"PFE recently paid $14 billion for Medivation which owned 50% of Enzalutamide which is the only drug that Medivation had on the market."

XTandi (enzalutamide) sales for 2nd quarter (before the buyout) were $595 million.  What MIGHT happen with a Zenith product somewhere down the road is not comparable to that.

"In July 2016 TBRA’s market cap went up to $1.5 billion on the news of a takeover offer by Allergan after a failed Phase II trial"

RVX went to 29.50 on rumours of a takeover.  Again, a takeover, or rumours of a takeover are not comparable to anything currently going on with Zenith.

"After I put it all together and stir the pot I come up with "my" valuation of $2 to $5 billion today as a Phase I company that has just started the combination part of their Phase I trial."

Then you'd have to explain why RVX in Phase III has a market cap of just ~$226 million.

(my bolding)