Bonspri, containing the active ingredient Ofatumumab, is a fully human monoclonal antibody targeting CD20. It is primarily used for the treatment of relapsing forms of multiple sclerosis (RMS) and chronic lymphocytic leukemia (CLL). Ofatumumab works by depleting B cells, which play a role in the immune system’s attack on the central nervous system in multiple sclerosis.

Uses

• Relapsing Multiple Sclerosis (RMS): Reduces the frequency of relapses and delays disease progression.

• Chronic Lymphocytic Leukemia (CLL): Used in combination with other medications for certain cases of CLL.

Mechanism of Action

Ofatumumab binds to the CD20 molecule on the surface of B cells, leading to B-cell lysis. This action helps suppress the autoimmune response responsible for nerve damage in multiple sclerosis and eliminates malignant B cells in leukemia.

Dosage

For Multiple Sclerosis:

• Initial dose: 20 mg subcutaneous injection at weeks 0, 1, and 2.

• Maintenance dose: 20 mg once monthly starting at week 4.

For Chronic Lymphocytic Leukemia: Dosage and schedule depend on the treatment regimen.

Side Effects

• Common Side Effects: Injection site reactions, upper respiratory tract infections, and headache.

• Serious Side Effects: Hepatitis B reactivation, progressive multifocal leukoencephalopathy (PML), and serious infections.

Precautions

• Hepatitis B Monitoring: Screen for hepatitis B infection before initiating treatment.

• Immunizations: Avoid live vaccines during and shortly after treatment.

• Infection Risk: Monitor for signs of infection, including fever and persistent cough.

Onset and Duration of Action

• Onset of Action: B-cell depletion occurs rapidly after the first dose.

• Duration of Action: Effects last as long as treatment is continued, with B-cell recovery taking months after discontinuation.

Contraindications

• Active infection.

• Hypersensitivity to Ofatumumab or any of its components.

Storage

• Store in a refrigerator at 2°C to 8°C (36°F to 46°F).

• Do not freeze. Protect from light.