Description

Baricitinib is a selective and reversible Janus kinase 1 (JAK1) and 2 (JAK2) inhibitor. Janus kinases belong to the tyrosine protein kinase family and play an important role in the proinflammatory pathway signalling that is frequently over-activated in autoimmune disorders such as rheumatoid arthritis. By blocking the actions of JAK1/2, baricitinib disrupts the activation of downstream signalling molecules and proinflammatory mediators.The drug is approved in Europe.

pharmacologic action

Baricitinib (Olumiant) is a type of drug known as a JAK inhibitor. These drugs work by interfering with the inflammatory processes within the immune system that lead to the symptoms of rheumatoid arthritis.
The substance is quickly absorbed from the gut with an absolute bioavailability of 79%. It reaches highest blood plasma levels after about an hour, in different individuals ranging from 0.5 to 3 hours. Food intake has no relevant influence on the drug's pharmacokinetics. 50% of the circulating baricitinib are bound to blood plasma proteins.

Side-effects and risks

Like any medicine, baricitinib can cause side-effects. Baricitinib and the other JAK inhibitors are a fairly new group of medicines. Because of this, we know less about the risk of longer-term side effects than we do for other medicines used for rheumatoid arthritis. Your rheumatology team should keep you up to date if any new information becomes available about side-effects.

Because baricitinib affects your immune system, it can make you more likely to pick up infections. These include throat, nose and chest infections, cold sores, skin infections (cellulitis) and urinary tract infections. There seems to be a particular risk of shingles (a skin infection caused by the chicken pox virus) in people who take JAK inhibitors.