Soliris

Soliris (eculizumab) is a complement inhibitor given by intravenous (IV) infusion. It is used to treat:

• Paroxysmal nocturnal hemoglobinuria (PNH) in adults, to reduce the breakdown of red blood cells (hemolysis)
• Atypical hemolytic uremic syndrome (aHUS) in adults and children, to block complement-mediated thrombotic microangiopathy (TMA), a condition where small blood clots damage blood vessels and organs such as the kidneys
• Generalized myasthenia gravis (gMG) in adults and children 6 years of age and older who are anti-acetylcholine receptor (AChR) antibody positive
• Neuromyelitis optica spectrum disorder (NMOSD) in adults who are anti-aquaporin-4 (AQP4) antibody positive.

Soliris is not used to treat people with Shiga toxin E. coli-related hemolytic uremic syndrome (STEC-HUS).

Soliris first gained FDA approval on March 16, 2007, for PNH. Further approvals followed for aHUS (2011), gMG in adults (2017), NMOSD (2019), and gMG in children 6 years and older (March 2025).

Two interchangeable biosimilars to Soliris are available, Bkemv (eculizumab-aeeb) and Epysqli (eculizumab-aagh), which may be substituted for Soliris at the pharmacy level. Ultomiris (ravulizumab-cwvz) is a longer-acting C5 inhibitor, also made by Alexion Pharmaceuticals, that is used for PNH, aHUS, gMG, and NMOSD (see How does Ultomiris compare to Soliris for PNH?).

Soliris is a monoclonal antibody that binds tightly to complement protein C5, part of the immune system's complement pathway. This stops C5 from being split into C5a and C5b, which prevents formation of the terminal complement complex (C5b-9), sometimes called the membrane attack complex.

• PNH: Red blood cells lack natural protection against complement, so the terminal complement complex destroys them inside blood vessels. Soliris blocks this breakdown (see How does Soliris work for PNH?).
• aHUS: Soliris blocks the complement-mediated damage that causes TMA.
• gMG and NMOSD: The exact way Soliris works is not known, but it is thought to reduce deposits of the terminal complement complex at the junction between nerves and muscles (gMG) or in response to anti-AQP4 antibodies (NMOSD).

Because Soliris blocks part of the immune system, it increases the risk of certain serious infections, especially meningococcal infections.

In aHUS, 20 of 24 adults and 9 of 11 children who needed dialysis at the start were able to stop dialysis during Soliris treatment. In gMG, Soliris also improved muscle strength on the QMG score (4.6 vs 1.6 points), and response was usually seen by 12 weeks. In NMOSD, Soliris reduced the risk of relapse by 94% compared with placebo and lowered the rate of hospitalizations.

Because of the risk of serious meningococcal infections, Soliris is available only through a restricted program called the Ultomiris and Soliris REMS (Risk Evaluation and Mitigation Strategy). Before you can receive Soliris, your healthcare provider must:

• Enroll in the Ultomiris and Soliris REMS program
• Counsel you about the risk of serious meningococcal infections
• Give you information about the signs and symptoms of serious meningococcal infection
• Make sure that you are vaccinated against serious infections caused by meningococcal bacteria, and that you receive antibiotics if you need to start Soliris right away and you are not up to date on your vaccines
• Give you a Patient Safety Card about your risk of meningococcal infection.

Hospitals, clinics, and pharmacies that dispense Soliris must also be certified in the REMS. More information is available at www.UltSolREMS.com or 1-888-765-4747.

Soliris is given by a healthcare provider as an infusion into a vein (IV infusion). It must not be given as a rapid injection (IV push).

• The infusion is given over 35 minutes in adults and over 1 to 4 hours in children.
• Adults usually receive an infusion weekly for 5 weeks, then every 2 weeks. For children, the schedule depends on body weight.
• Doses should be given on schedule, or within 2 days of the scheduled time.
• You will be monitored for at least 1 hour after each infusion for infusion-related reactions.
• If you have an infusion-related reaction, the infusion may be slowed or stopped. In adults, a slowed infusion should not take longer than 2 hours.

Stopping Soliris

Do not stop receiving Soliris without talking to your healthcare provider.

