EMA begins review of Pfizer's new rheumatoid arthritis drug

European regulators have began to review Pfizer's new rheumatoid arthritis treatment tofacitinib.

The oral JAK inhibitor had been submitted to the European Medicines Agency (EMA) for marketing authorisation in the treatment of moderate-to-severe active rheumatoid arthritis (RA).

If approved, tofacitinib would offer competition to anti-TNF drugs like Abbott's Humira (adalimumab), Johnson & Johnson's (J&J) Remicade (infliximab) and Pfizer's Enbrel (etanercept).

Earlier this month analysts at Decision Resources predicted tofacitinib would likely be used ahead of the anti-TNFs and also have a bigger impact on the market than another new RA drug in development, AstraZeneca's Syk inhibitor fostamatinib disodium.

Pfizer's submission to the EMA is based partly on the phase III ORAL (Oral Rheumatoid Arthritis Phase III TriaLs) programme.

The programme consists of five studies involving tofacitinib, which all met their primary endpoints.

Trial successes included tofacitinib monotherapy achieving a 20 per cent or greater reduction in the number of tender and swollen joints in two thirds of participants.

Around 5,000 individuals with RA over 35 countries have so far been treated with tofacitinib in clinical trials. The drug is also undergoing investigation in two further ongoing long-term open-label extension studies.

The EMA's announcement comes a week after the first JAK inhibitor was approved for marketing was launched in the US.

Regulatory authorities in the US cleared Incyte Corp's Jakafi (ruxolitinib) for use in the treatment of the rare bone marrow disease myelofibrosis.