Arzerra (ofatumumab) is a prescription drug that’s used to treat chronic lymphocytic leukemia. The drug comes as a liquid solution for infusion by a healthcare professional. You’ll receive Arzerra on a schedule determined by your doctor.

Arzerra is used in adults to treat chronic lymphocytic leukemia (CLL). It’s used for:

  • CLL that hasn’t been treated previously in people who can’t be treated with a drug called fludarabine (Fludara). For this use, Arzerra is used in combination with a chemotherapy drug called chlorambucil (Leukeran).
  • CLL that has relapsed (come back). For this use, Arzerra is used with the chemotherapy drugs fludarabine and cyclophosphamide.
  • Long-term treatment of progressive or recurrent* CLL in people who’ve previously had a partial or complete response** to at least two types of therapy.
  • It’s also used for CLL that has not improved after treatment with fludarabine and alemtuzumab (Lemtrada).

The active ingredient in Arzerra is ofatumumab. (An active ingredient is what makes a drug work.) Arzerra belongs to a group of drugs called monoclonal antibodies. It’s a biologic drug, which means it’s made from living cells.

This article describes the dosages of Arzerra, as well as its strengths and how it’s given. To learn more about Arzerra, see this in-depth article.

* Progressive means the cancer is getting worse. Recurrent means the cancer has returned.
** A complete response to treatment is when tests show no more cancer in your blood. A partial response is when the level of cancer has decreased by 50% or more.

This section describes the usual dosages of Arzerra. Keep reading to learn more.

What is Arzerra’s form?

Arzerra is available as a liquid solution that’s given as an intravenous (IV) infusion by a healthcare professional in a clinic or hospital. An infusion is a slow injection into your vein over a period of time.

What strength does Arzerra come in?

Arzerra comes in two strengths:

  • 100 milligrams (mg) per 5 milliliters (mL)
  • 1,000 mg per 50 mL

What are the usual dosages of Arzerra?

Your doctor will likely start you on a low dosage of Arzerra and adjust the dosage over time until you reach the amount that’s right for you. They’ll ultimately prescribe the lowest dosage that provides the desired effect.

The information below describes dosages that are commonly used or recommended. Your doctor will determine the best dosage to fit your needs.

Dosage for chronic lymphocytic leukemia (CLL)

The typical Arzerra dosage for adults with CLL depends on several factors. These include the type of CLL being treated, whether you’ve had treatment before, and whether you can take certain types of drugs. The table below describes the dosage for all four types of Arzerra treatment.

Arzerra dosage for first-time treatment of CLL

If you’ve never been treated for CLL before, Arzerra is given in combination with chlorambucil (Leukeran) in 28-day dosage cycles. (Your doctor will tell you the dosage needed for chlorambucil.)

CyclesArzerra infusion dose
Cycle 1, day 1300 mg given over 4–5 hours
Cycle 1, day 8 (1 week later)1,000 mg given over about 4 hours
Cycle 2, day 1, and continued treatment in 28-day cycles with a minimum of 3 cycles and a maximum of 12 cycles1,000 mg given over about 4 hours

Cycle 1: You’ll receive two doses of Arzerra.

On day 1 of treatment, you’ll receive 300 mg of Arzerra by infusion over 4–5 hours. Then on day 8, you’ll receive 1,000 mg on day 1 of subsequent 28-day cycles.

Cycle 2 and following cycles: You’ll receive 1,000 mg of Arzerra over about 4 hours on day 1 of a 28-day treatment cycle. You’ll receive this dosage for at least three 28-day cycles and up to 12 cycles, depending on how your body responds to treatment.

Dosage for relapsed CLL

To treat CLL that has relapsed (come back), Arzerra is given in combination with the drugs fludarabine and cyclophosphamide. (Your doctor will tell you the dosage needed for fludarabine and cyclophosphamide.)

ScheduleArzerra infusion dose
Cycle 1, day 1300 mg given over 4–5 hours
Cycle 1, day 8 (1 week later)1,000 mg given over about 4 hours
Cycle 2, day 1, and continued treatment in 28-day cycles with a maximum of 6 cycles1,000 mg given over about 4 hours

Cycle 1: You’ll receive two doses of Arzerra. On day 1 of treatment, you’ll receive 300 mg of Arzerra by infusion over 4 to 5 hours. On day 8, you’ll receive 1,000 mg on day 1 of subsequent 28-day cycles.

Cycle 2 and following cycles: You’ll receive 1,000 mg of Arzerra by infusion over about 4 hours on day 1 of a 28-day treatment cycle. You’ll receive this dosage for up to 6 cycles, depending on how your body responds to treatment.

Dosage for long-term treatment of CLL that has responded to previous treatment

Arzerra is also used for long-term treatment of recurrent or progressive CLL that has been treated with at least two other types of therapy. For this use, you’ll receive Arzerra without other medications.

