X4 Pharmaceuticals, Inc.

Greetings and welcome to X4 Pharmaceuticals' third quarter financial and operating results conference call. At this time, all participants are in a listen-only mode. The question and answer session will follow the formal presentation. As a reminder, this conference call is being recorded. It is now my pleasure to introduce your host, Candice Ellis, Director of Corporate Communications and Investor Relations at X4. You may begin.

Thank you, Operator, and good morning, everyone. Thanks so much for joining us today. Presenting on today's call will be our Chief Executive Officer, Dr. Paula Reagan, and our Chief Financial Officer, Adam Mostafa. Following prepared remarks by each, we will open the call to your questions, and they will be joined by our Senior Vice President of Technical Operations and Quality, Dr. Mary DiBiase. As a reminder, on today's call, we'll be making forward-looking statements regarding our regulatory and product development plans, as well as our research activities. These statements are subject to risks and uncertainties that may cause actual results to differ from those forecasted. Descriptions of these risks can be found in our most recent Form 10-K, on file with the SEC, and our forthcoming Form 10-Q. I'd now like to turn the call over to our CEO, Paula Reagan.

Thanks, Candice, and thank you, everyone, for joining us on the call this morning. We hope you are all continuing to stay safe and healthy. We are pleased to report today that while the operating environment remains challenging due to the ongoing COVID-19 pandemic, we continue to advance our Mavericks IV clinical development programs. Let me begin with a review of our most recent accomplishments. We are pleased to announce the publication of our positive Phase II safety and efficacy data for Mavericks IV and WIM syndrome in the prestigious journal Blood, which we believe further recognizes the significant potential of our lead candidate in this patient population. As a reminder, WIMP syndrome is a rare inherited primary immunodeficiency disease caused by mutations in the chemokine receptor CXCR4, a receptor that plays a key role in enabling the healthy trafficking of immune cells and effective immunosurveillance. MAVIRISTA4 is our first-in-class small molecule antagonist of the chemokine receptor CXCR4, and it's being developed as a once-daily oral therapy. While the comprehensive data published in blood expands on previously presented data, there were new results presented, including patient-level data regarding the specific effects on neutrophils, lymphocytes, and monocytes, as well as the effect of increasing doses of maverixifor on total white blood cell counts. In addition, the manuscript provided the most up-to-date long-term safety and pharmacokinetic data and presented a detailed analysis of the clinical benefit of the extended Maverick Sephora therapy on infection rates and warp burden. This important publication in the official journal of the American Society of Kematology provides key third-party validation of the data supporting our clinical strategy, including the selection of the dose, primary biomarker endpoints, and secondary clinical endpoints for our ongoing pivotal Phase III clinical trial. The published results continue to reinforce our belief that by down-regulating the CXCR4-CXCL12 signaling pathway, Mavrixivor has the potential to be the first disease-modifying therapy for the more than 3,500 estimated diagnosed and undiagnosed WIM patients in the U.S. We are also thrilled to be granted FAST-TRACK designation by the FDA for Maverick Spore and WHIM syndrome. Through the FAST-TRACK program, X4 is eligible for more frequent meetings with the FDA to discuss the drug development plan, protocols, and clinical data that would support Maverick Spore's potential approval for WHIM. This key regulatory achievement further recognizes the significant unmet need of WHIM syndrome and Maverick Spore's potential to treat this challenging disease. As a reminder, Maverick Sephora was previously granted breakthrough therapy designation by the FDA, as well as orphan drug status by the FDA and the European Commission for the Treatment of Wim Syndrome. Let me now provide an update on our ongoing clinical development programs for Maverick Sephora. Importantly, despite continued uncertainties surrounding COVID-19, we remain focused on advancing our clinical development programs. We continue to enroll patients in our Phase III WHIM syndrome trial and make good progress across the various regulatory and clinical aspects of the trial. We are diversified across numerous sites and countries around the world, each of which has its own regional and site-level COVID-19 considerations. We are working with the sites to maintain enrollment momentum in the trial and including additional services, such as in-home patient visits, to mitigate the impact of COVID-19. We continue to anticipate top-line Phase III data in WHIM syndrome in 2022 and intend to provide further clarity on the timeline as soon as we are able to do so. Our Phase I D-trial in severe congenital neutropenia also continues to make progress, and we anticipate initial data from this 14-day proof-of-concept study in 2021. Similar to the Phase III WIM syndrome trial, we intend to provide further clarity around our SBN trial timeline as soon as we are able to do so. In Waldenstrom's macroglobulinemia, or WM, a rare form of lymphoma, we are continuing to enroll patients, although COVID-19-related delays have had some impact, as we recently disclosed. We expect the availability of the initial Phase Ib clinical results in the first half of next year, a slight delay from our previous guidance of the second half of this year. In order to mitigate COVID-19-related patient travel concerns in the study, we are focused on implementing home health visits. We are in regular dialogue with our investigators and through our patient advocacy team with patients to understand their needs given the extended challenges of the COVID pandemic. We are confident that we have an effective plan in place to appropriately address the impact of COVID-19 on our WM study. As a reminder, this Phase Ib clinical trial is expected to enroll between 12 and 18 patients with WM and is a multicenter, open-label, dose-escalation clinical trial assessing the safety and tolerability of Maverick's spore in combination with ibrutinib. The trial is being conducted as part of a collaboration with the Leukemia and Lymphoma Society to accelerate the development of Maverick's spore for the treatment of Waldenstrom's. The results of this study will share safety and dose escalation data and important efficacy signals, and we expect that these data will inform future FDA discussions regarding the potential registration trial in WM. Lastly, I would like to welcome two new additions to the X4 leadership team. Dr. Art Tavares started earlier this week as our new chief scientific officer. Art is an experienced CSO who is joining us from Co-Met Therapeutics, a privately held company focused on coenzyme A science and intermediate metabolism, where he also served as CSO. Prior to his role at Co-Met, he founded and was chief scientific officer of Transform Therapeutics, where he led the discovery of a novel next generation CXCR2 antagonist for the treatment of cancer. In addition, Art held key leadership roles in drug discovery at Biogen and at Shearing Plow earlier in his career. With his significant expertise in chemokine-related chemistries, decades of drug discovery experience, and inspiring leadership, Art is an ideal fit to lead our R&D initiatives and further foster our evolution towards becoming a global rare disease company. In addition, we recently expanded our board of directors with the appointment of Allison Lawton, an industry veteran who strengthens our board's expertise across many strategic fronts. Ms. Lawton most recently served as CEO of Kaleido Biosciences and having previously served as a consulting chief operating officer to the company and as a member of X4's corporate advisory board. Allison brings a unique understanding of X4's core scientific and corporate goals. I look forward to working closely with her again. With that, I'll now turn the call over to Adam to discuss our financial results for the quarter. Adam?