Wednesday was a bad day for investors of Spectrum Pharmaceuticals as it toppled more than 35% due to a significant reduction of estimated sales of its flagship product, Fusilev. Generic leucovorin, which had been absent from the market started to return and materially affected orders for Spectrum's branded drug.

In this video, Motley Fool analyst David Williamson recaps the recent news and picks up the pieces for investors taking a look at the drugs in Spectrum's pipeline, including cancer drug Apaziquone, which it recently regained the rights to from Allergan.

Is Spectrum a buy at these new lower prices, or should investors proceed with caution? Watch and find out.