The Los Angeles Business Journal’s index of largest local public companies closed down slightly for the week.

The weighted LABJ Stock Index closed down 0.01 percent to 176.36 for the trading week ended Dec. 6. Decliners outpaced gainers 86 to 66, with eight companies unchanged.

The biggest mover was Puma Biotechnology Inc., soaring 77 percent to $86.75. The West L.A. cancer drug developer previewed clinical trial results for a breast cancer chemotherapy treatment.

OSI Systems Inc. fell 15 percent to $64.75. The biggest part of the drop came after the U.S. Transportation Security Administration canceled a $60 million order for the Hawthorne company’s airport screening machines.