Rheumatology Drugs at a Glance, Part 2: Psoriasis

Etanercept (Enbrel):¹⁵ injection

Drug class: DMARD, TNFi

Boxed warning: Refer to *ISI (left)

Warnings & Precautions

• Do not start etanercept during an active infection. If an infection develops, monitor carefully, and stop etanercept if the infection becomes serious.
• Consider empiric anti-fungal therapy for patients at risk (those who reside in or travel to regions where mycoses are endemic) for invasive fungal infections who develop a severe systemic illness on etanercept.
• Demyelinating disease, exacerbation or new onset, may occur.
• Cases of lymphoma have been observed in patients receiving TNFi’s.
• Congestive heart failure, worsening or new onset, may occur.
• Advise patients to seek immediate medical attention if symptoms of pan­cytopenia or aplastic anemia develop, and consider stopping etanercept.
• Monitor HBV carriers for reactivation during and following therapy. If reactivation occurs, consider stopping etanercept and beginning anti-viral therapy.
• Anaphylaxis or serious allergic reactions may occur.
• Stop etanercept if lupus-like syndrome or autoimmune hepatitis develops.

Dosage & Administration

Etanercept is administered by subcutaneous injection.

Adults: The starting dose is 50 mg twice weekly for three months. The maintenance dose is 50 mg once weekly.

Pediatrics:

• 63 kg (138 lbs.) or more: the recommended dose is 50 mg weekly.
• Less than 63 kg (138 lbs.): the recommended dose is 0.8 mg/kg weekly.

Commentary: Etanercept is approved for adult and pediatric plaque psoriasis. It is the first and only systemic therapy to treat children aged 4-17 years for chronic moderate to severe plaque psoriasis. The most common adverse reactions (≥5%) are infections and injection-site reactions.

Infliximab (Remicade):¹⁶ infusion

Biosimilar(s): Infliximab-dyyb (Inflectra),¹⁷ Infliximab-abda (Renflexis),¹⁸ Infliximab-qbtx (Ixifi)¹⁹

Drug class: DMARD, TNFi

Boxed warning: Refer to *ISI (above) and

• Fatal hepatosplenic T-cell lymphoma (HSTCL) have been reported in patients treated with TNFi’s, post­marketing. All infliximab cases occurred in IBD patients, who were mostly adolescent or young adult males. All had received azathioprine or 6-mercaptopurine concomitantly with infliximab at or prior to diagnosis.

Warnings & Precautions

• Do not give infliximab during an active infection. If an infection develops, monitor carefully and stop infliximab if the infection becomes serious.
• Invasive fungal infections—for patients who develop a systemic illness on infliximab, consider empiric anti-fungal therapy for those who reside or travel to regions where mycoses are endemic
• The incidence of malignancies, including lymphoma, was greater in infliximab-treated patients than in controls. Due to the risk of HSTCL, carefully assess the risk/benefit especially in IBD patients, in males, and if receiving azathioprine or 6-mercaptopurine treatment.
• HBV reactivation can occur. Test for HBV infection before starting infliximab. Monitor HBV carriers during and several months after therapy. If reactivation occurs, stop infliximab and begin anti-viral therapy.
• Hepatotoxicity—rare severe hepatic reactions, some fatal or necessitating liver transplantation have occurred. Stop infliximab in cases of jaundice and/or marked liver enzyme elevations.
• Heart failure, new onset or worsening symptoms, may occur.
• Cytopenias—advise patients to seek immediate medical attention if signs and symptoms develop, and consider stopping infliximab.
• Hypersensitivity—serious infusion reactions including anaphylaxis or serum sickness-like reactions may occur.
• Demyelinating disease, exacerbation or new onset, may occur.
• Lupus-like syndrome—stop infliximab if syndrome develops.
• Live vaccines or therapeutic infectious agents should not be given with infliximab.

Dosage & Administration

Infliximab is administered by intravenous infusion over a period of not less than two hours. The recommended dose is 5 mg/kg given as an intravenous induction regimen at 0, 2 and 6 weeks, followed by a maintenance regimen of 5 mg/kg every eight weeks.

Commentary: The FDA approved infliximab for treatment of psoriasis based on data from two multicenter clinical trials that enrolled 1,200 patients. The results showed that a majority of infliximab-treated patients achieved clinically significant levels of skin clearance with induction and every-eight-week maintenance therapy. The most common adverse reactions (≥10%) are infections (e.g., upper respiratory, sinusitis, pharyngitis), infusion-related reactions, headache and abdominal pain.