Tocilizumab and Abatacept: Interaction Details
AI-assisted, pharmacist-reviewed · AI content regenerated Jul 16, 2026 · Source data updated Jul 16, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Tocilizumab
Abatacept
How we grade severity & evidence
Severity levels
- Contraindicated: These should generally not be used together.
- Major: Potentially serious — often needs a change or close monitoring.
- Moderate: Can be significant — usually manageable with monitoring.
- Minor: Usually limited clinical impact.
Evidence grades
- Established: Well documented — supported by controlled studies or strong clinical data.
- Probable: Good supporting evidence, though not definitively proven.
- Suspected: Some evidence suggests this interaction, but it is not well established.
- Possible: Limited or conflicting evidence; the interaction may occur.
- Theoretical: Predicted from the drugs' pharmacology; not yet confirmed in people.
Ratings come from the documented interaction literature and are reviewed by a pharmacist. They describe the documented risk of the combination, not what will necessarily happen to you — your dose, timing, and health picture all matter.
Both of these medicines calm down an overactive immune system. Tocilizumab (Actemra) and abatacept (Orencia) are both biologic drugs used for conditions like rheumatoid arthritis. Each one works on your immune system in its own way. When you take two of them together, your immune system can get turned down too far, which makes it harder for your body to fight off infections.
Studies with similar combinations found more serious infections and no extra benefit, which is why using two of these biologics at the same time is generally not recommended. The good news is that your care team knows about this, and they can choose the safest plan and watch you closely for any signs of infection.
Effect: Additive immunosuppression from combining two biologic DMARDs, increasing risk of serious infection with no added therapeutic benefit.
- Mechanism: Unknown/pharmacodynamic overlap; neither agent is a prodrug and this is not a CYP-mediated PK interaction. Both broadly suppress immune activity (tocilizumab is an IL-6 receptor antagonist; abatacept modulates T-cell costimulation).
- Evidence: Theoretical/extrapolated (data derive from abatacept plus TNF antagonists).
- Severity/Onset: Major; onset unspecified.
- Management: Concurrent use of abatacept with other RA/PsA biologics is not recommended. If transitioning off a biologic, monitor for signs and symptoms of infection.
What happens
An increased risk of infection
Interaction Deep Dive
In controlled clinical trials, combining abatacept with tumor necrosis factor (TNF) antagonists led to a higher risk of serious infection while offering no extra therapeutic benefit. Because there is not enough data to assess how safe and effective abatacept is when given alongside anakinra or other biologics used for rheumatoid arthritis or psoriatic arthritis, using these agents together is not advised. Patients being switched from TNF antagonist therapy to abatacept should be watched for signs of infection1.
Why it happens (mechanism)
Unknown
How to manage this interaction
The main point: using tocilizumab and abatacept together is generally not recommended because it raises the risk of serious infection without adding benefit.
- Do not start or stop either medicine on your own. Keep taking what has been prescribed and let your care team decide the best single therapy for you.
- Your care team will typically choose one biologic rather than both, and may transition you from one to the other.
- If you are switching between these medicines, expect your team to watch you more closely for signs of infection.
- Call your pharmacist or prescriber right away if you notice fever, chills, cough, or any sign of an infection.
Management is individual — confirm any change with your pharmacist or prescriber.
Literature reports
2 reports — tap to read
a) Taking abatacept together with etanercept produced no extra efficacy but raised the risk of serious infection when compared with etanercept used alone. In a 1-year randomized study (N=121) that was followed by an open-label long-term extension (LTE; n=80), patients with rheumatoid arthritis who were already receiving etanercept 25 mg twice/week continued that etanercept and were assigned at random to receive either abatacept 2 mg/kg IV on days 1, 15, and 30 and then every 4 weeks (n=85) or placebo (n=36). After the double-blind phase ended, patients could enter the LTE phase, at which point the abatacept dose was raised to roughly 10 mg/kg. At 6 months, the 2 mg/kg abatacept group demonstrated no meaningful improvement versus the placebo group in modified American College of Rheumatology 20% (ACR20; 48.2% vs 30.6%) or ACR50 (25.9% vs 19.4%) response rates, though a significant difference was seen in modified ACR70 rates (10.6% vs 0%). At 1 year, there were no significant differences between the two groups in ACR20, 50, or 70 response rates. Serious adverse events occurred more often in the 2 mg/kg abatacept group (16.5%) at one year and in the 10 mg/kg abatacept group after 2 years of LTE (32.5%) than in the placebo group (2.8%). Serious infections at 1 year were reported in 3.5% of the 2 mg/kg abatacept group and in 0% of the placebo group 2.
b) In controlled clinical trials involving adults with active rheumatoid arthritis who were given abatacept along with a tumor necrosis factor (TNF) antagonist (n=204), compared with TNF antagonist therapy by itself (n=134), the rate of infection (63% vs 43%, respectively) and of serious infection (4.4% vs 0.8%, respectively) was higher with the combined treatment; moreover, the combined treatment offered no added benefit 1.
Common questions
Can I take Tocilizumab and Abatacept together?
Taking tocilizumab and abatacept together is generally not recommended because it can raise your infection risk without extra benefit; let your care team pick one biologic and watch you closely if switching. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Tocilizumab and Abatacept interaction?
It is rated major. Potentially serious — often needs a change or close monitoring.
How quickly could this interaction happen?
The documented onset is "unspecified". The timing of this interaction is not well characterized.
How is the Tocilizumab and Abatacept interaction managed?
The main point: using tocilizumab and abatacept together is generally not recommended because it raises the risk of serious infection without adding benefit. Do not start or stop either medicine on your own. Keep taking what has been prescribed and let your care team decide the best single therapy for you. Your care team will typically choose one biologic rather than both, and may transition you f… Management is individual — always follow your own care team's guidance.
How strong is the evidence for this interaction?
The evidence is graded "theoretical". Predicted from the drugs' pharmacology; not yet confirmed in people.
Questions for your pharmacist
- Does my dose of Tocilizumab or Abatacept need adjusting while I take them together?
- What symptoms should prompt me to call you or my prescriber right away?
- Does the timing of my doses matter for this combination?
- Is there a safer alternative to one of these medications for me?
References (2)
- Product Information: ORENCIA(R) intravenous, subcutaneous injection, abatacept intravenous, subcutaneous injection. Bristol-Myers Squibb Company (per FDA), Princeton, NJ, 2020. DailyMed
- Weinblatt M, Schiff M, Goldman A, et al: Selective costimulation modulation using abatacept in patients with active rheumatoid arthritis while receiving etanercept: a randomised clinical trial. Ann Rheum Dis 2007; 66(2):228-234. PubMed
Keep reading about Tocilizumab
Keep reading about Abatacept
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