Betaseron is used for relapsing forms of multiple sclerosis (MS), including relapsing-remitting multiple sclerosis (RRMS), isolated syndrome, and active secondary progressive disease in adults. Betaseron (interferon beta-1b) helps to reduce the number of flare-ups and clinical symptoms in relapsing forms of multiple sclerosis, but it will not cure MS. Betaseron injection works as it is similar to a protein in the body called interferon, which is involved in inflammation.

Betaseron is given as an injection under the skin every other day.

Betaseron injection received FDA approval on July 23, 1993, and can now be used to treat adults with relapsing forms of multiple sclerosis, including clinically isolated syndrome, relapsing-remitting disease, and active secondary progressive disease, in adults. This includes people who have had their first symptoms of multiple sclerosis and have an MRI consistent with multiple sclerosis.

Betaseron side effects

Common Betaseron side effects may include:

• low white blood cell counts;
• abnormal liver function tests;
• headache, weakness;
• sleep problems (insomnia);
• stomach pain;
• muscle pain, stiffness, or weakness;
• rash;
• flu symptoms; or
• a skin reaction where the medicine was injected.

Serious Betaseron side effects
Allergic reactions Get emergency medical help if you have signs of an allergic reaction to Betaseron injection: hives, difficulty breathing, swelling of your face, lips, tongue, or throat.

Liver problems including liver failure Symptoms of liver problems include yellowing of eyes, itchy skin, nausea or vomiting, feeling very tired, flu-like symptoms, and bruising easily or bleeding problems.

Depression Some patients using interferon medicines have become very depressed or had thoughts of suicide. Report any new or worsening symptoms of depression to your doctor, such as mood or behavior changes, anxiety, trouble sleeping, hallucinations, or if you feel impulsive, hostile, aggressive, depressed, or have thoughts about suicide or hurting yourself.

Other serious side effects Stop using Betaseron injection and call your doctor at once if you have:

• fever, chills, sweating, tiredness, body aches;
• a seizure;
• pain, swelling, redness, or skin changes where an injection was given;
• heart problems – chest tightness, swelling, rapid weight gain, trouble lying flat in bed, feeling short of breath;
• liver problems – nausea, vomiting, itching, easy bruising, unusual bleeding, dark urine, jaundice (yellowing of your skin or eyes); or
• new or worsening symptoms of lupus – joint pain and a skin rash on your cheeks or arms that worsens in sunlight.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects.

Warnings

Betaseron may be harmful to an unborn baby or may cause a miscarriage. Do not use Betaseron if you are pregnant. Tell your doctor if you are pregnant or plan to become pregnant during treatment.

Before using Betaseron, tell your doctor if you are allergic to any drugs, or if you have liver disease, a thyroid disorder, epilepsy or other seizure disorder, a bleeding or blood-clotting disorder, anemia (low red blood cells), or a history of depression or suicidal behavior.

Serious allergic reactions can happen quickly and may happen after your first dose of Betaseron or after you have taken Betaseron many times. Symptoms may include difficulty breathing or swallowing, swelling of the mouth or tongue, rash, itching, or skin bumps.

Some patients using interferon medications have become very depressed or had thoughts of suicide. Stop using Betaseron if you have symptoms of depression (sadness, crying, loss of interest in things you once liked) or if you have any thoughts of hurting yourself.

Interferon beta-1b can harm your liver. Call your doctor at once if you have nausea, vomiting, itching, bruising or bleeding, or yellowing of your skin or eyes.

To be sure Betaseron is not causing harmful effects, your blood and liver function will need to be tested on a regular basis. Your thyroid function may also need to be tested. Do not miss any scheduled appointments.

Before taking this medicine

You should not use Betaseron if you are allergic to interferon beta, albumin, or mannitol.

To make sure Betaseron is safe for you, tell your doctor if you have:

• liver disease;
• heart problems;
• a seizure;
• depression, anxiety, or sleep problems;
• a bleeding or blood-clotting disorder;
• low white blood cell (WBC) counts;
• anemia (lack of red blood cells); or
• an allergy to latex.

Tell your doctor if you are pregnant or breastfeeding.

How should I use Betaseron?

