Replies to post #225837 on Biotech Values

[DewDiligence]

ENTA—Why can't RSV development go faster?

RSV trial protocols are tricky with respect to dosing and scheduling. For instance, what should be the maximum allowable elapsed time from the appearance of symptoms to the administration of the first dose? If the maximum elapsed time is too short, enrollment will be adversely affected; if it’s too long, efficacy may be severely compromised.

Another issue is whether to use a loading dose. In the phase-2a “challenge” study, ENTA had arms with and without a loading dose, and they performed roughly the same, making this decision a tough call.

There have to be plenty of potential trial participants…

The planned phase-2b trial will be in immunocompromised adults, so the availability of patients may not be as large as you thought. Moreover, RSV is a seasonal virus; this doesn’t matter in a “challenge” study such as the completed phase-2a, but it does mater in a “real world” study such as the planned phase-2b.

…the economic case for 938 should be easy to make if it can reduce hospitalization in a meaningful way.

Agreed.

Looking forward to NASH results, although they are only measuring ALT. Can you remind me why they went from NAFLD to NASH for P2?

The intention from the start has been to pursue NASH; #msg-130609791 explains why the EDP-305 phase-1b trial tested patients with presumed NAFLD.

Good questions.