In the following video, Motley Fool health-care analyst David Williamson continues his look at the top-performing health-care stocks of this past January, by highlighting the biggest winner of the month, Keryx (NASDAQ:KERX). The stock exploded this month, shooting up 247%, although David reminds us that this was possible only because of the stock's starting point after the share price collapsed last year, when a cancer drug it shared with Aeterna Zentaris (NASDAQ:AEZS) failed its phase 3 trial. David tells us about the new drug in Keryx's pipeline that is crushing its trial endpoints, and how the new drug compares with its competition.

David Williamson and The Motley Fool have no position in any of the stocks mentioned. Try any of our Foolish newsletter services free for 30 days. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.