X4 Pharmaceuticals, Inc. Q4 FY2023 earnings call

Milestones Highlights - Submission and acceptance of NDA for mavorixafor for WHIM syndrome under FDA priority review, with PDUFA date April 30. - Positive safety and efficacy results from global pivotal Phase 3 trial in WHIM, with pending full results publication. - Progress in chronic neutropenia program: Phase 2 trial enrollment increased, with data update expected in H1 2024; finalized Phase 3 protocol for chronic neutropenia, planning to initiate in H1 2024. - Disease awareness campaign successful, increasing physician awareness of WHIM syndrome. - Plans for global approvals: potential EMA submission for mavorixafor in WHIM by late 2024/early 2025.### Financials - Raised over $87 million in 2023, ending 2023 with $115.2 million in cash and equivalents. - Discussed potential non-dilutive funding sources, priority review voucher for mavorixafor, and anticipated revenues from U.S. sales.

R&D expenses for the fourth quarter of 2023 were $15.3 million, compared to $19 million in the comparable period of 2022. Full-year 2023 R&D expenses were $72 million, versus $61.1 million in 2022. SG&A expenses for Q4 2023 were $9.9 million, down from $26.6 million in 2022. Full-year 2023 SG&A was $35.5 million, compared to $27 million in 2022. Net loss for Q4 2023 was $19.1 million, versus $29.1 million in 2022. Full-year 2023 net loss was $101.2 million, compared to $93.9 million in 2022.

Forward-Looking Statements - Funds raised in 2023 will support operations into 2025. - Optimistic about receiving a priority review voucher for mavorixafor due to rare pediatric disease designation. - Anticipate additional milestone-based debt through Hercules facility and revenues from U.S. sales of mavorixafor.

Q: Kristen Kluska asked about commercialization and chronic neutropenia, specifically monitoring and neutrophil measured protocols in commercial setting.

A: Dr. Paula Ragan mentioned excitement about pending Phase 2 data update, focus on monotherapy and combination data, and developing product to address patient range.

Q: Kristen Kluska asked about trends in physician awareness for WHIM syndrome.

A: Mark Baldry responded that disease awareness campaign highlights varied presentations of WHIM, dispelling the need for all four symptoms, leading physicians to realize they may have more WHIM patients.

Q: Ed Tenthoff asked about FDA manufacturing visits, labeling discussions, and salesforce cost.

A: Dr. Christophe Arbet-Engels said interactions with FDA are on track for PDUFA date, and Mark Baldry mentioned a fully trained rare disease field team will be deployed upon approval, with details to be shared post-approval.

Q: Sean Lee asked about patient outreach in awareness campaign.

A: Mark Baldry responded that they are building foundations for launch, targeting physicians, potential patients, and payers with education on WHIM burden and mavorixafor's value proposition.

Q: Stephen Willey asked about Phase 3 chronic neutropenia subtype representation and eligibility criteria.

A: Dr. Christophe Arbet-Engels said Phase 3 includes congenital, idiopathic, and autoimmune patients, with analysis of subtypes possible given sample size.

Q: Unidentified Analyst asked about GCSF dosing in chronic neutropenia Phase 2 and infection rate delta in Phase 3.

A: Dr. Paula Ragan addressed GCSF dosing being lower than labeled dose as standard of care, and Dr. Christophe Arbet-Engels mentioned aiming for a 40% difference in annualized infection rates in Phase 3 based on WHIM data.