To date, there are no data to suggest any significant drug interactions between ACTEMRA/RoACTEMRA and other drugs used to treat RA.
- The concomitant administration of a single dose of 10 mg/kg ACTEMRA/RoACTEMRA with 10–25 mg methotrexate (MTX) once weekly had no clinically significant effect on methotrexate exposure.
- Population pharmacokinetic analyses did not detect any effect of methotrexate,
non-steroidal anti-inflammatory drugs (NSAIDs) or corticosteroids on ACTEMRA/RoACTEMRA clearance.
- There is no experience with the use of ACTEMRA/RoACTEMRA in combination with anti-TNFs or other biologic treatments for RA. ACTEMRA/RoACTEMRA is not recommended for use in combination with other biologics.
- The expression of hepatic cytochrome P450 (CYP450) enzymes is suppressed by cytokines, such as IL‑6, that stimulate chronic inflammation. Thus, CYP450 expression may be enhanced by ACTEMRA/RoACTEMRA therapy. In vitro studies suggest that ACTEMRA/RoACTEMRA normalises expression of CYP1A2, CYP2C9, CYP2C19 and CYP3A4 in cultured human hepatocytes treated with IL-6.
- Patients taking concomitant medications that are metabolised by these cytochromes (e.g. atorvastatin, calcium channel blockers, ciclosporin, etc.) who initiate treatment with ACTEMRA/RoACTEMRA should be monitored in order to ensure that therapeutically effective dosing levels are maintained. As ACTEMRA/RoACTEMRA has a long half-life, the effect on these drugs may persist for several weeks after treatment discontinuation.
RoACTEMRA® (tocilizumab) Summary of Product Characteristics. Roche Registration Limited. August 2011.