Use Betaseron exactly as prescribed by your doctor. Follow all directions on your prescription label and read all medication guides or instruction sheets. Your doctor may occasionally change your dose.

Betaseron is injected under the skin, usually every other day. A healthcare provider may teach you how to properly use the medication by yourself.

Read and carefully follow any Instructions for Use provided with your medicine. Ask your doctor or pharmacist if you don’t understand all instructions.

Prepare an injection only when you are ready to give it. Do not use if the medicine looks cloudy, has changed colors, or has particles in it. Call your pharmacist for new medicine.

Your healthcare provider will show you where on your body to inject Betaseron. Use a different place each time you give an injection. Do not inject into the same place two times in a row.

You will need frequent medical tests.

Store unmixed Betaseron and the diluent at cool room temperature away from moisture and heat.

After mixing, store the medicine in the refrigerator and use within 3 hours. Do not freeze.

Each single-use vial (bottle) or prefilled syringe is for one use only. Throw it away after one use, even if there is still medicine left inside. Throw away any Betaseron that is not used within 3 months.

Use a needle and syringe only once and then place them in a puncture-proof “sharps” container. Follow state or local laws about how to dispose of this container. Keep it out of the reach of children and pets.

Betaseron Dosing information

Usual Betaseron Adult Dose for Multiple Sclerosis:

Initial dose: 0.0625 mg subcutaneously every other day, and increased (in 25% increments) every 2 weeks, over a 6 week period, to maintenance dose
Maintenance dose: 0.25 mg subcutaneously every other day

Schedule for dose titration:
Weeks 1 and 2: 0.0625 mg subcutaneously every other day (25% of recommended dose)
Weeks 3 and 4: 0.125 mg subcutaneously every other day (50% of recommended dose)
Weeks 5 and 6: 0.1875 mg subcutaneously every other day (75% of recommended dose)
Week 7 and beyond: 0.25 mg subcutaneously every other day (100% of recommended dose)

Betaseron Use: For the treatment of relapsing forms of multiple sclerosis to reduce the frequency of clinical exacerbations. Patients with multiple sclerosis in whom efficacy has been demonstrated include patients who have experienced a first clinical episode and have MRI features consistent with multiple sclerosis.

What happens if I miss a dose?

Use the missed dose as soon as you remember. Then wait at least 48 hours (2 days) before using another injection, and restart your dosing schedule at that time. Do not use more than one injection every 48 hours.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line .

What should I avoid while using Betaseron?

Avoid injecting this medicine into skin that is sore, red, or infected.

Avoid drinking alcohol. It may increase your risk of liver problems.

What other drugs will affect Betaseron?

Other drugs may interact with interferon beta-1b, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell your doctor about all your current medicines and any medicine you start or stop using.

Ingredients

Active ingredient: interferon beta-1b

Inactive ingredients: albumin (human), mannitol Diluent contains sodium chloride solution.

Company

Manufactured for: Bayer HealthCare Pharmaceuticals Inc. Whippany, NJ 07981

Betaseron Biosimilars

Biosimilar and interchangeable products are biological products that are highly similar to and have no clinically meaningful differences from the reference product.

Reference products

These are biological products that have already been approved by the FDA, against which biosimilar products are compared. There is 1 for Betaseron.Betaseron (interferon beta-1b) – Bayer HealthCare Pharmaceuticals Inc.

Benlysta is used to treat active systemic lupus erythematosus (SLE) or lupus nephritis (LN) in people 5 years and older, who weigh at least 15 kg (33 lb), and are receiving standard therapy. Benlysta is a monoclonal antibody given by injection every 2 to 4 weeks. Clinical trials show that when Benlysta is combined with other lupus medicines, it reduces disease activity more effectively than other medicines alone.

• Benlysta is not recommended for severe active central nervous system lupus because it has not been studied in this population.

Benlysta (belimumab) first gained FDA approval on March 9, 2011, and was the first lupus treatment specifically designed to target the underlying autoimmune process that causes lupus. 

How Does Benlysta Work? Mechanism of Action

Benlysta is a BLyS-specific inhibitor that works by blocking the BLyS protein that keeps harmful B-cells alive and active. This reduces B-cell survival and decreases autoantibody production, reducing the overactive immune response behind lupus flares and symptoms such as fatigue and joint pain.

