodents, IL-17A used to be referred to as CTLA8, after the similarity with a viral gene (). Function The protein encoded by this gene is a proinflammatory cytokin ...

and neutralizing it, reducing

inflammation Inflammation (from la, wikt:en:inflammatio#Latin, inflammatio) is part of the complex biological response of body tissues to harmful stimuli, such as pathogens, damaged cells, or Irritation, irritants, and is a protective response involving im ...

. The most common side effects include upper respiratory infections, injection site reactions and fungal (tinea) infections. The drug was developed by

Eli Lilly and Co. Eli Lilly and Company is an American pharmaceutical company headquartered in Indianapolis, Indiana, with offices in 18 countries. Its products are sold in approximately 125 countries. The company was founded in 1876 by, and named after, Colonel ...

and is approved for the treatment of

plaque psoriasis Psoriasis is a long-lasting, noncontagious autoimmune disease characterized by skin plaque, raised areas of abnormal skin. These areas are erythema, red, pink, or purple, Xeroderma, dry, itchy, and scaly. Psoriasis varies in severity from small ...

in the European Union and the United States.

Medical uses

In the United States, ixekizumab is

indicated In medicine, an indication is a valid reason to use a certain test, medication, procedure, or surgery. There can be multiple indications to use a procedure or medication. An indication can commonly be confused with the term diagnosis. A diagnosis ...

for the treatment of adults with moderate-to-severe plaque psoriasis who are candidates for systemic therapy or phototherapy, active psoriatic arthritis, active ankylosing spondylitis, and active non-radiographic axial spondyloarthritis with objective signs of inflammation. In the European Union it is indicated for the treatment of moderate-to-severe plaque psoriasis and as a second-line therapy for active

psoriatic arthritis Psoriatic arthritis is a long-term inflammatory arthritis that occurs in people affected by the autoimmune disease psoriasis. The classic feature of psoriatic arthritis is swelling of entire fingers and toes with a sausage-like appearance. Thi ...

. In studies, the drug reduced the

Psoriasis Area and Severity Index Psoriasis Area and Severity Index (PASI) is the most widely used tool for the measurement of severity of psoriasis. PASI combines the assessment of the severity of lesions and the area affected into a single score in the range 0 (no disease) to ...

by at least 75% (PASI75) in 82–89% of patients during the first three months of treatment (depending on the dosing scheme), and 40% of patients experienced a complete absence of psoriasis symptoms (PASI100). In the

placebo A placebo ( ) is a substance or treatment which is designed to have no therapeutic value. Common placebos include inert tablets (like sugar pills), inert injections (like Saline (medicine), saline), sham surgery, and other procedures. In general ...

group, PASI75 was reached in 4% of patients, and PASI100 in none; in the group of patients receiving

etanercept Etanercept, sold under the brand name Enbrel among others, is a biologic medical product that is used to treat autoimmune diseases by interfering with tumor necrosis factor (TNF), a soluble inflammatory cytokine, by acting as a TNF inhibitor. It h ...

, an older anti-psoriasis drug, PASI75 was reached in 48%. Until the 60th study week, 11–44% of ixekizumab treated patients relapsed (again, depending on the dosing scheme), as compared to 84% under placebo.

Contraindications

The medication is contraindicated for patients with certain infections such as active

tuberculosis Tuberculosis (TB) is an infectious disease usually caused by '' Mycobacterium tuberculosis'' (MTB) bacteria. Tuberculosis generally affects the lungs, but it can also affect other parts of the body. Most infections show no symptoms, in ...

Adverse effects

In studies, ixekizumab increased the rate of infections (27% of ixekizumab treated patients, compared to 23% under

), including severe ones (0.6% versus 0.4% under placebo). Other common side effects included injection site pain (13–17% versus 3%),

oropharyngeal The pharynx (plural: pharynges) is the part of the throat behind the mouth and nasal cavity, and above the oesophagus and trachea (the tubes going down to the stomach and the lungs). It is found in vertebrates and invertebrates, though its struct ...

pain (1%) and

nausea Nausea is a diffuse sensation of unease and discomfort, sometimes perceived as an urge to vomit. While not painful, it can be a debilitating symptom if prolonged and has been described as placing discomfort on the chest, abdomen, or back of the ...

