Moleculin Biotech, Inc. (NASDAQ:MBRX) Q1 2023 Earnings Call Transcript

Jonathan Aschoff: Right. And if (ph) looks the way you wish, which is the primary endpoint, which is what I was talking about, is it the case where OS could trump that, and bring a good-looking PFS down in relevance if the OS was unimpressive or is PFS standalone okay for registration?

John Paul Waymack: My answer is that’s going to be date-dependent — data-driven, it will depend on what the data show. Certainly, we would like for both of them to be great. But if progress-free survival is adequate just by approval, then we would go to FDA with just that. And you always said, when you file an NDA, you give a four-month safety update, roughly, to the NDA while the FDA is reviewing. And for this type of trial, frequently the four-month safety update, if you didn’t have overall survival when you filed, you will in the safety update.

Jonathan Aschoff: That’s helpful. Thank you, guys.

Walter Klemp: Thanks, Jonathan.

Operator: Thank you. The next question is coming from Jeff Jones from Oppenheimer. Your line is now live.

Jeff Jones: Thanks, guys. Good morning, and thanks for taking the question. I guess two questions. In terms of the number of patients who are enrolled who are already above the lifetime maximum for docs, what does that look like in both the AML and STS studies? And then, in terms of AML, what is the plan for dialogue with the FDA on that front so you can explore the U.S. beyond the —

Walter Klemp: Sure, and thanks for the question. I’m going to defer to Jon as the keeper of the headcount data. But while he’s maybe looking for that specific point, a couple of comments. One, among the people that we’ve taken above the lifetime maximum, it’s now getting to be a pretty substantial number. We’ve had a few of those people reach as high as 1,800 mgs per square meter, and whereas the lifetime maximum is 550. And so, we’re not just taking them slightly over that threshold; dramatically over that threshold. And historical data supports that 65% of all patients that are taken above the 550 lifetime maximum will exhibit some evidence of cardiotoxicity. And again, in our case, 100% of them have exhibited no evidence of cardiotoxicity. So, we’re pretty proud of the track record here. Jon, do you have a current count on the total number of people that have been taken over that limit?

Jonathan Foster: No, not anything updated, that’s currently out on our — beyond what’s on our corporate dash, I think the last number of 18. I would just tell you from a standpoint with this — both trials moving so quickly, we really don’t want to report on that till that data has been audited and confirmed.

Jeff Jones: Understood.

Walter Klemp: And what was the second part of your question?

Jeff Jones: The second question was on AML and discussions with the U.S. FDA?

Walter Klemp: Discussion with the FDA, sure. Paul, do you mind characterizing how you feel like that FDA discussion on AML would need to go?

John Paul Waymack: Yes. Well, first, just to remind everybody. This trial is unblended, everybody gets the drug. So, we see the data in real-time. And we’re obviously not going to go meet with them after a dose escalation, it would be after the expansion cohort. So, we would be watching to see what affect we’re having in the expanded cohort, which won’t start until sometime later this year. We would meet with FDA when we see enough efficacy, both in terms of the magnitude of it and as far as talking about the statistical confidence intervals in the data where we think we have established that this drug works for AML and combination therapy. As Wally mentioned, right now, recently, once we’ve gotten this drug up to around 200 or more milligrams per meter square, we’re getting about a 50% complete response rate.