Secukinumab is a human monoclonal antibody that targets IL-17A cytokine to downregulate inflammation in psoriasis, an autoimmune dermatological disease. The pathophysiology of psoriasis has not been fully established, however it is known that dysregulation of innate and adaptive immune responses plays part in the chronic inflammation associated with the disease. IL-17 represents is a six-membered family (IL-17A to F) of pleiotropic pro-inflammatory cytokines, expression of which is found to be elevated in psoriatic skin. These cytokines act on many different cell types and provide defense against different extracellular pathogens causing fungal or bacterial infections. IL-17 cytokines are produced by many cells involved in immune system defense, such as Th17, mast cells, neutrophils, and dendritic cells - all implicated in promoting inflammation. There is evidence linking IL-17 to pathogenesis of multiple autoimmune diseases including rheumatoid arthritis, spondyloarthritis, psoriasis, Crohn's disease, multiple sclerosis, and even atherosclerosis.

Secukinumab is a human interleukin-17A antagonist indicated for the treatment of:

• Moderate to severe plaque psoriasis in adult patients who are candidates for systemic therapy or phototherapy
• Adults with active psoriatic arthritis (PsA)
• Adults with active ankylosing spondylitis (AS)

Plaque Psoriasis-

1. Recommended dosage is 300 mg by subcutaneous injection at Weeks 0, 1, 2, 3, and 4 followed by 300 mg every 4 weeks. For some patients, a dose of 150 mg may be acceptable.

Psoriatic Arthritis-

1. For psoriatic arthritis patients with coexistent moderate to severe plaque psoriasis, use the dosage and administration for plaque psoriasis.

2. For other psoriatic arthritis patients administer with or without a loading dosage. The recommended dosage:

• With a loading dosage is 150 mg at weeks 0, 1, 2, 3, and 4 and every 4 weeks thereafter
• Without a loading dosage is 150 mg every 4 weeks
• If a patient continues to have active psoriatic arthritis, consider a dosage of 300 mg.

Ankylosing Spondylitis-

1. Administer with or without a loading dosage. The recommended dosage:

• With a loading dosage is 150 mg at weeks 0, 1, 2, 3, and 4 and every 4 weeks thereafter
• Without a loading dosage is 150 mg every 4 weeks

Serious hypersensitivity reaction to secukinumab or to any of the excipients.

Most common adverse reactions (greater than 1%) are nasopharyngitis, diarrhea, and upper respiratory tract infection.

Overdose Effects

Doses up to 30 mg/kg intravenously have been administered in clinical trials without dose-limiting toxicity. In the event of overdosage, it is recommended that the patient be monitored for any signs or symptoms of adverse reactions and appropriate symptomatic treatment be instituted immediately.

Infections: Serious infections have occurred. Caution should be exercised when considering the use of secukinumab in patients with a chronic infection or a history of recurrent infection. If a serious infection develops, discontinue secukinumab until the infection resolves.

Tuberculosis (TB): Prior to initiating treatment with secukinumab, evaluate for TB.

Inflammatory Bowel Disease: Cases of inflammatory bowel disease were observed in clinical trials. Caution should be exercised when prescribing secukinumab to patients with inflammatory bowel disease.

Hypersensitivity Reactions: If an anaphylactic reaction or other serious allergic reaction occurs, discontinue secukinumab immediately and initiate appropriate therapy.

Pregnancy & Lactation

Pregnancy: Limited available human data with secukinumab use in pregnant women are insufficient to inform a drug associated risk of adverse developmental outcomes. In an embryo-fetal development study, no adverse developmental effects were observed in infants born to pregnant monkeys after subcutaneous administration of secukinumab during organogenesis at doses up to 30 times the maximum recommended human dose

Lactation: It is not known whether secukinumab is excreted in human milk or absorbed systemically after ingestion. There are no data on the effects of secukinumab on the breastfed child or the effects on milk production. The developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for secukinumab and any potential adverse effects on the breastfed child from secukinumab or from the underlying maternal condition.