Kineret (anakinra) is an injectable medicine approved by the U.S. Food and Drug Administration (FDA) and the European Medicines Agency (EMA) for the treatment of rheumatoid arthritis (RA) and cryopyrin-associated periodic syndromes, or CAPS.

The drug, developed by Sobi, also is under investigation as a potential treatment for juvenile arthritis (JA), a group of diseases that cause pain, swelling, stiffness, and loss of motion in the joints of children. Australia is the only country that has approved Kineret to treat active JA in patients ages 2 or older who have not responded adequately to non-biological disease-modifying, anti-rheumatic drugs (DMARDs).

Although the exact causes of RA and JA are unknown, they are considered to be autoimmune diseases in which the immune system mistakenly attacks healthy tissues in the body.

How Kineret works

The active substance is anakinra, a recombinant receptor antagonist that was designed to block the receptors of a protein known as interleukin-1 (IL-1). IL-1 plays an important role in the immune system, but can cause uncontrollable inflammation if produced in excess, as is the case in RA and CAPS.

By preventing the attachment of IL-1 to its receptors, Kineret blocks the activity of IL-1 and helps to reduce inflammation and relieve the symptoms of arthritis.

Kineret in clinical trials for JA

The FDA based its approval of Kineret for RA on several clinical trials that incorporated data from more than 1,790 adults with active RA. The results of these trials showed that Kineret reduced the signs, symptoms, and progression of the disease.

It was then studied in two clinical trials as a treatment for JA.

A Phase 2 trial (NCT00037648) evaluated the preliminary effectiveness, safety, and pharmacokinetics of daily, single, under-the-skin injections of the drug in 86 patients with JA. Published results of the trial showed the drug was safe and well-tolerated, with very low infection rates, and no clinically significant abnormalities in laboratory data. However, the effectiveness of Kineret could not be demonstrated because of the small number of participants in the trial.

A randomized, placebo-controlled, Phase 2/3 trial (NCT00339157) assessed the effectiveness of Kineret in 24 JA patients, ages 2 to 20. The trial consisted of a one-month period of either Kineret or placebo treatment, followed by 11 months of open-label Kineret treatment. Results showed that Kineret treatment was effective in JA, with 8 out of 12 patients receiving Kineret responding to treatment compared to only one patient receiving placebo responding. However, the effect seemed to be a short-term, because the response was lost in most patients over time. Six patients stopped treatment owing to an adverse event, lack of effectiveness, or a disease flare.

A single-center study, to review 25 patients with JA treated with Kineret for at least six months, showed the drug is associated with a rapid achievement of inactive disease in a significant portion of patients, with a better outcome with earlier treatment from disease onset.

Kineret is currently being evaluated in a Phase 3 study (NCT03265132), called anaSTILLs. The trial aims to demonstrate the effectiveness and evaluate the safety, pharmacokinetics (movement in the body), and immunogenicity (ability to trigger an immune response) of the drug in 81 patients with JA and adult-onset Still’s disease (AOSD). The trial is recruiting patients in Kansas City, Missouri.

Other details

The most common side effects associated with Kineret are injection-site reactions, headache, nausea, diarrhea, sinus infection, joint pain, and stomach pain.

***

Note: Juvenile Arthritis News is strictly a news and information website about the disease. It does not provide medical advice, diagnosis or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.