Newly approved oral drug is effective in patients with rheumatoid arthritis
The U.S. Food and Drug Administration (FDA) approved a new drug for treating moderate to severe rheumatoid arthritis. The new drug, tofacitinib, which is an oral JAK inhibitor, has been tested in several clinical trials and has been shown to slow the progression of disease in patients who are non-responsive to metrotextat.
The study further confirms previous studies which indicated that tofacitinib is effective in treating symptoms of rheumatoid arthritis. “Our findings provide the first evidence that tofacitinib reduces the progression of structural damage in RA patients with active disease,” said lead investigator Dr. DÃ©sirÃ©e van der Heijde from Leiden University Medical Center in The Netherlands.
Rheumatoid arthritis is a systemic autoimmune disease that mainly affects the joints, but it can affect other organs such as the lungs, heart, kidneys, skin, etc.. The disease usually occurs in adulthood, generally in the range of 40-50 years and affects more women than men. Although it is not known by what mechanism or what causes this illness, it is supposed that it is due to the activation of autoantibodies against the synovium, which is part of the joint. This immune attack against joint structures determines several symptoms such as inflammation, pain, stiffness. Rheumatoid arthritis mainly affects the small joints of the hand, in a symmetrical manner, and leads to specific deformity (ulnar deviation of the hand). Over time, patients begin to have difficulty in movement, which may go up to stiffness and ankylosis , which seriously affects quality of life.
Rheumatoid arthritis, like many other autoimmune diseases, is treated with immunosuppressive, anti-inflammatory, biological agents, etc.. The problem is that not all patients respond to treatment, so researchers wanted to find other types of drugs to help patients with rheumatoid arthritis. Dr. van der Heijde said that the new drug, tofacitinib, works by inhibiting certain enzymes (Janus kinase – JAK- enzymes) found in white blood cells and involved in immunity. She said that oral JAK inhibitor tofacitinib is a part of anti-inflammatory disease-modifying drugs (DMARD), that is drugs that regulate the immune system in rheumatoid arthritis.
The study was a phase 3 clinical trial and included 797 patients who were divided into 4 groups to receive either tofacitinib in different doses or placebo. It was demonstrated that patients who received tofacitinib (5 and 10 mg) displayed less disease progression and a joint space narrowing compared with patients receiving placebo. The effect of this drug has been also demonstrated by radiological investigations as there were more patients receiving tofacitinib than those receiving placebo with no radiographic progression of the disease.