Financial Data and Key Metrics Changes - At the end of 2024, the company reported cash, cash equivalents, and marketable securities totaling $134.6 million, which is expected to support operations into 2026 [16] - Net cash used in operating activities for Q4 2024 was $19.3 million, a significant decrease from $32 million in the same quarter of 2023 [16] - Collaboration revenue for Q4 2024 was $16.4 million, up from $10.7 million in Q4 2023, primarily due to increased revenue from collaborations with J&J, Merck, and GSK [17] - Research and development expenses for Q4 2024 were $22.3 million, slightly up from $21.5 million in Q4 2023, with $1.7 million attributed to non-cash stock-based compensation [18] - General and administrative expenses decreased to $8.9 million in Q4 2024 from $10.1 million in Q4 2023, reflecting reduced employee compensation and consulting fees [18] - The net loss for Q4 2024 was $14.1 million, compared to a net loss of $19.5 million in Q4 2023 [18] Business Line Data and Key Metrics Changes - The lead ADC, Emily, reported a confirmed objective response rate (ORR) of 23% across all tumor types with high B7H4 expression, defined as an IHC score of 70% or more [7][9] - The expansion portion of the trial for Emily was initiated for patients with triple-negative breast cancer (TNBC) who have previously been treated with at least one TOPO1 ADC [8] - The company is exploring doses up to 95 mg/m² for Emily, with the top dose of 67.4 mg/m² being well tolerated in the expansion cohort [14][51] Market Data and Key Metrics Changes - The competitive landscape for B7H4 ADCs has shifted favorably for Emily, as a primary competitor, Pfizer, discontinued its B7H4 ADC candidate [12][40] - The company believes it is well-positioned in the B7H4 ADC space, being the most advanced in clinical development with positive efficacy data in the post-TOPO breast cancer setting [40] Company Strategy and Development Direction - The company is focused on advancing its lead candidates, Emily and XMT-2056, with ongoing clinical trials and collaborations [15] - There is an emphasis on the potential for Emily to be used in combination with standard care treatments, such as platinum chemotherapy, due to its favorable safety profile [41] - The company is also exploring additional indications for Emily beyond TNBC, given the clinical activity observed across various tumor types [13] Management's Comments on Operating Environment and Future Outlook - Management expressed confidence in the clinical activity of Emily, particularly in a high unmet need population of TNBC patients [8] - The company is optimistic about its cash runway and operational plans, expecting to support its commitments into 2026 without relying on future milestone payments [16] - Management highlighted the importance of ongoing investigator interest and engagement in their clinical studies [13] Other Important Information - The company has made progress in its collaborations with J&J and Merck KGa, which are expected to contribute to its research and development efforts [15] - The company has amended its clinical trial protocol to mitigate proteinuria issues observed at higher doses of Emily [14][22] Q&A Session Summary Question: Progress on mitigating AST elevation and proteinuria related to Emily - Management indicated that AST elevation does not lead to meaningful dose delays and is a transient, reversible phenomenon [21] - For proteinuria, mitigation strategies such as ACE inhibitors are being implemented, allowing for dose reductions instead of delays [23] Question: Distribution of patients with prior lines of therapy in the expansion cohort - Management stated it is too early to determine the distribution of patients with fewer prior lines of therapy, but confirmed that patients with more than four prior lines are excluded [29] Question: Establishing the final biomarker cutoff for B7H4 high - Management expects the TPS score to capture roughly 40% to 50% of the TNBC population [34] Question: Competitive landscape and Pfizer's discontinuation - Management noted that the discontinuation of Pfizer's program has led to increased interest in their study, positioning Emily favorably in the market [54]