Does Rhapsido (Remibrutinib) Cause Cold Sores?
Based on the available safety data from clinical trials, remibrutinib does not appear to cause herpes labialis (cold sores) as a recognized adverse effect. The most common infections reported with remibrutinib are upper respiratory tract infections and nasopharyngitis, not herpes reactivation 1, 2.
Safety Profile of Remibrutinib
The comprehensive safety data from the phase 3 REMIX trials and extension studies consistently identify the following infection-related adverse events:
- Upper respiratory tract infections occur more frequently with remibrutinib compared to placebo (RR 2.88-2.89) 3, 4
- Nasopharyngitis is increased with remibrutinib treatment (RR 1.88) 3
- General infections are reported in approximately 30.9% of patients, but these are predominantly respiratory in nature 1
What the Clinical Trial Data Shows
In the 52-week extension study evaluating long-term safety, the three most common adverse events by system organ class were:
- Infections (30.9% of patients)
- Skin and subcutaneous tissue disorders (26.8%)
- Gastrointestinal disorders (16.5%) 1
Importantly, herpes labialis or cold sores are not listed among the common adverse events in any of the published safety analyses from the REMIX-1, REMIX-2, or extension studies 1, 2.
Overall Safety Considerations
- Most treatment-emergent adverse events with remibrutinib are mild to moderate and considered unrelated to the medication by investigators 1
- The safety profile remains consistent and favorable over 52 weeks of continuous treatment 2
- Serious adverse events occur at rates similar to placebo (RR 1.85, p = 0.37) 4
Common Pitfall to Avoid
Do not confuse the increased risk of upper respiratory infections with herpes simplex virus reactivation—these are distinct entities. While BTK inhibitors as a class can theoretically affect immune function, the specific adverse event profile of remibrutinib in CSU patients does not include herpes labialis as a recognized complication 3, 4.