那他珠单抗(Tysabri)的功效与作用

Natalizumab (Tysabri) was originally developed by Biogen (in collaboration with Elan) and was approved for marketing by the US FDA under accelerated review in 2004.

Efficacy and role of natalizumab (Tysabri)

1. Multiple sclerosis (MS)

It is designated as monotherapy for adults with relapsing forms of multiple sclerosis, including clinically isolated syndrome, relapsing-remitting disease, and active secondary progressive disease. Natalizumab increases the risk of progressive multifocal leukoencephalopathy (PML). When initiating and continuing natalizumab therapy, physicians should consider whether the expected benefits of natalizumab are sufficient to offset this risk.

2. Crohn's disease (CD)

Natalizumab is indicated to induce and maintain clinical responses and remissions in adult patients with moderately to severely active Crohn's disease with evidence of inflammation who have an inadequate response to or intolerance to conventional CD therapies and tumor necrosis factor-alpha (TNF-alpha) inhibitors. Natalizumab should not be used in combination with immunosuppressants (eg, 6-mercaptopurine, azathioprine, cyclosporine, or methotrexate) or TNF-α inhibitors.

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.

Natalizumab Medication Guide

1. Multiple Sclerosis (MS)

Only prescribers registered to participate in the MSTOUCH prescription program can prescribe natalizumab for multiple sclerosis. The recommended dose of natalizumab for multiple sclerosis is 300 mg as an intravenous infusion over one hour every four weeks.

2. Crohn's disease (CD)

The recommended dose of natalizumab for Crohn's disease is 300 mg once every four weeks as an intravenous infusion for one hour. Natalizumab should not be used in combination with concomitant immunosuppressants (e.g., 6-mercaptopurine, azathioprine, cyclosporine, or methotrexate) or concomitant TNF-α inhibitors. Aminosalicylates may be continued during natalizumab treatment.

3. Treatment with discontinuation

If patients with Crohn's disease do not experience therapeutic benefit after 12 weeks of induction therapy, natalizumab should be discontinued. For patients with Crohn's disease who are receiving chronic oral corticosteroid therapy when initiating natalizumab, a tapering of the steroid dose should be initiated as soon as a benefit from natalizumab treatment occurs.

If a patient with Crohn's disease cannot discontinue oral corticosteroids within six months of starting natalizumab, natalizumab should be discontinued. In addition to the initial six-month tapering period, prescribers should consider discontinuing natalizumab in patients who require additional steroid use for more than three months in the calendar year to control their Crohn's disease.

4. Dilution instructions

Aseptic techniques must be used when preparing natalizumab solutions for intravenous infusion. Each vial is for single use only. Discard any unused portion.

Natalizumab is a colorless, clear to slightly opalescent solution. Natalizumab vials should be inspected for particulate matter and discoloration prior to dilution and administration. If visible particulates and/or discoloration of the liquid in the vial is observed, the vial should not be used.

To prepare the dilute solution, use a sterile needle and syringe to withdraw 15 mL of natalizumab from the vial. Inject natalizumab into 100 mL of 0.9% sodium chloride injection (USP). No other intravenous diluents should be used to prepare dilute solutions of natalizumab.

Gently invert the natalizumab diluted solution to mix thoroughly without shaking. Visually inspect the solution for particulate matter before dosing. The final dose of the diluted solution should be 2.6 mg/mL.

5. Administration Instructions

Complete infusion of natalizumab 300 mg in 100 mL of 0.9% sodium chloride injection (USP) over approximately one hour (at an infusion rate of approximately 5 mg per minute). Do not give natalizumab as an intravenous push or bolus injection. After the infusion is completed, flush the line with 0.9% sodium chloride injection (USP).

Observe the patient during all infusions. Stop the infusion immediately if any signs or symptoms consistent with a type of hypersensitivity reaction are observed.

After infusion, for the first 12 infusions, observe the patient for one hour after the infusion is completed. For patients who have received 12 infusions without evidence of hypersensitivity, observation after the 13th and subsequent infusions should be based on clinical judgment.

The use of filtering devices during drug administration has not been evaluated. Other drugs should not be injected into the side port of the infusion device or mixed with natalizumab.

Contraindications of Natalizumab

1. Natalizumab is contraindicated in patients who have or have had progressive multifocal leukoencephalopathy (PML).

2. Natalizumab is contraindicated in patients with hypersensitivity reactions to natalizumab. Observed reactions range from hives to anaphylaxis.