The Japanese Ministry of Health, Labor and Welfare (MHLW) has approved Pfizer's Xeljanz (tofacitinib citrate) for the treatment of adults with rheumatoid arthritis (RA) who have had an inadequate response to existing therapies. Xeljanz may be used in patients in whom clinical symptoms due to the disease remain even after appropriate treatment with at least one other disease-modifying antirheumatic drug (DMARD), such as methotrexate. The recommended dose of Xeljanz is 5 mg twice daily.

Xeljanz will be commercially available in Japan after the National Health Insurance listing and will be co-promoted in Japan by Pfizer and Takeda Pharmaceutical Company Limited. Pfizer and Takeda also currently co-promote the RA drug Enbrel (etanercept) in Japan.

Xeljanz (ZEL’ JANZ’) is the first approved oral treatment in a new class of medicines known as Janus kinase (JAK) inhibitors. Initially, Xeljanz will be made available in Japan to medical institutions participating in an all-patient surveillance programme.

“RA is a serious and disabling disease and there is a need for new treatment options, as a significant number of patients do not adequately respond to current therapies,” said Mark Swindell, Head of Pfizer Specialty Care Business Unit in Japan. “We are proud of our strong portfolio of treatments for inflammatory disorders in Japan, and we are pleased with the approval of Xeljanz, which allows us to offer an additional treatment option for RA patients.”

Unlike biologic therapies that target RA outside the cell, Xeljanz targets the disease from inside the cell. It is specifically designed to inhibit the Janus kinase (JAK) pathways, which are signalling pathways inside the cell that play a role in the inflammation involved in RA.

The approval of Xeljanz in Japan is supported by a multi-study, global clinical development programme, which evaluated Xeljanz in approximately 5,000 patients across various RA patient populations. The application also included data from Japanese subjects from two phase 2 studies, one phase 3 study and an ongoing long-term extension study. Across five global pivotal trials, Xeljanz 5 mg twice daily demonstrated efficacy, whether administered alone or in combination with a non-biologic DMARD, such as methotrexate, in patients who had a previous inadequate response to non-biologic or biologic DMARDs, including tumour necrosis factor (TNF) inhibitors.

Xeljanz is approved for the treatment of RA patients who have had an inadequate response to existing therapies. Notable safety findings observed in the Xeljanz RA programme include serious and other important infections, including tuberculosis and herpes zoster; malignancies, including lymphoma; gastrointestinal perforations; decreased neutrophil and lymphocyte counts; and lipid elevations. The most common serious adverse events were serious infections. The most commonly reported adverse events were upper respiratory tract infections, headache, nasopharyngitis and diarrhoea.