Unlike broad immunosuppressants that affect your entire immune system, Benlysta specifically targets the cells and proteins involved in lupus.

Benlysta (belimumab) belongs to the drug class called B-lymphocyte stimulator (BLyS)-specific inhibitors.

What is the cost of Benlysta?

The list price for Benlysta injection is just over $1,200 per single dose (sold in a 4-pack for just over $4,800), while Benlysta infusion pricing varies based on patient weight.

Most insurance plans cover Benlysta, with over 95% of lupus patients nationwide having coverage.

Eligible commercially insured patients may qualify for the Benlysta Copay program, which can reduce out-of-pocket costs to as little as $0, with up to $9,450 in annual assistance. 

Benlysta Side Effects

Common Side Effects

The most common side effects of Benlysta are:

• Nausea
• Diarrhea
• Fever
• Stuffy or runny nose and sore throat (nasopharyngitis)
• Persistent cough (bronchitis)
• Trouble sleeping (insomnia)
• Leg or arm pain
• Depression
• Headache (migraine)
• Pain, redness, itching, or swelling at the site of the injection (when given subcutaneously).

Serious Side Effects

Benlysta can cause serious side effects, including:

• Progressive multifocal leukoencephalopathy (PML). This is a serious and life-threatening brain infection. Your chance of getting PML may be higher if you are treated with medicines that weaken your immune system, including Benlysta. PML can result in death or severe disability. If you notice any new or worsening medical problems such as those below, tell your healthcare provider right away:
  • memory loss
  • trouble thinking
  • dizziness or loss of balance
  • difficulty talking or walking
  • loss of vision.
• Cancer. Benlysta may reduce the activity of your immune system. Medicines that affect the immune system may increase your risk of certain cancers.

See also Warnings below.

These are not all the possible side effects of Benlysta. Call your doctor for medical advice about side effects.

Warnings

Immunosuppressive agents, including Benlysta, can cause serious side effects. Some of these side effects may cause death. 

Benlysta may increase the risk of infection, some of which may be serious, leading to hospitalization or death. Benlysta should be used with caution in patients with severe or chronic infections. Your healthcare provider may withhold your treatment with Benlysta if you develop a new infection during treatment. Tell your healthcare provider right away if you have any of the following symptoms of an infection:

• Fever
• Urinating often
• Chills
• Coughing up mucus
• Pain or burning with urination
• Warm, red, or painful skin or sores on your body.

Should not be given to people with a history of serious hypersensitivity reactions to Benlysta, belimumab, or any of the ingredients in the formulation. Serious hypersensitivity reactions, including anaphylaxis and infusion-related reactions, can happen on the day of, or in the days after, receiving Benlysta and may cause death. Your healthcare provider will watch you closely while you are receiving Benlysta intravenously and after your infusion for signs of a reaction. Allergic reactions can sometimes be delayed. Tell your healthcare provider right away if you have any of the following symptoms of an allergic reaction following a benlysta infusion:

• Itching
• Low blood pressure
• Swelling of the face, lips, mouth, tongue, or throat
• Dizziness or fainting
• Headache
• Trouble breathing
• Nausea
• Anxiousness
• Skin rash.

Symptoms of mental health problems, including suicidal thoughts and actions, can occur with Benlysta. Tell your healthcare provider right away if you have any of the following symptoms:

• Thoughts of suicide or dying
• New or worse depression
• Attempt to commit suicide
• Acting on dangerous impulses
• Trouble sleeping (insomnia)
• Other unusual changes in your behavior or mood
• New or worse anxiety
• Thoughts of hurting yourself or others.

Before Receiving Benlysta

Absolute Contraindications

Do not receive Benlysta if you have previously had an anaphylactic reaction to Benlysta.

Caution Needed

Before you receive Benlysta, tell your healthcare provider about all of your medical conditions, including if you:

• Think you have an infection or have infections that keep coming back. You should not receive Benlysta if you have an infection unless your healthcare provider tells you to.
• Have or have had mental health problems such as depression or thoughts of suicide
• Have recently received a vaccination, or if you think you may need a vaccination. If you are receiving Benlysta, you should not receive live vaccines
• Are allergic to other medicines
• Are receiving other biologic medicines or monoclonal antibodies
• Have or have had any type of cancer
• Are pregnant or plan to become pregnant
• Are breastfeeding or plan to breastfeed.