(1–2%).

Overdose

Up to fourfold doses have been given in studies without causing serious side effects.

Interactions

No interaction studies have been done. Ixekizumab and interleukin 17 are not known to interact with

cytochrome P450 Cytochromes P450 (CYPs) are a Protein superfamily, superfamily of enzymes containing heme as a cofactor (biochemistry), cofactor that functions as monooxygenases. In mammals, these proteins oxidize steroids, fatty acids, and xenobiotics, and are ...

(CYP) liver enzymes. Since inflammation suppresses CYP activity, it is theorized that ixekizumab could neutralize this effect and lower

blood plasma Blood plasma is a light amber-colored liquid component of blood in which blood cells are absent, but contains proteins and other constituents of whole blood in suspension. It makes up about 55% of the body's total blood volume. It is the intra ...

concentrations of drugs that are metabolized by CYP enzymes, such as

warfarin Warfarin, sold under the brand name Coumadin among others, is a medication that is used as an anticoagulant (blood thinner). It is commonly used to prevent blood clots such as deep vein thrombosis and pulmonary embolism, and to prevent strok ...

Pharmacology

Mechanism of action

Ixekizumab binds to interleukin 17 (IL-17A), a pro-inflammatory

cytokine Cytokines are a broad and loose category of small proteins (~5–25 kDa) important in cell signaling. Cytokines are peptides and cannot cross the lipid bilayer of cells to enter the cytoplasm. Cytokines have been shown to be involved in autocrin ...

, and blocks its action. Among other things, IL-17A stimulates proliferation and activation of

keratinocyte Keratinocytes are the primary type of Cell (biology), cell found in the epidermis (skin), epidermis, the outermost layer of the skin. In humans, they constitute 90% of epidermal skin cells. Basal cells in the stratum basale, basal layer (''str ...

s in the skin. This mechanism is similar to that of another anti-psoriasis antibody,

brodalumab Brodalumab, sold under the brand name Siliq in the US and Kyntheum in the EU, is a human monoclonal antibody designed for the treatment of inflammatory diseases. In February 2017, it received US FDA approval to treat moderate to severe plaque ps ...

, which binds to the

interleukin-17 receptor Interleukin-17 receptor (IL-17R) is a cytokine receptor which belongs to new subfamily of receptors binding proinflammatory cytokine interleukin 17A, a member of IL-17 family ligands produced by T helper 17 cells (Th17). IL-17R family cons ...

. The antibody has affinity to the

homodimer In biochemistry, a protein dimer is a macromolecular complex formed by two protein monomers, or single proteins, which are usually non-covalently bound. Many macromolecules, such as proteins or nucleic acids, form dimers. The word ''dimer'' ha ...

IL-17A and the heterodimer IL-17A/F, but not to other members of the

interleukin 17 family Interleukin 17 family (IL17 family) is a family of pro-inflammatory cystine knot cytokines. They are produced by a group of T helper cell known as T helper 17 cell in response to their stimulation with IL-23. Originally, Th17 was identifie ...

Pharmacokinetics

After

subcutaneous injection Subcutaneous administration is the insertion of medications beneath the skin either by injection or infusion. A subcutaneous injection is administered as a bolus into the subcutis, the layer of skin directly below the dermis and epidermis, ...

, ixekizumab has a bioavailability of 54–90%. Highest blood plasma concentrations are reached after four to seven days after a single dose. With the usual dosing scheme (loading plus a dose every two weeks), steady state concentrations are reached in the eighth week on average. Like other

antibodies An antibody (Ab), also known as an immunoglobulin (Ig), is a large, Y-shaped protein used by the immune system to identify and neutralize foreign objects such as pathogenic bacteria and viruses. The antibody recognizes a unique molecule of the ...

, ixekizumab is probably degraded by

proteolysis Proteolysis is the breakdown of proteins into smaller polypeptides or amino acids. Uncatalysed, the hydrolysis of peptide bonds is extremely slow, taking hundreds of years. Proteolysis is typically catalysed by cellular enzymes called protease ...

. Its

elimination half-life Biological half-life (also known as elimination half-life, pharmacologic half-life) is the time taken for concentration of a biological substance (such as a medication) to decrease from its maximum concentration ( Cmax) to half of Cmax in the bl ...

is 13 days.

