December saw shares of Rigel Pharmaceuticals (RIGL +1.97%) drop more than 20%. The tumble happened after Rigel's partner AstraZeneca (AZN 0.13%) released phase 2b data concerning their experimental rheumatoid arthritis drug fostamatinib. While the drug outperformed the placebo, it failed to beat AbbVie's (ABBV 0.11%) Humira. (AbbVie, formerly the branded pharmaceutical division of health care powerhouse Abbott Labs (ABT +0.35%), is now listed on the NYSE). In this video, Motley Fool health care analysts Max Macaluso and Brenton Flynn break down this story for investors.
Why Rigel Pharmaceuticals Lost Big in December
By Max Macaluso and Brenton Flynn – Jan 2, 2013 at 5:00PM
NASDAQ: RIGL
Rigel Pharmaceuticals

Market Cap
$527M
Today's Change
(1.97%) $0.58
Current Price
$29.97
Price as of October 24, 2025 at 4:00 PM ET
Rigel Pharmaceuticals took a big hit in December. Here's why.
About the Author
Max is the Technology, Biopharma & Health Care Bureau Chief at Fool.com. Prior to joining the Fool, he completed a PhD in chemistry at the University of Cambridge and an MBA at the College des Ingenieurs.
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