What is the Difference Between Baricitinib Tofacitinib and Upadacitinib?

Baricitinib, tofacitinib, and upadacitinib are JAK inhibitors used for the treatment of rheumatoid arthritis (RA) and other inflammatory conditions. They have different inhibitory profiles against the JAK family of enzymes (JAK1, JAK2, JAK3, and TYK2). Here are the main differences between these three drugs:

1. Inhibitory Profile:

• Tofacitinib is a potent JAK1 and JAK3 inhibitor but is less active against JAK2 and TYK2.
• Baricitinib is a selective oral JAK1 and JAK2 inhibitor with moderate activity against TYK2 and significantly less inhibition of JAK3.
• Upadacitinib is an oral JAK1-selective inhibitor.

1. Efficacy:

• In a study comparing the efficacy of these drugs in RA patients, baricitinib and filgotinib were found to be equivalent therapeutic alternatives compared to upadacitinib.
• Tofacitinib showed a higher ACR70 response rate compared to filgotinib 100 mg.

1. Safety:

• Tofacitinib 5 mg, filgotinib 200 mg, and placebo showed a significantly lower serious adverse event rate than upadacitinib 15 mg.

In summary, baricitinib, tofacitinib, and upadacitinib are JAK inhibitors with different inhibitory profiles against JAK enzymes. They have varying efficacy and safety profiles in the treatment of RA, with baricitinib and filgotinib showing equivalent therapeutic alternatives to upadacitinib, and tofacitinib having a higher ACR70 response rate compared to filgotinib 100 mg.

Comparative Table: Baricitinib Tofacitinib vs Upadacitinib

Here is a table comparing the differences between baricitinib, tofacitinib, and upadacitinib:

According to the available data, tofacitinib is a potent JAK1 and JAK3 inhibitor but is less active against JAK2 and TYK2. Baricitinib inhibits JAK1/3 signaling to a lesser extent than upadacitinib and tofacitinib, while upadacitinib, baricitinib, and tofacitinib inhibit the signaling of JAK2/2-dependent cytokines, including GM-CSF and IL-3, as well as the signaling of the JAK2/TYK2-dependent cytokine G-CSF.

In a study comparing the efficacy of tofacitinib and baricitinib in patients with rheumatoid arthritis, no significant difference was observed in patient characteristics between the tofacitinib and baricitinib groups, and the baricitinib group had a significantly higher rate of CDAI remission at week 24 after the introduction. However, further investigation is required in an accurately powered head-to-head trial.