The company you mentioned (IFRX) and Amarin are not very comparable. IFRX market cap is only about 160 million. Daily volume is only around 280 million shares per day. Their PPS has been right around 6.50 for the last year. They did also make a presentation at the JP Morgan Conference that was recently held.
The only way to compare them is to say that either IFRX is extremely over valued, or AMRN is extremely under valued at their current share prices.