Amylyx Pharmaceuticals Inc Q2 2023 Earnings Call Transcript

The following is excerpted from the question-and-answer section of the transcript.

Question: Ananda Kumar Ghosh - H.C. Wainwright & Co, LLC, Research Division - Analyst : Congrats on the quarter. So I have 2 questions on the ALS program and one for the PSP. The first question is basically some of the question which keeps coming from the industrial community, and that would be if PHOENIX is a required confirmatory study for accelerated approval of RELYVRIO and what -- if it says, then can FDA initiate a process to pull it off from the market? So any clarification on that would be great. And then I have a follow-up question on the ALS program and then a PSP. Justin B. Klee - Amylyx Pharmaceuticals, Inc. - Co-Founder, Co-CEO & Director Sure, and thank you for the question, Ananda. And yes, I mean, first, there is a full FDA approval. There's no condition of the PHOENIX study. In Canada, it's an NOCC, which means a Noticing Compliance with Conditions. And again, our expectation in Europe if there's an approval, is that it would also be a conditional marketing authorization, and the condition there would be PHOENIX. So we continue to run the PHOENIX study. We'll have those results mid- next year. That's a very highly powered study. And we and I think the ALS community are looking forward to those results. But from an FDA perspective, it's a full FDA approval.

Question: Ananda Kumar Ghosh - H.C. Wainwright & Co, LLC, Research Division - Analyst : Right. And my last question is on PSP. Based on some natural history data, so we kind of saw that the PSP studies in general has couple of disadvantages. One is a very high rate of dropouts. And some of the scales to say cognition and depression mostly fails, at least in the historical PSP trials. So what has been your thought on it? And how have you kind of incorporated these into your Phase III trial design? Joshua B. Cohen - Amylyx Pharmaceuticals, Inc. - Co-Founder, Co-CEO & Director Yes. So we shared and probably even more importantly, Prof. Dr. Gnnter H÷glinger shared on a recent call that we did that's published on our website a much more in-depth view of PSP and our upcoming clinical trial. So in our PSP trial, we are designing the study based on the PSPRF, the PSP rating scale. This is a scale that tracks primarily -- I would say, primarily kind of motor and functional rather than cognitive outcomes of PSP. The PSP rating scale studied in several past trials, what's been found quite consistently is an approximate 10-point progression over approximately a year with a pretty small error and a pretty tight kind of variance when you're in these studies. Dropout is not in our view and has not been in previous studies beyond what you might have in other neurodegenerative diseases. And again, as has been shown from the previous studies, this is a space actually where the power is quite good compared to most neurodegenerative diseases. So I'd say overall -- and again, I encourage people to listen to the webinar where we go into this in a lot more detail. But I'd say overall, we feel very strongly that we have a great trial design, we have a great scientific rationale, and this is a great indication to take AMX0035 into.