etanercept

etanercept

(ee tah ner' sept)

Enbrel

Pregnancy Category B

Drug classes

Antarthritic

Disease-modifying antirheumatic drug (DMARD)

Therapeutic actions

Genetically engineered tumor necrosis factor receptors from Chinese hamster ovary cells; keep inflammatory response to autoimmune disease in check by reacting with and deactivating free-floating tumor necrosis factor released by active leukocytes.

Indications

·        Reduction of the signs and symptoms that induce major clinical response, inhibit the progression of structural damage, and improve physical function in patients with moderately to severely active rheumatoid arthritis; to delay the structural damage associated with rheumatoid arthritis; or may be used in combination with methotrexate when patients do not respond to methotrexate alone

·        Polyarticular-course juvenile rheumatoid arthritis in patients who have not had an adequate response to one or more antirheumatic drugs

·        Reduction of signs and symptoms and to improve function in patients with psoriatic arthritis; may be used alone or in combination with methotrexate

·        Treatment of ankylosing spondylitis

·        Treatment of adult patients with chronic moderate to severe plaque psoriasis who are candidates for systemic therapy or phototherapy.

Contraindications and cautions

·        Contraindicated with allergy to etanercept or Chinese hamster products, lactation, pregnancy, cancer, severe infection including sepsis, CNS demyelinatingdisorders, myelosuppression.

·        Use cautiously with renal or hepatic disorders, any infection, CHF.

Available forms

Powder for injection—25 mg

Dosages

ADULTS

25 mg subcutaneously twice weekly with 72–96 hr between doses or 50 mg subcutaneously once weekly.

Plaque psoriasis: 50 mg/dose subcutaneously twice weekly for 3 mo; then maintenance dose of 50 mg/wk subcutaneously.

PEDIATRIC PATIENTS 4-17 YR

0.4 mg/kg subcutaneously two times a week with 72–96 hr between doses to a maximum 25 mg/dose or 0.8 mg/kg subcutaneously once weekly.

PEDIATRIC PATIENTS < 4 YR

Safety and efficacy not established.

Pharmacokinetics

Route	Onset	Peak
SC	Slow	72 hr

Metabolism: Tissue; T_1/2: 115 hr

Distribution: Crosses placenta; may enter breast milk

Excretion: Tissues

Adverse effects

·        CNS: CNS demyelinating disorders (MS, myelitis, optic neuritis)

·        GI: Abdominal pain, dyspepsia

·        Hematologic: Pancytopenia

·        Respiratory: URIs, congestion, rhinitis, cough, pharyngitis

·        Other: Irritation at injection site; increased risk of infections, cancers; ANA development; headache; autoimmune diseases

Nursing considerations

Assessment

·        History: Allergy to etanercept or Chinese hamster products; pregnancy, lactation; serious infections; cancer; CNS demyelinating disorders,myelosuppression

·        Physical: Skin lesions, color; R, adventitious sounds; injection site evaluation; range-of-motion to monitor drug effectiveness; CNS—neurologic evaluation, reflexes; CBC

Interventions

·        WARNING: Obtain a baseline and periodic CBC; discontinue drug at signs of severe bone marrow suppression.

·        WARNING: Obtain baseline values of neurologic function; discontinue drug at any sign of CNS demyelinating disorders.

·        Advise patient that this drug does not cure the disease and appropriate therapies for rheumatoid arthritis should be used.

·        Reconstitute for injection by slowly injecting 1 mL sterile bacteriostatic water provided with powder into the vial; swirl gently, do not shake; avoid foaming; liquid should be clear and free of particulate matter; use within 6 hr of reconstitution. Do not mix with any other medications.

·        Rotate injection sites between abdomen, thigh, and upper arm. Maintain a chart to ensure that sites are rotated regularly.

·        Teach patient and a significant other how to reconstitute and administer subcutaneous injections; observe the process periodically.

·        Monitor patient for any sign of infection; discontinue drug if infection occurs.

·        Evaluate drug effectiveness periodically; 1–2 wk may be required before any change is noted; if no response has occurred within 3 mo, discontinue drug.

·        Do not administer drug with any vaccinations; allow at least 2–3 wk between starting this drug and a vaccination.

·        Protect patient from exposure to infections and ensure routine physical examinations and monitoring for potential cancers and autoimmune diseases.

Teaching points

·        Take this drug exactly as prescribed. Note that this drug does not cure rheumatoid arthritis and appropriate therapies to deal with the disease should be followed. You and a significant other should learn how to prepare the drug and to administer subcutaneous injections. Prepare a chart of injection sites to ensure that sites are rotated on a regular basis. Consult with your health care provider about proper disposal of needles and syringes.

·        Arrange for frequent, regular medical follow-up visits, including blood tests to follow the effects of the drug on your body.

·        You may experience these side effects: Signs and symptoms of upper respiratory tract infections, cough, sore throat (consult with your health care provider for potential treatment if this becomes severe); headache (analgesics may be available to help); increased susceptibility to infections (avoid crowded areas and people who might have infections; use strict handwashing and good hygiene).

·        Report fever, chills, lethargy; rash, difficulty breathing; swelling; worsening of arthritis; severe diarrhea.

Adverse effects in Italic are most common; those in Bold are life-threatening.