Does the p38 MAP kinase inhibitor pamapimod have potential for the treatment of rheumatoid arthritis?

Methotrexate alone or in combination with other agents is the standard treatment for moderate-to-severe rheumatoid arthritis. As biological agents are expensive, they are not usually used until methotrexate has failed to give a good response. Thus, there is scope for the development of cheaper drugs that can be used instead of methotrexate or in addition to methotrexate. Pamapimod is a p38α inhibitor being developed for use in the treatment of rheumatoid arthritis. The objective of this review was to evaluate the recent clinical trials of pamapimod in subjects with rheumatoid arthritis. There is no clear-cut evidence that pamapimod alone or in the presence of methotrexate is efficacious in subjects with rheumatoid arthritis but it does cause adverse effects. It is unlikely that pamapimod will be useful in the treatment of rheumatoid arthritis.