那他珠单抗(Natalizumab)的用药注意事项

Natalizumab has been launched in many countries/regions and exerts anti-inflammatory effects by inhibiting α4-integrin-mediated leukocyte adhesion and migration.

Precautions before taking Natalizumab

1. Strict evaluation of contraindications

(1) Absolute contraindications: Patients with confirmed or previous history of PML are strictly prohibited from using it. It is contraindicated in patients with a history of hypersensitivity (manifested by urticaria, dyspnea, or even anaphylactic shock) to the product or any of its ingredients.

(2) Risk assessment: Doctors need to discuss the risk factors of PML in detail with patients and weigh the expected efficacy and potential risks.

2. Complete necessary screening and testing

(1). JC virus antibody test: blood test must be performed before medication. A positive result means a significant increase in the risk of PML and is a key basis for decision-making.

(2) Baseline brain MRI (especially for patients with multiple sclerosis): used to establish a reference to distinguish new MS lesions from early signs of PML in the future.

(3) Liver function test: Assess basic liver conditions.

(4) Blood routine: Understand the basic platelet level.

3. Fully inform the doctor about the condition and medication history

Patients should inform the doctor of all health conditions, especially diseases that affect the immune system (such as HIV, lymphoma, history of organ transplantation) and current infections.

The pictures are from public channels (such as the official website of the FDA, the official website of the original drug manufacturer, etc.) and are for reference only.

Precautions during the use of Natalizumab

1. Standardized infusion and observation

(1). Infusion process: The dose is 300mg, which should be infused intravenously for more than 1 hour, and no push injection is allowed. The diluted solution must be used within 4 hours.

(2) Observation after infusion: After the first 12 infusions, patients need to be observed in the medical setting for at least 1 hour to prevent acute allergic reactions. Observation time can be adjusted based on clinical judgment for subsequent infusions.

2. Be alert for signs of serious adverse reactions

(1) Neurological symptoms of PML: Pay close attention to any new or worsening symptoms that last for several days, such as confusion, blurred vision, unilateral limb weakness, clumsiness, and personality changes. Once it occurs, stop taking the drug immediately and seek medical examination (brain MRI, cerebrospinal fluid JC virus DNA detection).

(2) Signs of infection: Be alert for serious infections, such as sudden high fever, severe headache (suggesting encephalitis/meningitis), decreased vision, red and painful eyes (suggesting acute retinal necrosis). Any symptoms of infection should be reported promptly.

(3) Symptoms of liver damage: Pay attention to jaundice (yellowing of skin and eyes), dark urine, abnormal fatigue, nausea and vomiting, and check liver function in time.

(4) Allergic reaction: If urticaria, dyspnea, dizziness, hypotension, etc. occur during or after the infusion, the infusion must be stopped immediately and treated urgently.

(5) Bleeding tendency: Pay attention to signs of thrombocytopenia such as abnormal bruises, epistaxis, gum bleeding, and skin petechiae.

Precautions after taking Natalizumab

1. Continue to monitor the risk of PML

The risk of PML will continue for at least 6 months after stopping the drug. During this period, patients should continue to pay attention to any possible neurological symptoms and report them in time.

2. Pregnancy and lactation considerations

(1) Pregnancy: Medication may cause neonatal thrombocytopenia. If you plan to become pregnant or are pregnant, you should inform your doctor immediately and discuss the pros and cons together.

(2) Breastfeeding: The drug will enter the milk, and the impact on the baby is unknown. The decision should be made after weighing whether to stop the drug or stop breastfeeding.