Chemistry

Ixekizumab is a complete monoclonal antibody of the subclass IgG₄, consisting of two light chains and two heavy chains linked by

disulfide bridge In biochemistry, a disulfide (or disulphide in British English) refers to a functional group with the structure . The linkage is also called an SS-bond or sometimes a disulfide bridge and is usually derived by the coupling of two thiol groups. In ...

s. Both heavy chains are

glycosylated Glycosylation is the reaction in which a carbohydrate (or 'glycan'), i.e. a glycosyl donor, is attached to a hydroxyl or other functional group of another molecule (a glycosyl acceptor) in order to form a glycoconjugate. In biology (but not alw ...

at the

asparagine Asparagine (symbol Asn or N) is an α-amino acid that is used in the biosynthesis of proteins. It contains an α-amino group (which is in the protonated −NH form under biological conditions), an α-carboxylic acid group (which is in the depro ...

in position 296. In the hinge region, a

serine Serine (symbol Ser or S) is an α-amino acid that is used in the biosynthesis of proteins. It contains an α-amino group (which is in the protonated − form under biological conditions), a carboxyl group (which is in the deprotonated − form un ...

is replaced by a

proline Proline (symbol Pro or P) is an organic acid classed as a proteinogenic amino acid (used in the biosynthesis of proteins), although it does not contain the amino group but is rather a secondary amine. The secondary amine nitrogen is in the prot ...

to reduce formation of half-antibodies and

heterodimer In biochemistry, a protein dimer is a macromolecular complex formed by two protein monomers, or single proteins, which are usually non-covalently bound. Many macromolecules, such as proteins or nucleic acids, form dimers. The word ''dimer'' has ...

s in the manufacturing process. The terminal

lysine Lysine (symbol Lys or K) is an α-amino acid that is a precursor to many proteins. It contains an α-amino group (which is in the protonated form under biological conditions), an α-carboxylic acid group (which is in the deprotonated −C ...

found in wild-type IgG₄ is removed. The antibody is produced in

Chinese hamster ovary cell Chinese hamster ovary (CHO) cells are an epithelial cell line derived from the ovary of the Chinese hamster, often used in biological and medical research and commercially in the production of recombinant therapeutic proteins. They have foun ...

History

Clinical trial Clinical trials are prospective biomedical or behavioral research studies on human participants designed to answer specific questions about biomedical or behavioral interventions, including new treatments (such as novel vaccines, drugs, dietar ...

s included a

Phase II trial The phases of clinical research are the stages in which scientists conduct experiments with a health intervention to obtain sufficient evidence for a process considered effective as a medical treatment. For drug development, the clinical phases ...

of patients with moderate to severe psoriasis, and a Phase III

open-label trial An open-label trial, or open trial, is a type of clinical trial in which information is not withheld from trial participants. In particular, both the researchers and participants know which treatment is being administered. This contrasts with a do ...

. Ixekizumab was approved by the US

Food and Drug Administration The United States Food and Drug Administration (FDA or US FDA) is a List of United States federal agencies, federal agency of the United States Department of Health and Human Services, Department of Health and Human Services. The FDA is respon ...

(FDA) in March 2016, for the treatment of adults with moderate-to-severe plaque psoriasis and by the

European Medicines Agency The European Medicines Agency (EMA) is an agency of the European Union (EU) in charge of the evaluation and supervision of medicinal products. Prior to 2004, it was known as the European Agency for the Evaluation of Medicinal Products or Euro ...

(EMA) in April 2016. The safety and efficacy of ixekizumab were established in three randomized, placebo-controlled clinical trials with a total of 3,866 participants with plaque psoriasis who were candidates for systemic or phototherapy therapy. The FDA approved ixekizumab based on the evidence from three clinical trials of 1958 participants with moderate to severe psoriasis. The trials were conducted in the US, Canada, Europe, Russia, Mexico, Chile, Argentina, Japan and Australia. In December 2017, the FDA approved it for active psoriatic arthritis.

References

External links

* {{Portal bar , Medicine Eli Lilly and Company brands Immunosuppressants Monoclonal antibodies Disease-modifying antirheumatic drugs