For those of us with RA who regularly self-inject medicines (biologicals and/or methotrexate), a new set of oral medications are being developed. These are called kinase inhibitors and they show potential in treating the inflammation caused by RA. Kinases are molecules that have been linked to cellular pathways that produce inflammation-causing cytokine proteins. In RA, it’s these cytokines that ultimately cause the tissue destroying symptoms (see earlier post). If you’d like to read more about the biochemical processes involved with kinases, download on this brief article from the Journal of Rheumatology.
kinase signaling
Kinase inhibitor drugs are being developed for multiple diseases including some forms of cancer, diabetes, and inflammatory diseases including rheumatoid arthritis. A recent book published in 2009[i] documents over 100 potential kinase inhibitor medicines. It is reported that this class of drugs have huge marketing and profit potentials (upwards of $58 billion in 2010). [ii]
In a recent video, Dr. Gray Firestein from the University of California San Diego mentions the potential of two oral kinase inhibitors for RA currently in human clinical trials. The first group is called Spleen tyrosine kinase (STK) inhibitors. [iii] [iv] The pharmaceutical company AstraZeneca is already preparing for the manufacture and distribution of a new STK inhibitor called fostamatinib disodium.[v]
Another class of drugs are called janus kinase (JAK) inhibitors. According one group of researchers working with a JAK drug being tested by the pharmaceutical company Pfizer,
“Researchers tested several doses of the Pfizer drug in 24-week, Phase II studies, with some proving highly effective in providing relief from rheumatoid arthritis symptoms and near remission of disease activity…”[vi]
Comparisons between the JAK oral kinase inhibitors and common biological drugs like Humira are being planned. There have been a few side effects noticed in the clinical trials including diarrhea, increased cholesterol levels, and increased blood pressure. [vii] But according to one published study,
“If the results seen in phase 2 studies are confirmed in larger phase 3 studies, we may soon have new, oral DMARD therapies available.”[viii]
I’m encouraged by the new potential kinase inhibitor oral treatments for RA. Perhaps someday in the near future, I’ll be popping pills instead of injecting Humira. This is good news because a large group of RA patients do not respond to the biological therapies. [ix]
A reader send me an informative article on Kinase inhibitors (click here for PDF file on oralkinaseinhibitors).
Postscript to my last post…all tests for diabetes and hypothyroidism were negative!
[i] http://www.wiley.com/WileyCDA/WileyTitle/productCd-0470278293.html
[ii] http://www.drugresearcher.com/Research-management/Report-predicts-kinase-market-to-reach-58.6bn-in-2010
[iii] http://www.ncbi.nlm.nih.gov/pubmed/18447591
[iv] http://jpet.aspetjournals.org/content/319/3/998.full
[v] http://www.nature.com/nrd/journal/v9/n4/full/nrd3155.html
[vi] http://www.reuters.com/article/idUSN1631123820091017
[vii] http://www.ncbi.nlm.nih.gov/pubmed/18447591
[viii] http://journals.lww.com/co-rheumatology/Abstract/2010/05000/Kinase_inhibitors__a_new_approach_to_rheumatoid.16.aspx
[ix] http://www.nature.com/nature/journal/v423/n6937/full/nature01661.html
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