How it is administered

Glofitamab is given as an intravenous (IV) infusion, which means it is administered directly into your vein by a healthcare professional. The medication is supplied in single-dose vials and is diluted before being infused.

Treatment starts with a single dose of another medication called obinutuzumab, followed by a step-up dosing schedule for glofitamab. The dosing schedule is as follows:

• Cycle 1, Day 1: Obinutuzumab 1,000 mg IV
• Cycle 1, Day 8: Glofitamab 2.5 mg IV (step-up dose 1)
• Cycle 1, Day 15: Glofitamab 10 mg IV (step-up dose 2)
• Cycle 2 and onward (up to 12 cycles): Glofitamab 30 mg IV every 21 days

Patients are usually hospitalized during and for 24 hours after the first step-up doses to monitor for side effects.

How it works

Glofitamab is a bispecific antibody that targets both CD20, a protein found on the surface of B cells (a type of white blood cell involved in many blood cancers), and CD3, a protein on T cells (another type of immune cell). By binding to both CD20 and CD3, glofitamab brings T cells into close proximity with B cells, including cancerous B cells.

This dual binding activates the T cells, causing them to attack and destroy the CD20-expressing B cells. This mechanism helps the immune system target and kill lymphoma cells. In clinical studies, glofitamab has shown anti-tumor activity in patients with diffuse large B-cell lymphoma (DLBCL) and large B-cell lymphoma (LBCL) arising from follicular lymphoma.

The medication can cause a rapid decrease in B cell counts and a temporary increase in cytokines (immune signaling molecules), which is part of its intended effect but also contributes to some of its side effects.

Who Should take it

Glofitamab is indicated for adults with relapsed or refractory diffuse large B-cell lymphoma (DLBCL), not otherwise specified, or large B-cell lymphoma (LBCL) arising from follicular lymphoma, who have already received two or more lines of systemic therapy.

This means it is used when the lymphoma has not responded to previous treatments or has come back after treatment. It is generally reserved for patients who have limited options due to the aggressive or resistant nature of their disease. Your healthcare team will determine if glofitamab is suitable for you based on your diagnosis, prior treatments, and overall health.

Who should not take it

There are no absolute contraindications listed for glofitamab, but it should not be given to patients with active infections. Caution is also advised in patients with a history of severe reactions to similar medications or those with certain medical conditions that could increase the risk of side effects.

Women who are pregnant or may become pregnant should not take glofitamab, as it may cause harm to an unborn baby. Women of reproductive potential should use effective contraception during treatment and for at least one month after the last dose. Breastfeeding is not recommended during treatment and for one month after the last dose.

Commonly used with

Glofitamab is always started after pretreatment with obinutuzumab, which helps deplete B cells and may reduce the risk of certain side effects. Patients may also receive premedications such as acetaminophen, antihistamines, and corticosteroids to help prevent infusion-related reactions and cytokine release syndrome.

Other supportive medications, such as antivirals, antibiotics, or drugs to prevent tumor lysis syndrome, may be used as needed based on your risk factors and doctor's recommendations.

Commonly tested with

Glofitamab has been tested in combination with obinutuzumab as part of its approved treatment regimen for relapsed or refractory large B-cell lymphomas. Clinical trials have also evaluated its use in patients who have previously received other therapies, including CAR-T cell therapy and autologous stem cell transplantation.

Your healthcare team may monitor your response to treatment with blood tests and imaging studies, and may adjust supportive medications as needed to manage side effects.