IDEC Shares Fall As Arthritis Drug Stalls

IDEC Pharmaceuticals Corp and SmithKline Beecham have suspended furtherenrollment and treatment in the Phase III and supportive clinical trials of IDEC -CE9.1/SB-210396, an anti-CD4 antibody for the treatment of rheumatoid arthritis.

IDEC's shares fell by 10.6% on the day of the announcement to $23.25, and by the end of the Marketletter's reporting week (June 25) had dipped below $23.

This decision was taken after it became apparent that around a third of the patients taking the drug exhibited depressed CD4 cell counts. This occurred in an unexpectedly high number of treated patients in the Phase III study compared to the rate observed in the Phase II trial that was reported last year at the American College of Rheumatology meeting (Marketletter October 28, 1996).