(1) Drug introduction

Infliximab (Infliximab) is a monoclonal antibody of TNF- formed by binding the Fab segment of mouse IgG to the Fc segment of human IgG. It can bind to soluble and transmembrane TNF- molecules, block their binding to TNF- receptors on the cell surface, and make TNF- lose its biological activity. The activity of TNF- plays an important role in the pathogenesis of psoriasis and contributes significantly to the symptoms of psoriasis.

(2) To treat the target population

Plaque psoriasis

Drug dose: intravenous, 5mg/kg, administered at 0, 2, 6 weeks, and thereafter every 8 weeks. Efficacy usually begins 2 weeks after administration, and usually peaks at 10 weeks. Medication should be discontinued if the improvement does not meet the effective target at 10 weeks, or if serious adverse reactions occur during treatment (such as an infection requiring antibiotic treatment), pregnancy, or surgery.

Arthropathic psoriasis

The method of administration is similar to plaque psoriasis. 58% of the patients achieved ACR20 improvement at week 14, 54%, 42% and 27% of the patients reached ACR20/50/70 at month 6, respectively. Sharp score indicated that the imaging progress of joint lesions was inhibited. Follow-up observation revealed that these improvements were sustained for up to 1 year. If at the 14th week after medication, the condition does not improve as effectively as expected, or if serious adverse reactions, pregnancy or surgery occur during treatment, the medication should be discontinued.

Other types of psoriasis

Infliximab is effective in the treatment of pustular and erythrodermic psoriasis and can be used as appropriate.

(3) Therapeutic conversion

When the traditional systemic treatment is switched to infliximab, the traditional systemic treatment (except methotrexate) is discontinued after 4 weeks to determine the severity of the disease and reduce the risk of infection. If infliximab therapy requires combined treatment with methotrexate, the latter is recommended at the smallest possible dose. When the disease worsens significantly after discontinuation of traditional systemic treatment, the original regimen can be continued until infliximab is effective during the treatment transition period. When switching between biological agents, the interval is 4 times the half-life of the previous drug.

(4) Combined with other systemic treatments

In clinical trials using Infliximab combined with methotrexate in the treatment of rheumatoid arthritis and arthropathic psoriasis, it was found that simultaneous administration of methotrexate not only increased the blood drug concentration of Infliximab, but also reduced the production of antibodies against infliximab, thus improving and maintaining its efficacy. There are no randomized controlled trials of infliximab combined with methotrexate in the treatment of psoriasis vulgaris.

(5) Treatment for special groups (children, pregnancy, breastfeeding, perioperative period, chronic hepatitis B, Hepatitis C, HIV patients, herpes, vaccines, etc.)

Although there have been a few reports of application in the above special groups, most studies tend to be conservative and generally advocate strict control and cautious use.

(6) Pre-treatment screening program

Similar to other TNF- inhibitors, except for TB infection, tests include chest radiograph and PPD, and t-SPOT testing should be performed if possible.

(7) Adverse drug reactions

The common adverse drug reactions mainly include infusion reaction and serum disease - like reaction. Rare adverse reactions include severe infection (e.g., tuberculosis) and malignancy (e.g., t-cell lymphoma of the liver and spleen, more common in children). Other rare but reversible side effects include systemic lupus erythematosus, hemocytopenia, multiple sclerosis and congestive heart failure.

(8) Monitoring items in treatment

Similar to those detected with other TNF- inhibitors, refer to the enasip section.

(9) Contraindication

Severely active infection, multiple sclerosis or demyelinating disease, congestive heart failure (the American heart association (NYHA) cardiac Ⅲ or Ⅳ level) and pregnancy.