July 15 2013 | By Márcio Barra
Pfizer just issued a press release where it reports that Switzerland’s SwissMedic has approved its rheumatoid arthritis treatment Xeljanz (tofacitinib citrate) for sale. This makes Switzerland the first European country to approve Xeljanz for adult patients with moderate-to-severe active RA who had an inadequate response or intolerance to the antirheumatic agent methotrexate.
Xelnjaz was launched in the US this past November following a positive approval by the FDA. FDA’s approval made tofacitinib the first oral antirheumatic drug in more than 10 years. However, Pfizer didn’t get the same response from Europe, with the EMA’s committee for Medicinal Products for Human Use’s issuing a negative approval back in April, on the grounds that the clinical studies conducted didn’t show a consistent reduction in disease activity and joints structural damage, alongside safety concerns. Pfizer is currently seeking a re-examination of the Committee’s negative opinion.
Tofacitinib, the active ingredient of Xeljanz, is an inhibitor of the janus kinase (JAK) family, particularly JAK 3. JAK are enzymes that play a crucial role in the process of inflammation and damage of the joints.By blocking the enzymes, the drug reduces the inflammation and other symptoms of rheumatoid arthritis.
Abbott, owner of the biologic blockbuster Humira (the world’s current top selling drug), is planning to enter the JAK inhibitors market. Last year it licensed the rights to GLPG0634, a selective JAK-1 inhibitor from Galapagos NV. Phase 2B studies are scheduled to start soon.
Other drugs for treating RA include “disease-modifying antirheumatic drugs”, drugs that slow the progression of joint damage from rheumatoid arthritis. These include Enbrel from Pfizer/Amgen, the aforementiond Humira from Abbott, Remicade from Johnson & Johnson/ Merck, Cimzia from UCB and Simponi from Johnson & Johnson. All five of these drugs are TNF inhibitors. For patients that do not respond to TNF inhibitors, other treatments available include Rituxan from Roche/ Biogen Idec, a B cell depletory; Orencia from Bristol-Myers Squibb, a T-cell inhibitor; and Actemra from Roche, an IL-6 inhibitor.