Humira vs Xeljanz
Injection versus tablet in rheumatoid arthritis — and the safety warnings that led regulators to reserve JAK inhibitors for after an anti-TNF has failed.
At a glance
Key differences
- Different classes. Humira is a TNF inhibitor; Xeljanz is a JAK inhibitor. They act on different targets in the body.
- Time on the market. Humira was first approved by the FDA in 2002, Xeljanz in 2012. That gives Humira roughly 10 more years of real-world use and long-term safety data.
- Who markets them. Humira is marketed by AbbVie; Xeljanz by Pfizer.
What each one treats
HUMIRA is a tumor necrosis factor (TNF) blocker indicated for: Reducing signs and symptoms, inducing major clinical response, inhibiting the progression of structural damage, and improving physical function in adult patients with moderately to severely active r heumatoid a rthritis . ( 1.1 ) Reducing signs and symptoms of moderately to severely active polyarticular juvenile idiopathic arthritis in patients 2 years of age and older. ( 1.2 ) Reducing signs and symptoms, inhibiting the progression of structural damage, and improving physical function in adult patients with active psoriatic arthritis . ( 1.3 ) Reducing signs and symptoms in adult patients with active ankylosing spondylitis . ( 1.4 ) Treatment of moderately to severely active Crohn’s disease in adults and pediatric patients 6 years of age and older. ( 1.5 ) Treatment of moderately to severely active ulcerative colitis in adu…
XELJANZ (tablets and oral solution) and XELJANZ XR (extended-release tablets) are Janus kinase (JAK) inhibitors. XELJANZ tablets and XELJANZ XR are indicated for the treatment of adult patients with: • Moderately to severely active rheumatoid arthritis (RA), who have had an inadequate response or intolerance to one or more TNF blockers. • Active psoriatic arthritis (PsA), who have had an inadequate response or intolerance to one or more TNF blockers. • Active ankylosing spondylitis (AS), who have had an inadequate response or intolerance to one or more TNF blockers. • Moderately to severely active ulcerative colitis (UC), who have had an inadequate response or intolerance to one or more TNF blockers. XELJANZ (tablets and oral solution) are indicated for the treatment of pediatric patients 2 years of age and older with: • Active PsA, who have had an inadequate response or intolerance to …
How each one works
12.1 Mechanism of Action Adalimumab binds specifically to TNF-alpha and blocks its interaction with the p55 and p75 cell surface TNF receptors. Adalimumab also lyses surface TNF expressing cells in vitro in the presence of complement. Adalimumab does not bind or inactivate lymphotoxin (TNF-beta). TNF is a naturally occurring cytokine that is involved in normal inflammatory and immune responses. Elevated concentrations of TNF are found in the synovial fluid of patients with RA, JIA, PsA, and AS and play an important role in both the pathologic inflammation and the joint destruction that are hallmarks of these diseases. Increased concentrations of TNF are also found in psoriasis plaques. In P…
12.1 Mechanism of Action Tofacitinib is a Janus kinase (JAK) inhibitor. JAKs are intracellular enzymes which transmit signals arising from cytokine or growth factor-receptor interactions on the cellular membrane to influence cellular processes of hematopoiesis and immune cell function. Within the signaling pathway, JAKs phosphorylate and activate Signal Transducers and Activators of Transcription (STATs) which modulate intracellular activity including gene expression. Tofacitinib modulates the signaling pathway at the point of JAKs, preventing the phosphorylation and activation of STATs. JAK enzymes transmit cytokine signaling through pairing of JAKs (e.g., JAK1/JAK3, JAK1/JAK2, JAK1/TyK2, …
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- FDA Drug Label (openFDA) ↗ Indications, mechanism of action and pharmacologic class
- Drugs@FDA ↗ First FDA approval date and the company holding the application
- FDA Drug Shortage Database ↗ Current US supply / shortage status
Plain-English summaries and drug-class explainers are written and reviewed by Sreepriya Prasannan (MSc Digital Transformation of Life Sciences (Innopharma Education / Griffith College); MSc & BSc Botany). Data is retrieved automatically from the sources above and cross-checked with AI-assisted verification (Anthropic's Claude) — brand and generic names are matched against the exact FDA product record so that a combination product or a different formulation cannot be mistaken for the drug on this page. An editor reviews the result before publication. We describe this in full in our editorial standards and corrections policy. The FDA data on this page was last retrieved on 9 Oct 2026. How every register is built: methodology · fixes we have made: corrections log.