The two primary endpoints of OSKIRA-1were evaluation of signs and symptoms of RA as measured by ACR20 response rates, and an X-ray endpoint referred to as modified Total Sharp Score (mTSS).
AstraZeneca global medicines development executive vice president and chief medical officer Briggs Morrison said the top-line results demonstrate fostamatinib’s efficacy on the signs and symptoms of rheumatoid arthritis.
"We will await the results of the remaining Phase 3 studies, OSKIRA-2 and OSKIRA-3, to further evaluate and characterize the profile of fostamatinib as a potential treatment for rheumatoid arthritis," Morrison added.
A statistically significant improvement in ACR20 response rate at 24 weeks was achieved by fostamatinib in both the 100mg twice daily group and the group that received 100mg twice daily for four weeks subsequent to 150mg once daily.
A statistically significant difference in mTSS compared to placebo at 24 weeks for either dose was not achieved.
Consistent safety and tolerability findings for fostamatinib were noted.
The commonly reported adverse events include hypertension, diarrhoea, nausea, headache and nasopharyngitis.