What are the side effects of Briumvi (fenebrutinib)?

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Side Effects of Briumvi (Ublituximab)

Infusion-related reactions are the most common side effects of Briumvi (ublituximab), which is an anti-CD20 monoclonal antibody approved for the treatment of relapsing forms of multiple sclerosis. 1

Primary Side Effects

Briumvi (ublituximab) is a chimeric recombinant IgG1 monoclonal antibody that targets CD20-positive B cells. Based on the available evidence, the following side effects have been observed:

Most Common Side Effects

  • Infusion-related reactions: These are the most frequently reported adverse events following intravenous administration of ublituximab 1
  • Infections: As with other anti-CD20 therapies, patients may experience various types of infections

Potential Serious Side Effects

While specific data for Briumvi is limited in the provided evidence, as an anti-CD20 therapy similar to other agents in this class, the following serious adverse events may occur:

  • Serious infections: Including bacterial, viral, and fungal infections
  • Neutropenia: Reduction in neutrophil count that may increase infection risk
  • Hepatitis B reactivation: In patients with prior hepatitis B infection
  • Progressive Multifocal Leukoencephalopathy (PML): A rare but serious brain infection

Mechanism of Side Effects

Briumvi works by depleting CD20-positive B cells through several mechanisms:

  1. High-affinity binding to CD20 on B cells
  2. B cell depletion through antibody-dependent cellular cytotoxicity
  3. Suppression of immune response

This targeted depletion of B cells, while beneficial for treating multiple sclerosis, can lead to immunosuppression that contributes to the side effect profile 1.

Comparison with Other BTK Inhibitors

It's important to note that Briumvi (ublituximab) is an anti-CD20 monoclonal antibody, not a Bruton's tyrosine kinase (BTK) inhibitor like fenebrutinib. There appears to be some confusion in the question, as fenebrutinib is a different medication than ublituximab.

BTK inhibitors like fenebrutinib have their own side effect profiles:

  • Fenebrutinib specifically affects microglial signaling pathways and can block FcγR activation 2
  • Unlike some BTK inhibitors such as ibrutinib, fenebrutinib has not been associated with significant bleeding risks in clinical trials 3

Monitoring and Management

For patients receiving Briumvi (ublituximab), the following monitoring is recommended:

  • Pre-infusion: Screen for active infections
  • During infusion: Monitor for infusion-related reactions
  • Post-treatment: Regular monitoring for infections and other potential adverse effects

Clinical Considerations

When prescribing Briumvi, clinicians should:

  • Balance the benefits of effective MS treatment against potential risks
  • Be vigilant for new or unexpected side effects, as the side effect profile may evolve with broader use 4
  • Consider patient-specific factors that might increase risk for certain adverse events
  • Educate patients about signs and symptoms that should prompt medical attention

The safety profile of MS treatments continues to evolve as these medications are used in broader populations with various comorbidities and longer durations than studied in clinical trials 4.

References

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Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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