Enanta Pharmaceuticals Inc (ENTA)

[willyw]

Let’s use the HCV market as a comparator

This makes very good sense to me- in a very general sense.
For broad strokes its as good as any way to ballpark sales.

annual size of the addressable market for an HBV-curing regimen will be comparable to what it was for HCV.

Again- I agree. But given general agreement I would be inclined to guess less. As you say correctly many of the countries have less money.
Interesting to me that Gilead was threatened with patents; both by India, but ALSO by rights to patents in earlier drug development. Might Enta experience the same OR can it sidestep that? (India and other countries subsequently eroded the Gilead's power over it's pricing.)

The peak-sales year for HCV

Rather than quoting the entire passage I have to note that there is only so much pie.
Right now HCV is still being funded.
There are also massive covid relief bills still planned against the backdrop of covid AND global warming.

For ENTA, specifically, an important question is what proportion of the total HBV functional-cure market will be comprised of all-oral regimens, assuming that an all-oral regimen exists. I would submit that this proportion will likely be at least 50%.

Like HCV there may be a few winners.
But often the first doesn't stay first place; example Gilead w/ HCV- but they made so much money simply being first.
In the case of Harvoni vrs Mavyret for instance the efficacy is quite close- so Gilead has benefited close to equally even in long term.

It's too early to actually be able to compare all HBV programs, but my sense is that Enanta may not have any close competitors;

1) I cannot think of a efficacious all oral program equally ENTA's.

2) Many are oral AND injectable.
COMPARE to ENTA's all oral.

3) Assuming it takes 3 compounds I'm not sure that any one company possesses all the requisite drugs -such as ENTA may have.
- Enanta- in possessing 2 of the 3 (the third being an existing nuke), was able to optimize the two drugs to work together and WITH the existing nuke. MANY collaborations may have decent drugs but they simply must be thrown together without that initial planning and optimizing. If they happen to be a perfect match it may be a fluke.

AND SO.... there may be temporary decent therapies (think early HCV; telaprevir, boceprevir, simeprevir) but none of these were the ultimate- even to some extent Gilead Harvoni was to ultimately take 2nd place.
I think there is a strong question as top whether other companies will be able to unseat the ENTA HBV program.
I admit- it's way, way early.
But many MANY large juggernaut companies were NOT able to produce what ENTA did- not once but twice in HCV.

So where I was a little stingy on annual spending on HBV, I wonder if Enanta could end up with a larger than half HBV share.
I wonder how much warehousing may occur?

I think I agree with you generally.
I think that the devil is in the details in development and distribution.
The drug development may have been the easy part. : )