X4 Pharmaceuticals Inc To Host Virtual Investor Event Transcript

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

Question: Kristen Kluska - Cantor Fitzgerald LP - Analyst : Hi. Good morning, everybody. Congrats on these data, and congrats that the launch is also going well in the background. So the first question I had for you, I think you made this important point that mavorixafor could reduce or replace. And I think there's been a lot of questions about what success would look like for reducing. So maybe for the management team and for Dr. Newburger, can you help us understand what degree of reducing G-CSF truly is meaningful from these patients, both from the burn in some of injections, but maybe more importantly, on reducing that bone pain and why this is so critical. Thank you.

Question: Kristen Kluska - Cantor Fitzgerald LP - Analyst : Thank you for that. Very helpful. And then for severe chronic neutropenia, what percent of that initial 15,000 patients you've laid out do you believe present with these dangerous levels at baseline? And anything in particular about their CN profiles that lead to such low neutrophil counts?

Question: Kristen Kluska - Cantor Fitzgerald LP - Analyst : Thank you. And if I may squeeze in one last question. Just on the 3 discontinuations, you noted that from your WHIM trial experience, that these effects of diarrhea and nausea really alleviate over time as they become more comfortable with the treatment. Can you remind us when you typically see some of these side effects go away and how this has been articulated in the conversations and education you've done with the patients, which has seemed to fix the problem for now? Thanks again.

Question: Edward Tenthoff - Piper Sandler Companies - Analyst : Hey. Good morning, everyone. It sounds like myself off video. Oh, no, it doesn't. Yeah. Hi, how are you? Thanks so much for taking the time today. And I had a question for Dr. Newburger. With the current data set in hand in neutropenia, how do you envision deploying mavorixafor? Specifically, without the prior written consent of Thomson Reuters. 'Thomson Reuters' and the Thomson Reuters logo are registered trademarks of Thomson Reuters and its affiliated companies. JUNE 27, 2024 / 12:00PM, XFOR.OQ - X4 Pharmaceuticals Inc To Host Virtual Investor Event do you think you would probably wean patients from G-CSF or would you discontinue outright? How do you envision sort of initially using this? And I guess for the company, I appreciate there's a small end, but are we seeing characteristics that may differentiate either biomarkers, early response or neutrophil levels that may indicate who would respond versus not responding? Thank you

Question: Edward Tenthoff - Piper Sandler Companies - Analyst : That's incredibly helpful. And if I may ask a quick follow-up question. For new patients who are chronic or idiopathic and not congenital, could you envision even starting straight out on mavorixafor and foregoing G-CSF? Thank you again, doctor. Peter Newburger - University of Massachusetts Chan Medical School and at Boston Children's Hospital - Pediatric Hematologist, Oncologist That would absolutely be my approach. Based on the Phase 1b and Phase 2 data, the response is detectable within the first day and certainly within the first few weeks to months. So that one would see very quickly whether it would be possible to continue with monotherapy with mavorixafor. I would bring in G-CSF only in those, I would expect to be a few patients who had an inadequate initial response.

Question: Leah Cann - Brookline Capital Markets LLC - Analyst : Thank you. My question has been answered. without the prior written consent of Thomson Reuters. 'Thomson Reuters' and the Thomson Reuters logo are registered trademarks of Thomson Reuters and its affiliated companies. JUNE 27, 2024 / 12:00PM, XFOR.OQ - X4 Pharmaceuticals Inc To Host Virtual Investor Event

Question: Ed Arce - H.C. Wainwright & Co - Analyst : Thank you. Thanks for this presentation and congratulations on the data. Certainly very, very interesting and encouraging. Looking at the monotherapy data that you presented and looking at the dynamics of the ANC increases over month one to month six, I'm just trying to understand the -- I'm just going by absolute values and maybe that's not the right way to do it, but just to understand. When it gets to month six, there's a decline in the increase on the ANC. Is this a factor of who the patients are within that three patients -- that group of Phase 3 patients? Or is there something else that we should be thinking about in terms of absolute value decline?

Question: Ed Arce - H.C. Wainwright & Co - Analyst : Thank you. And a quick question for Dr. Newburger. The split between the different types of patients that are currently in the trial, is that typical to what you see in your practice in terms of who the types of patients are that come into your plan? Peter Newburger - University of Massachusetts Chan Medical School and at Boston Children's Hospital - Pediatric Hematologist, Oncologist No, I think the trial probably purposely included more patients with congenital neutropenia, whereas in practice, the very, very large majority of patients have idiopathic autoimmune neutropenia. This is true both in pediatric and in particular, even more so in the adult population.

Question: Kalpit Patel - B. Riley Financial Inc - Analyst : Yeah, hey. Good morning. Thanks for taking the questions. Maybe two for the company. Have you guys analyzed the infection before and after rates? I know this is open label. We have limited follow up so far. But are there any early indicators that the infection rates are trending lower in the patients who have at least six months of follow-up?

Question: Kalpit Patel - B. Riley Financial Inc - Analyst : Okay. Fair enough. And will we get additional data for the patients that are still on therapy later in the year for both the monotherapy and the combination therapy arms that we don't have six-month data for?

Question: Kalpit Patel - B. Riley Financial Inc - Analyst : Okay. One last question, maybe this one is for KOL. Doctor, what do you think about the Phase 3 trial design and its potential applicability for the real world? One of the pushbacks that we get or we have gotten is that the study is requiring a stable dose of G-CSF if a patient is on background

Question: Kalpit Patel - B. Riley Financial Inc - Analyst : Okay. Thank you very much for taking my questions.

Question: Dan Ferry - LifeSci Advisors - Analyst : Thank you. So Paula, a couple of written questions here from the audience. The first would be, what are some other rare diseases that could see a benefit from raising neutrophil levels? And will X4 be able to tap into these? And then as a follow-up question, how are current partnerships going for ex-US and that potential to expand worldwide?

Question: Dan Ferry - LifeSci Advisors - Analyst : Okay, great. All right, Paula, it looks like we have time for one more question here. This question pertains to the Phase 3. It took months to get 15 patients. How long will it take to find 150 patients for the Phase 3?