Pregnancy

It is not known if Benlysta will harm an unborn baby. You should talk to your healthcare provider about whether to prevent pregnancy while on Benlysta.

If you choose to prevent pregnancy, you should use an effective method of birth control while receiving Benlysta and for at least 4 months after the final dose of Benlysta.

• Tell your healthcare provider right away if you become pregnant during your treatment with Benlysta or if you think you may be pregnant.
• If you become pregnant while receiving Benlysta, talk to your healthcare provider about enrolling in the Benlysta Pregnancy Registry.
• The purpose of this registry is to collect information about the health of you and your baby.

Breastfeeding

It is not known if Benlysta passes into your breast milk. You and your healthcare provider should talk about whether or not you should receive Benlysta and breastfeed.

How will I receive Benlysta?

Benlysta is available as IV infusions at a healthcare facility every 2-4 weeks, or subcutaneous injections for home use weekly or fortnightly.

• Both are equally effective; your doctor will recommend the best option.

How is a Benlysta infusion given?

You will be given Benlysta by a healthcare provider through a needle placed in a vein (IV infusion).

• It takes about 1 hour to give you the full dose of Benlysta.
• Your healthcare provider will tell you how often you should receive Benlysta.
• Your healthcare provider may give you medicines before you receive Benlysta to help reduce your chance of having a reaction. A healthcare provider will watch you closely while you are receiving Benlysta and after your infusion for signs of a reaction. A healthcare provider will review the signs and symptoms of possible allergic reactions that could happen after your infusion.

How is a Benlysta injection given?

Your healthcare provider will tell you how often and how much of Benlysta you should use. Use Benlysta exactly as your healthcare provider tells you to.

• Read the Instructions for Use that comes with your medicine for instructions about the right way to give Benlysta injections at home.
• Benlysta may be prescribed as a single-dose autoinjector or as a single-dose prefilled syringe.
  • The single-dose autoinjector is for use in adults and children 5 years of age and older.
  • The single-dose prefilled syringe is for use in adults 18 years of age and older.
  • For children under 10 years of age, Benlysta must be given by a healthcare provider or a trained caregiver.
• Remove from the refrigerator and allow it to reach room temperature for 30 minutes.
• Benlysta is injected under the skin (subcutaneously) of your stomach (abdomen) or thigh.
• Rotate injection sites
• Avoid skin that is bruised, tender, red, or hard.
• Use Benlysta on the same day each week or the same day every 2 weeks, as your healthcare provider tells you.

Before you use Benlysta, your healthcare provider will show you or your caregiver how to give the injections and review the signs and symptoms of possible allergic reactions.

What Happens if I Miss a Dose?

If you miss your subcutaneous dose of Benlysta on your planned day, inject a dose as soon as you remember. Then, inject your next dose at your regularly scheduled time or continue dosing based on the new day injected. In case you are not sure when to inject Benlysta, call your healthcare provider.

Call your doctor for instructions if you miss an appointment for your IV Benlysta infusion.

Dosing Information

Intravenous Dosing of Benlysta for Active SLE or Lupus Nephritis

• 10 mg/kg at 2-week intervals for the first 3 doses and at 4-week intervals thereafter.
• Administer over 1 hour.
• Consider prophylactic premedications for infusion reactions and hypersensitivity reactions.

Subcutaneous Dosing of Benlysta for Active SLE or Lupus Nephritis

Active SLE:

• Adults: 200 mg once weekly
• Pediatric patients (≥40 kg): 200 mg once weekly
• Pediatric patients (15 kg to <40 kg): 200 mg every 2 weeks.

Active Lupus Nephritis:

• Adults: 400 mg once weekly for 4 doses, then 200 mg once weekly
• Pediatric patients (≥40 kg): 400 mg once weekly for 4 doses, then 200 mg once weekly
• Pediatric patients (15 kg to <40 kg): 200 mg once weekly for 4 doses, then 200 mg every 2 weeks.

