Alexion Pharmaceuticals (ALXN) is an extremely interesting title from the technical point of view, for his standard linear growth with few variations over the last three and a half years, period during which grew over 500%. Although this movement could be already a bit exhausted, the sky is the limit and it seems to be creating a repeating pattern.
In the last three times it reached a top, it ended up having a slight decline, followed by a breaking up for a new high. These downturns have led to a rising trend line of medium / long term. Despite not having many points of contact, has proved to be effective. Notice that, in each retraction volume decreased, increasing immediately afterwards, demonstrating a clear bullish signal.
There is currently doing a new retraction after a top, with gradually decreasing volume, and closer to the trend line.
It seems to me a clear buying opportunity, if it approaches to the trend line. Despite being a biotech, with all the inherent risks, the risk / benefit ratio is quite favorable!