AstraZeneca unveils positive results for arthritis treatment study

Biopharmaceutical business AstraZeneca has unveiled positive results from a study of fostamatinib, an oral drug being developed for the treatment of rheumatoid arthritis.

In the FTSE 100 company's phase III study, designed to assess the efficacy and safety of fostamatinib, the drug achieved a "statistically significant improvement" in the ACR20 [American College of Rhematology] response rate in patients compared to a placebo.

The ACR score represents the percentage improvement in symptoms in patients, such as tenderness and swelling in the joints.

To qualify for an ACR20, a number of criteria need to be fulfilled. This includes a person with rheumatoid arthritis having at least 20% fewer tender joints and at least 20% fewer swollen joints.

In the study, entitled OSKIRA-1, AstraZeneca said that fostamatinib achieved a "statistically significant improvement in ACR20 response rate at 24 weeks in both the 100 mg twice daily group and the group that received 100 mg twice daily for four weeks followed by 150 mg once daily" when compared to placebo.

The group added that fostamatinib did not demonstrate a statistically significant difference in mTSS [modified Total Sharp Score] compared to placebo at 24 weeks for either dose.

The radiographic modified Total Sharp Score is measured in the hands and feet using X-rays. mTSS is a measure of bone erosion and joint space narrowing on X-rays. A smaller change in mTSS over a given time period, given in percentage change of mTSS score, reflects less progression of joint damage.

AstraZeneca further reported that the safety and tolerability findings for fostamatinib observed in the OSKIRA-1 study were generally consistent with those previously reported for the TASKi Phase II programme.

Briggs Morrison, Managing Director and Executive Vice President of Global Medicines Development and Chief Medical Officer at AstraZeneca, said: "These top-line results provide important information on the efficacy and safety of fostamatinib and demonstrate that the compound has an effect on the signs and symptoms of rheumatoid arthritis.

"We will await the results of the remaining Phase III studies, OSKIRA-2 and OSKIRA-3, to further evaluate and characterise the profile of fostamatinib as a potential treatment for rheumatoid arthritis."

The OSKIRA-2 and OSKIRA-3 results are expected later in the second quarter of 2013.

MF