PNH: your healthcare provider will need to monitor you closely for at least 8 weeks after stopping Soliris. Stopping treatment may cause a breakdown of your red blood cells. Symptoms or problems that can happen due to red blood cell breakdown include:

• Drop in the number of your red blood cells
• Drop in your platelet count
• Confusion
• Kidney problems
• Blood clots
• Difficulty breathing
• Chest pain.

aHUS: your healthcare provider will need to monitor you closely for at least 12 weeks after stopping Soliris for signs of worsening aHUS or problems related to abnormal clotting (thrombotic microangiopathy). Symptoms or problems that can happen with abnormal clotting include:

• Stroke
• Confusion
• Seizure
• Chest pain (angina)
• Difficulty breathing
• Kidney problems
• Swelling in the arms or legs
• A drop in your platelet count.

Do not receive Soliris if you have a serious meningococcal infection when you are starting Soliris treatment.

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

• Have an infection or fever
• Are pregnant or plan to become pregnant
• Are breastfeeding or plan to breastfeed.

You must be vaccinated against meningococcal infection at least 2 weeks before starting Soliris, unless your healthcare provider decides that delaying treatment is riskier. Children also need vaccines against Streptococcus pneumoniae and Hib.

It is not known if Soliris is safe and effective in children with PNH or NMOSD, or in children with gMG under 6 years of age.

Pregnancy

It is not known if Soliris will harm your unborn baby. Data from more than 300 pregnancies with live births after Soliris exposure have not suggested safety concerns, although these data cannot rule out all risks. Untreated PNH and aHUS in pregnancy carry serious risks for both mother and baby, including blood clots, preeclampsia, preterm delivery, and fetal death. Tell your healthcare provider if you are pregnant or plan to become pregnant.

Breastfeeding

It is not known if Soliris passes into your breast milk. Limited published data have not found detectable levels of eculizumab in breast milk. Talk to your healthcare provider about the best way to feed your baby while receiving Soliris.

Common side effects

The most common side effects of Soliris differ depending on the condition being treated:

In children with aHUS, fever, diarrhea, vomiting, stomach pain, cough, and upper respiratory infections were among the most common side effects.

Serious side effects and warnings

Soliris has a Boxed Warning for serious meningococcal infections.

Meningococcal infections. Soliris increases your chance of getting serious meningococcal infections caused by Neisseria meningitidis bacteria. These infections may quickly become life-threatening or cause death if not recognized and treated early. They have occurred in both vaccinated and unvaccinated people.

• You must complete or update your meningococcal vaccines (for serogroups A, C, W, Y, and B) at least 2 weeks before your first dose of Soliris.
• If you have not completed your meningococcal vaccines and Soliris must be started right away, you should receive the required vaccines as soon as possible.
• If you have not been vaccinated and Soliris must be started right away, you should also receive antibiotics to take for as long as your healthcare provider tells you.
• If you had a meningococcal vaccine in the past, you might need additional vaccines before starting Soliris. Your healthcare provider will decide if you need additional meningococcal vaccines.
• Meningococcal vaccines do not prevent all meningococcal infections. Call your healthcare provider or get emergency medical care right away if you get any of these signs and symptoms of a serious meningococcal infection: Fever Fever and a rash Fever with high heart rate Headache with nausea or vomiting Headache and fever Headache with a stiff neck or stiff back Confusion Eyes sensitive to light Muscle aches with flu-like symptoms.

Your healthcare provider will give you a Patient Safety Card about the risk of serious meningococcal infection. Carry it with you at all times during treatment and for 3 months after your last dose of Soliris. Your risk of meningococcal infection may continue for several weeks after your last dose. It is important to show this card to any healthcare provider who treats you. This will help them diagnose and treat you quickly.

Other serious infections. Soliris may also increase the risk of other types of serious infections caused by encapsulated bacteria, including Streptococcus pneumoniae, Haemophilus influenzae, and Neisseria gonorrhoeae.