ScheduleArzerra infusion dose
Day 1300 mg given over 4–5 hours
Day 8 (1 week later)1,000 mg given over about 4 hours
7 weeks later, and then every 8 weeks for a maximum of 2 years1,000 mg given over about 4 hours

On day 1 of treatment, you’ll receive 300 mg of Arzerra by infusion over 4–5 hours. Then on day 8 (1 week later), you’ll receive Arzerra 1,000 mg over about 4 hours.

Seven weeks later, you’ll receive 1,000 mg of Arzerra by infusion over about 4 hours. After that, every 8 weeks you’ll receive a 1,000-mg dose of Arzerra over about 4 hours, for a maximum of 2 years.

Dosage for CLL that’s stopped responding to certain treatments

To treat CLL that’s stopped responding to the drugs fludarabine and alemtuzumab, you’ll receive 12 total doses of Arzerra on a dosing schedule.

ScheduleArzerra infusion dose
Day 1300 mg given over about 7 hours
Day 8 (1 week later), and then doses once per week for 6 more doses2,000 mg given over about 7 hours
4 weeks later, and then doses once every 4 weeks for 3 more doses2,000 mg given over about 4 hours

On day 1 of treatment, you’ll receive 300 mg of Arzerra by infusion over about 7 hours. Then starting on day 8, you’ll receive 2,000 mg of Arzerra once per week for 7 doses. After this, you’ll receive Arzerra once every 4 weeks for 4 doses.

Is Arzerra used long term?

How long you’ll receive treatment with Arzerra depends on factors such as the type of CLL being treated. You’ll receive Arzerra treatment on a dosing schedule that your doctor will determine.

You’ll receive Arzerra:

  • for up to 12 months for first-time treatment of CLL
  • for up to 6 months for CLL that’s relapsed (returned)
  • for up to 2 years as an extended treatment for recurrent or progressive CLL
  • for up to 6 months for CLL that hasn’t responded to other types of treatment

If you have questions about how long you’ll receive treatment with Arzerra, talk with your doctor.

Dosage adjustments

Your doctor may adjust your dosage of Arzerra if you have certain infusion-related side effects of the medication. If you have questions about dosage adjustments for Arzerra, talk with your doctor.

The dosage of Arzerra you’re prescribed may depend on several factors. These include:

  • the type and severity of CLL you’re using the drug to treat
  • your response to treatment
  • side effects you may experience
  • other medications you may be taking

Arzerra is available as a liquid solution that’s given as an intravenous (IV) infusion. An infusion is an injection into your vein over a period of time. You’ll receive infusions at a hospital or a clinic. Your doctor will monitor you closely while you receive doses of Arzerra.

For your first dose of Arzerra for first-time treatment of CLL, CLL that’s relapsed (returned), or extended treatment for recurrent or progressive CLL, the infusion may take up to 4–5 hours. After this, it may take less time to receive doses of Arzerra.

For your first and second doses of Arzerra for CLL that hasn’t responded to other types of treatment, the infusion may take up to 7 hours. After this, it may take less time to receive doses of Arzerra.

Your doctor may give doses of Arzerra with certain medications to prevent infusion-related reactions. Examples of these medications include:

Examples of infusion-related reactions include:

Your doctor may slow, pause, or stop Arzerra treatment if you have infusion reactions. If you have serious or life-threatening infusion reactions, your doctor will stop treatment with Arzerra and discuss safer treatment options with you.

If you miss an appointment to receive a dose of Arzerra, call your doctor’s office as soon as possible to reschedule. They’ll schedule a time for you to receive the missed dose and adjust your dosing schedule if needed.

If you need help remembering your appointments, try downloading a reminder app on your phone.

Below are answers to some commonly asked questions about Arzerra’s dosage.

Is Arzerra’s dosage similar to the dosage of Copiktra?

No. Arzerra (ofatumumab) and Copiktra (duvelisib) are both used to treat CLL that’s relapsed or hasn’t responded to certain other treatments. However, their forms and dosages are different.

Arzerra comes as a liquid solution that’s given via intravenous (IV) infusion by a healthcare professional in a hospital or clinic. Copiktra, on the other hand, comes as oral capsules.

How often Arzerra is given depends on factors such as the reason for treatment of CLL. After the first two doses, Arzerra is typically given once per month or less frequently over several months. Copiktra is taken twice per day.

To learn more about how these drugs compare, talk with your doctor.

How long does it take for Arzerra to start working?

Arzerra starts to work after your first dose. Because of how the drug works, you likely won’t feel the drug working in your body. But your doctor will do regular tests during treatment to check whether Arzerra is working to treat your condition.

If you have other questions about what to expect from your Arzerra treatment, talk with your doctor.

The sections above describe the usual dosages provided by Arzerra’s manufacturer. If your doctor recommends this drug, they’ll prescribe the dosage that’s right for you.

Talk with your doctor if you have questions or concerns about your current dosage.

Here are some examples of questions you may want to ask your doctor:

  • Will you lower my dosage if I have side effects from Arzerra?
  • Would I need to continue my Arzerra dosage for longer than 2 years for extended treatment of CLL?
  • How does the dosage of Arzerra compare with the dosage of Gazyva (obinutuzumab)?

To learn more about Arzerra, see these articles:

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Disclaimer: Healthline has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.