Replies to post #2955 on Enanta Pharmaceuticals Inc (ENTA)

[dewophile]

Liisa Bayko, EVR.

Hi, this is Tina on for Lisa. And I have a question on the 323 program. What doses of two three are you testing in Phase IIa human challenge study?

Jay Luly

Yes, so we're looking at a couple of different dose regimens. So the first it's 600 milligrams straight across for five days. And the other is 600 milligram loading dose on day one, followed by 200 milligrams on each subsequent day.

Assuming the absorption of edp-323 is comparable to edp-938 you are looking at several orders of magnitude higher multiples of virologic inhibition with the newer RSV candidate since it has been described as having much greater potency than 938 (picomolar and subnanomolar vs nanomolar). Dose of 938 is 800mg a day.
I'm assuming this is why this question was asked. I kind of felt the company may be wasting resources on yet another RSV drug since the patients that would benefit from a combination of the two would tough to tease out, but now I am starting to get why they continued development - they were pretty far along anyway, it might actually be better based on this dosing and profile, and you want to stay a step ahead of competition.

same analyst asked this:

I had second question on the patent against the case against Pfizer because loss created by this setback exclusive, it doesn't infringe the patent because it has high floral growth, which is not described in York PATTY. So if you can comment on that?

I think she was referring to the trifluoral group on paxlovid. I haven't followed the PFE calls and had no idea they had been so specific about the patent case with analysts in the past. I can't really speak to this at all - perahps one of the lawyers can chime in - but it seems poor form IMO to comment so specifically on ongoing litigation. I did google the term and found this referencing the patent:

https://www.linkedin.com/pulse/wondering-what-pfizer-wants-specifically-enumerated

Support for R15 as fluorine substituted tert-butyl is found specifically in the specification in column 69, lines 61-64: “The term “substituted” refers to substitution by independent replacement of one, two, or three or more of the hydrogen atoms with substituents including, but not limited to, —F, —Cl, —Br, —I, —OH, …”

Also, the following text in specification in column 7, lines 45-48: “Preferably, A has 0, 1 or 2 substituents.Preferably the substituents are independently selected from fluoro, chloro, hydroxy, methoxy, fluoromethoxy, difluoromethoxy, and trifluoromethoxy” clearly implies the intention of the A group having trifluoromethoxy.

So seems if the ENTA patent holds up it does indeed cover fluoro/ trifluoro groups