The Makalu report on Resverlogix had an interesting calculation on NPV.  He did it 3 different ways, and generally came to US$4 billion as a fair value, but Makalu assumed that Phase 3 would meet primary end points.

First, Makalu compared it to Humira, and asked what the right price would have to buy out Humira back in 2003, knowing what the future sales would be.  US$4 billion!  I find this still quite low, as Humira racked up $18 billion in sales in 2018 (with probably a 90% profit margin).

Second, Makalu compared Apabetalone to Amarin's Vascepa, and allowed for a discount (since Vascepa was already approved and in the market).  Amarin's enterprise value was US$6 billion, and it is a one trick pony with easy substitutes (cheaper fish oil), but with a potentially bigger market. By contrast, Apabetalone will be given to diabetic/low LDL/ACS hit patients (not counting off label use which IMHO will most likely outpace all current estimates).  So US$4 billion is a lower case approximation.  Again, I find this a bit low, as Apabetalone is going to see a Humira like future...with many more indications to be added, unlike our one trick pony comparable.

Third, Makalu does a DCF of future cash flows based on all 3 indications working.  The result once again is US$4 billion.  Frankly, I find this the weakest link in the US$4 billion valuation.  If we follow the Humira time line, this DCF is certain to be a huge underestimate.  That would be more in line with US$10 billion, IMHO, given many more indications to come.

So I think Don's claim of $4 to $8 billion is well within the fair valuation that you can get from 3 different ways of valuing RVX.