Heavy losses for CSL help drag ASX into the red

CSL suffered its worst loss in four months, falling 4.8 per cent to $290.24, and causing a 21.3-point drop in the ASX200, making it responsible for more than 70 per cent of the day's losses for the index.

The blood products giant announced Monday that a plasma-derived treatment it had spent two decades and almost $1 billion developing did not appear to prevent secondary heart attacks, as CSL had hoped.

The Australian dollar was buying 65.20 US cents, from 64.98 US cents at Friday's ASX close.