AstraZeneca releases results from OSKIRA-1 Phase III fostamatinib study

AstraZeneca has announced the results of its OSKIRA-1 Phase III study analysing the efficacy and safety of fostamatinib, which is to be used as an inhibitor for rheumatoid arthritis (RA).

OSKIRA-1 had two primary endpoints, which were to assess the signs and symptoms of RA as measured by ACR20 response rates and an X-ray endpoint known as mTSS (Modified Total Sharp Score).

In the study, fostamatinib achieved a considerable improvement in ACR20 response rate at 24 weeks in both the 100mg twice daily group and the group that obtained 100mg twice daily for four weeks, followed by 150mg once every day compared to placebo (34 per cent).

The safety and tolerability findings for fostamatnib observed in the study were generally consistent with those seen in the past TASKi Phase II programme.

However, there were some adverse events reported in the research, such as diarrhoea, hypertension, nausea, headache and the common cold.

Briggs W. Morrison, executive vice president of Global Medicines Development and Chief Medical Officer, 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."

OSKIRA-1 randomised 923 patients who had suffered an inadequate response to methotrexate, while the effectiveness of two dosing regimens of fostamatinib was also analysed over a 24-week period in combination with MTX versus placebo and MTX.

Patients on fostamatinib stayed on tratement in OSKIRA-1 for 12 months, while the OSKIRA-2 and OSKIRA-3 results are anticipated at some point in the second quarter of this year.

Posted by Neil Clark