Note: The 400 mg dose requires two 200 mg injections. Prefilled syringes have not been studied in children under 18 years.

How Long Until Benlysta Works?

Most patients improve within 2-6 months, though responses vary:

• Some notice reduced fatigue and joint pain as early as 8 weeks
• Most begin seeing improvements in lupus symptoms within 2-6 months
• Full benefits may take up to 12 months to develop

Continue treatment as prescribed, even without immediate results, because Benlysta works gradually to suppress your overactive immune response.

What to Avoid While Taking Benlysta

Live Vaccines

Do not receive live vaccines while taking Benlysta, as they may not work properly and could cause infection. Live vaccines include measles, mumps, rubella (MMR), rotavirus, typhoid, yellow fever, chickenpox, shingles, and the nasal flu vaccine. Inactivated vaccines like the flu injection are generally safe and recommended. Always discuss vaccination plans with your healthcare provider.

Sick Contacts

Avoid close contact with people who are sick or have infections, as Benlysta may weaken your immune system.

Drug Interactions

Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements. Especially tell your healthcare provider if you take:

• Other biologics, such as rituximab. Research does not support using Benlysta with other biologics due to increased risk of serious infections and reactions.

Know the medicines you take. Keep a list of your medicines with you to show to your healthcare provider and
pharmacist when you get a new medicine.

Benlysta J Code

Benlysta J code is J0490 (Injection, belimumab, 10 mg).

Storage Instructions

Store autoinjectors and prefilled syringes at 36°F to 46°F (2°C to 8°C) until use and keep in their original carton to protect from light until use.

• Do not freeze
• Do not shake
• Avoid exposure to heat

Do not use Benlysta if it has been left out of the refrigerator for more than 12 hours.

Benlysta Ingredients

Active ingredient: belimumab

Inactive ingredients (IV): citric acid, polysorbate 80, sodium citrate, sucrose

Inactive ingredients (SC): L-arginine hydrochloride, L-histidine, L-histidine monohydrochloride, polysorbate 80, sodium chloride

Available as:

• Intravenous (IV): Single-dose vial: 120 mg or 400 mg lyophilized powder for reconstitution
• Subcutaneous (SC): Prefilled syringe: 200 mg/mL (adults 18+) and autoinjector: 200 mg/mL (ages 5+)

Manufacturer

Benlysta is made by GlaxoSmithKline LLC, Philadelphia, PA 19104.

Frequently Asked Questions

Is Benlysta a chemotherapy drug?

No. Benlysta is a targeted biologic therapy that specifically blocks the BLyS protein involved in lupus. Unlike chemotherapy drugs that kill rapidly dividing cells throughout the body, Benlysta selectively reduces overactive B-cells without the widespread cellular damage associated with chemotherapy.

Can I travel while taking Benlysta?

Yes, you can travel while receiving Benlysta, but you will need to plan ahead. 

• Subcutaneous Benlysta injections:
  • Bring enough medication plus extra for delays
  • Pack in carry-on luggage with a cooling pack (not frozen)
  • Bring a prescription and a doctor’s letter
  • Research medication import requirements for international destinations.
• Intravenous Benlysta Infusions:
  • Coordinate with a healthcare provider to find infusion centers at your destination
  • Consider adjusting the dosing schedule around travel dates.

Will Benlysta cure my lupus?

No, Benlysta will not cure Lupus. However, Benlysta can significantly help manage lupus by reducing disease activity, decreasing frequency and severity of flares, improving symptoms like fatigue and joint pain, potentially slowing organ damage, and improving quality of life.

Can I drink alcohol while taking Benlysta?

There are no specific restrictions on alcohol with Benlysta. However, other lupus medications (like methotrexate or NSAIDs) that you may be taking may interact with alcohol. Alcohol can also worsen lupus symptoms such as fatigue and depression and impair immune function, increasing infection risk.

Talk to your healthcare provider about drinking alcohol with Benlysta. 

Benlysta Biosimilars

Biosimilar and interchangeable products are biological products that are highly similar to and have no clinically meaningful differences from the reference product.

Reference products

These are biological products that have already been approved by the FDA, against which biosimilar products are compared. There is 1 for Benlysta.Benlysta (belimumab) – GlaxoSmithKline LLC

What is azathioprine?