• If your child is treated with Soliris, your child should receive vaccines against Streptococcus pneumoniae and Haemophilus influenzae type b (Hib).
• Certain people may be at risk of serious infections with gonorrhea. Talk to your healthcare provider about whether you are at risk for gonorrhea infection, about gonorrhea prevention, and regular testing.
• Certain fungal infections (Aspergillus) may also happen if you receive Soliris and have a weak immune system or a low white blood cell count.

Serious infusion-related reactions. Serious infusion-related reactions, including allergic reactions, can happen during your Soliris infusion. Tell your healthcare provider or nurse right away if you get any of these symptoms during your infusion:

• Chest pain
• Trouble breathing or shortness of breath
• Swelling of your face, tongue, or throat
• Feeling faint or passing out.

If you have an infusion-related reaction, your healthcare provider may need to infuse Soliris more slowly or stop the infusion.

Liver problems. Since approval, cases of liver injury with raised liver enzymes and bilirubin have been reported in adults and children with aHUS, usually within 3 to 27 days of starting Soliris. These generally resolved in about 3 weeks.

Worsening of your condition after stopping Soliris. Do not stop receiving Soliris without first talking to your healthcare provider. Stopping treatment may cause serious problems (see Stopping Soliris below).

This is not a complete list of side effects, and others may occur. Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088 or to Alexion Pharmaceuticals at 1-844-259-6783.

Usual adult dose for paroxysmal nocturnal hemoglobinuria (PNH)

• 600 mg by IV infusion weekly for the first 4 weeks, then
• 900 mg for the fifth dose 1 week later, then
• 900 mg every 2 weeks.

Usual adult dose for aHUS, gMG, or NMOSD

• 900 mg by IV infusion weekly for the first 4 weeks, then
• 1,200 mg for the fifth dose 1 week later, then
• 1,200 mg every 2 weeks.

Usual pediatric dose for aHUS (under 18 years) or gMG (6 years and older)

Extra doses with plasma treatments or IVIg

Plasmapheresis, plasma exchange, and fresh frozen plasma infusion remove Soliris from the blood. People with aHUS, gMG, or NMOSD who receive these treatments need a supplemental dose of Soliris (300 mg or 600 mg, depending on the most recent dose). People with gMG who receive regular intravenous immunoglobulin (IVIg) also need a supplemental dose. Your healthcare provider will work out the extra dose and timing.

Do not miss infusions or stop Soliris without talking to your healthcare provider. If you take a blood thinner (anticoagulant), do not stop or change it because you are receiving Soliris, unless your healthcare provider tells you to. The effect of stopping anticoagulants during Soliris treatment has not been studied.

Seek medical care right away if you develop signs of a meningococcal infection, even if you have been vaccinated.

If you miss a Soliris infusion, call your healthcare provider right away. In aHUS, serious clotting problems have happened after a missed dose.

Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements. Keep a list of your medicines and vaccines to show your healthcare provider and pharmacist. Soliris may be affected by:

• Neonatal Fc receptor (FcRn) blockers, such as efgartigimod alfa (Vyvgart, Vyvgart Hytrulo), rozanolixizumab (Rystiggo), or nipocalimab (Imaavy). These medicines may lower Soliris levels in the blood and make it less effective. Your healthcare provider should monitor you closely if you use them together.
• Plasmapheresis, plasma exchange, fresh frozen plasma infusion, or IVIg, which lower Soliris levels and require a supplemental dose.

This is not a complete list of interactions. Other drugs may interact with eculizumab, including prescription and over-the-counter medicines, vitamins, and herbal products.

Injection: 300 mg/30 mL (10 mg/mL) clear, colorless solution in a single-dose vial. Soliris is diluted before infusion.

• Store Soliris vials in the refrigerator at 36°F to 46°F (2°C to 8°C) in the original carton to protect from light.
• Vials may be kept in the original carton at room temperature (no higher than 77°F/25°C) for a single period of up to 3 days.
• Do not freeze. Do not shake.
• Once diluted, Soliris can be stored for up to 24 hours in the refrigerator or at room temperature.

Active ingredient: eculizumab

Inactive ingredients: polysorbate 80 (vegetable origin), sodium chloride, sodium phosphate dibasic, sodium phosphate monobasic, and Water for Injection.