When to Switch to Subcutaneous Infliximab? The RE-WATCH Multicenter Study.

Area of Science:

• Gastroenterology and Hepatology
• Pharmacology and Therapeutics
• Clinical Trial Research

Background:

• Infliximab (IFX) biosimilar CT-P13 offers both intravenous (IV) and subcutaneous (SC) formulations.
• Current guidelines permit switching from IV to SC CT-P13 after two IV administrations.
• Some clinicians delay SC switch until stable clinical remission is achieved.

Purpose of the Study:

• To compare the efficacy and safety of early versus late switching from IV to SC CT-P13.
• To evaluate endoscopic response, treatment persistence, clinical remission, endoscopic remission, and safety after one year.
• To assess the impact of switch timing on patient outcomes and treatment retention.

Main Methods:

• A prospective study comparing two groups: early switch (IV to SC CT-P13 at 6 weeks) and late switch (at 6 months).
• Evaluated endoscopic response, steroid-free clinical remission, endoscopic remission, and IFX retention rate at one year.
• Monitored clinical indexes, fecal calprotectin, C-reactive protein (CRP), and adverse events.

Main Results:

• No significant differences were observed between early and late switch groups in endoscopic response (71.4% vs 70.8%), steroid-free clinical remission (62.5% vs 68.7%), or IFX retention rate (75.0% vs 66.7%) at one year.
• Early switch group showed a trend towards higher endoscopic remission rates (69.6% vs 52.1%), though not statistically significant.
• Adverse events were comparable between groups (4.5% vs 8.3%), with a low rate of return to IV-IFX.

Conclusions:

• Early switch from IV-IFX to SC-IFX at 6 weeks is effective and yields similar clinical and endoscopic remission rates at one year compared to a late switch at 6 months.
• The findings support the efficacy and safety of an early transition to subcutaneous infliximab biosimilar.
• This strategy offers comparable outcomes to delayed switching, potentially improving patient convenience and treatment adherence.