argenx SE (NASDAQ:ARGX) Q4 2022 Earnings Call Transcript

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Keith Woods: Yes. So the data that I quoted in the prepared remarks are the first to second dose and it really shows a nice distribution about a third, a third, a third. I want to call out that that interval is after the last dose of the first cycle. So when we have about a third of patients that are going nine weeks and some substantially longer than that just like we saw in the ADAPT trial. We haven’t been public with any data on real world on between second and third. But as you might recall from the past, we’ve referenced that From the ADAPT, OLE study, you can typically see that when a patient gets in their individualized cadence, so if they become a nine week interval between the last dose of one cycle and the first dose of the next one, that cadence typically holds standard and once they get dialed in, it just becomes their regularly scheduled dosing.

So although we haven’t been public with something between second and third. Right now, I’m not expecting a major change except for maybe some of those patients that went with shorter interval to see if there isn’t an opportunity to stretch a little further.

Tim Van Hauwermeiren: Thank you, Keith. And then on the PRV, we continue to understand our options, but technically speaking, guys, we’re still in a priority review and we decided to take a forward looking approach with the FDA and try to collaborate as swiftly and expedited as possibly towards the PDUFA date? Thank you for the question.

Operator: Your next question comes from the line of Danielle Brill from Raymond James. Your line is open.

Alex Nackenoff: Hey, guys. This is Alex on for Danielle. Just another one on CIDP. We had a few questions come our way. Just when did you decide to increase the enrollment? And what information, if any, did you have in hand that aided your decision to upsize or was this just an organic strategic decision? Thanks.

Tim Van Hauwermeiren: Well, thank you for this question Alex. There was not a distinct point in time where we decided to increase enrollment. We decided to just not stop enrollment and continue to enroll. And the reason is that, it would be pity for those patients who all have an opportunity to come on drug not to do that, because not all of them, of course, are going to make it to the end of Stage B, but all of these patients would then have the opportunity to roll over to the open label extension and also contribute to the safety database. Remember, in the background, not only do we need to build efficacy data, but also strong files, strong evidence of safety. So it was a decision not to stop rather than to a large history . Thank you.

Alex Nackenoff: Great. Thanks.

Operator: Your next question comes from the line of Allison Bratzel from Piper Sandler. Your line is open.

Allison Bratzel: Hi, good morning. Thanks for taking my question. Just another one ADHERE. It seems like a lot of focus has been placed on the relapse rate in Stage B. I guess, it’s our understanding the endpoint is actually time to relapse rather than a percent of patients relapsing at a given time point. So my question is, what is the actual metric we should expect to see from Stage B? Is that going to be communicated as a hazard ratio median time to relapse something else? And just in that case, would you look to the hazard ratio from past as the best comp? And then just related, will you have actual relapse rate data and time for the top line readout, just given that a bunch of patients may not have made it to the end of Stage B by the time the event has occurred. Thanks.

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