Ocrevus (ocrelizumab) is a targeted biologic and immunosuppressant used to treat multiple sclerosis (MS). It works by targeting and depleting CD20-positive B-cells, which are believed to be involved in the inflammation and nerve damage associated with MS. Because its mechanism of action involves suppressing the immune system, it is crucial to understand its potential interactions with other medications, therapies, and vaccines. Incorrectly combining Ocrevus with other treatments can lead to an increased risk of infections, reduced vaccine efficacy, or other serious side effects.
Medications That Interact with Ocrevus
Several categories of medications require careful consideration before or during Ocrevus treatment due to their effects on the immune system.
Other Immunosuppressive and Immune-Modulating Therapies
Perhaps the most significant interaction involves the concurrent use of other immunosuppressants. Combining Ocrevus with other therapies that also weaken the immune system can create an additive effect, profoundly increasing the risk of serious, and sometimes life-threatening, infections. This is why doctors typically avoid prescribing Ocrevus with other immunosuppressants used for MS, or require a washout period when switching therapies.
Corticosteroids
Corticosteroids, such as prednisone and methylprednisolone, are often used to manage inflammation in MS. While a short, high-dose course may be given as a pre-medication before an Ocrevus infusion to minimize infusion reactions, long-term or high-dose use with Ocrevus can heighten the risk of infection. Your doctor will carefully weigh the risks and benefits of using these medications together.
Vaccines
Interactions with vaccines are a major consideration for anyone on Ocrevus, and the type of vaccine—live or non-live—is key.
Live or Live-Attenuated Vaccines: These vaccines, which contain a weakened form of the virus or bacteria, are not recommended during Ocrevus treatment or until B-cells have fully recovered. The suppressed immune system may not be able to fight off the weakened pathogen, potentially causing the disease it is meant to prevent. Examples include vaccines for measles, mumps, rubella (MMR), chickenpox, and the nasal spray flu vaccine.
Non-Live or Inactivated Vaccines: These vaccines are generally safer but may be less effective. The immune response can be attenuated, meaning the body may not produce a strong protective antibody response. It is recommended to receive any necessary non-live vaccines at least two weeks before starting Ocrevus, if possible. However, even an attenuated response is better than none, and vaccination with non-live vaccines like the seasonal flu shot is still advised during treatment.
Other Potential Interactions and Precautions
- Hepatitis B (HBV): Ocrevus is contraindicated in patients with an active HBV infection due to the risk of viral reactivation, which can cause serious liver problems. Patients are screened for HBV before starting treatment.
- Other Monoclonal Antibodies and Biologics: As with other immunosuppressants, combining Ocrevus with other biologics that affect immune function can increase the risk of infection. Examples include natalizumab (Tysabri), alemtuzumab (Lemtrada), and others.
- Cancer Medications: While Ocrevus is not chemotherapy, its immunosuppressive nature means that combining it with other cancer therapies requires careful consideration and discussion with your doctor.
- Over-the-Counter Medications and Supplements: No specific interactions with vitamins, herbs, or cannabis have been widely reported, but it is always crucial to inform your doctor about everything you take. Some common over-the-counter pain relievers like ibuprofen are generally considered safe, but confirm with your healthcare provider.
Comparison of Interaction Types
| Interacting Agent | Type of Interaction | Risk/Result | Key Examples |
|---|---|---|---|
| Immunosuppressants & DMTs | Additive immunosuppression | Significantly increased risk of serious infection | Fingolimod (Gilenya), natalizumab (Tysabri), mitoxantrone, interferon drugs |
| Corticosteroids | Additive immunosuppression (high/long-term dose) | Increased risk of infection; high doses may require closer monitoring | Prednisone, methylprednisolone |
| Live Vaccines | Potential infection from weakened pathogen | Cannot be administered during treatment until B-cell repletion | MMR, varicella (chickenpox), nasal spray flu |
| Non-Live Vaccines | Attenuated immune response | Decreased vaccine effectiveness, though still provides some protection | Injected flu vaccine, tetanus, COVID-19 vaccines |
| Hepatitis B Virus | Viral Reactivation | Severe liver problems, potentially fatal | Pre-treatment screening is mandatory |
Important Safety Precautions
- Inform Your Doctor Completely: Provide a full list of all medications, including prescriptions, over-the-counter drugs, and herbal supplements, before starting Ocrevus.
- Communicate with All Healthcare Providers: Ensure all healthcare professionals, including specialists and dentists, are aware you are on Ocrevus, especially regarding vaccination schedules or potential procedures.
- Switching Therapies: If you are transitioning from another MS disease-modifying therapy (DMT), your neurologist will likely plan for a washout period based on the previous drug's lingering effects.
- Avoid Live Vaccines: Steer clear of live vaccines while on Ocrevus. It's best to complete any needed vaccinations well before starting treatment.
- Monitor for Infection: Be vigilant for signs of infection, such as fever, chills, or persistent cough, and report them to your doctor immediately.
Conclusion
Understanding what medications interact with Ocrevus is a critical component of safe and effective multiple sclerosis management. The drug's mechanism of B-cell depletion means interactions with other immunosuppressants and vaccines are a primary concern, posing a risk of heightened infection or reduced vaccine effectiveness. For these reasons, careful communication with your healthcare team is essential to ensure a complete and accurate medication history, proper timing of any vaccinations, and awareness of any other potential risks. By following these guidelines, patients can minimize risks and optimize the therapeutic benefits of Ocrevus. For detailed prescribing information, always consult authoritative resources such as the official FDA Ocrevus label.
Important safety precautions
- Full Medication History: Always provide a comprehensive list of all prescription and non-prescription drugs, as well as supplements, to your doctor before starting Ocrevus to avoid potentially harmful interactions.
- Immunosuppressant Risk: Concurrent use of Ocrevus with other immunosuppressive drugs or immune-modulating therapies significantly increases the risk of serious infections.
- Live Vaccine Contraindication: Live and live-attenuated vaccines, such as MMR and the nasal flu spray, are not recommended during Ocrevus treatment or until B-cell counts recover.
- Vaccine Effectiveness: Non-live vaccines may be less effective during Ocrevus therapy, but they are generally safe to receive. Discuss optimal timing with your doctor.
- Hepatitis B Screening: All patients must be screened for hepatitis B before starting Ocrevus to prevent the risk of viral reactivation.
- Washout Period: If switching from another long-acting immunosuppressant, a washout period is necessary before starting Ocrevus due to the potential for additive immune effects.