Azathioprine weakens your body’s immune system, to help keep it from “rejecting” a transplanted organ such as a kidney. Organ rejection happens when the immune system treats the new organ as an invader and attacks it.

Azathioprine is used to prevent your body from rejecting a transplanted kidney. Azathioprine is also used to treat symptoms of rheumatoid arthritis.

Azathioprine may also be used for purposes not listed in this medication guide.

Azathioprine side effects

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Azathioprine may cause a serious brain infection that can lead to disability or death. Call your doctor right away if you have problems with speech, thought, vision, or muscle movement. These symptoms may start gradually and get worse quickly.

Stop using azathioprine and call your doctor right away if you have any of these symptoms of lymphoma:

• fever, swollen glands, body aches, night sweats, not feeling well;
• pale skin, rash, easy bruising or bleeding;
• cold hands and feet, feeling light-headed or short of breath;
• pain in your upper stomach that may spread to your shoulder; or
• feeling full after eating only a small amount, weight loss.

Also call your doctor at once if you have:

• signs of infection (fever, chills, weakness, flu symptoms, sore throat, cough, pain or burning when you urinate);
• severe nausea, vomiting, or diarrhea;
• easy bruising, unusual bleeding;
• rapid heartbeats, shortness of breath;
• pale skin, cold hands and feet; or
• dark urine, jaundice (yellowing of the skin or eyes).

Common side effects of azathioprine may include:

• nausea, diarrhea, stomach pain;
• hair loss; or
• skin rash.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects.

Warnings

Azathioprine may cause a rare type of lymphoma (cancer) of the liver, spleen, and bone marrow that can be fatal. This has occurred mainly in teenagers and young men with Crohn’s disease or ulcerative colitis.

Before taking this medicine

You should not take azathioprine if you are allergic to azathioprine.

You should not use azathioprine to treat rheumatoid arthritis if you are pregnant. This medicine can harm an unborn baby. Use effective birth control to prevent pregnancy while using this medicine.

Azathioprine may cause a rare type of lymphoma (cancer) of the liver, spleen, and bone marrow that can be fatal. This has occurred mainly in teenagers and young men with Crohn’s disease or ulcerative colitis. However, anyone with an inflammatory autoimmune disorder may have a higher risk of lymphoma. Talk with your doctor about your own risk.

While taking azathioprine, you may have a higher risk of developing skin cancer. Ask your doctor about skin symptoms to watch for.

Tell your doctor if you have ever had:

• kidney disease, or a kidney transplant (if you are using azathioprine for rheumatoid arthritis);
• any type of viral, bacterial, or fungal infection;
• liver disease; or
• chemotherapy with medications like cyclophosphamide, chlorambucil, melphalan, busulfan, and others.

You should not breast-feed while you are using azathioprine.

How should I take azathioprine?

Your doctor will perform blood tests to make sure you do not have conditions that would prevent you from safely using azathioprine.

Follow all directions on your prescription label and read all medication guides or instruction sheets. Your doctor may occasionally change your dose. Use the medicine exactly as directed.

When given for kidney transplant, azathioprine is usually given right before or on the day of transplant. For rheumatoid arthritis, azathioprine is taken on a daily basis.

It may take up to 8 weeks before your symptoms improve. Keep using azathioprine as directed and tell your doctor if your symptoms have not improved after 12 weeks of use.

Take with food if azathioprine upsets your stomach.

You may not be able to continue taking other arthritis medications together with azathioprine. Do not change your dose or dosing schedule without your doctor’s advice.

Azathioprine affects your immune system. You may get infections more easily, even serious or fatal infections. Your doctor will need to examine you on a regular basis.

Store at room temperature away from moisture, heat, and light. Keep the bottle tightly closed when not in use.

What happens if I miss a dose?

Take the medicine as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not take two doses at one time.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line .

What should I avoid while taking azathioprine?

Avoid sunlight or tanning beds. Azathioprine can increase your risk of developing skin cancer. Wear protective clothing and use sunscreen (SPF 30 or higher) when you are outdoors.

Avoid being near people who are sick or have infections. Tell your doctor at once if you develop signs of infection.