MACROGENICS INC Q1 FY2024 earnings call

• Clinical Programs: Discussed the TAMARACK Phase II study of vobramitamab duocarmazine (vobra duo) in metastatic castration-resistant prostate cancer (mCRPC), with updated interim data on PSA50 responses, disease control rates, and safety. Also provided updates on MGC026 Phase I dose escalation, enoblituzumab investigator-sponsored study, lorigerlimab LORIKEET study, and MGC028 preclinical data.
• TAMARACK Study: Vobra duo evaluated in 2 mg/kg and 2.7 mg/kg arms; interim data showed PSA50 responses, disease control rates, and improved safety vs. Phase I. No clear B7-H3 expression threshold for PSA reduction.
• Other Programs: MGC026 is a complementary B7-H3 ADC with promising preclinical data; enoblituzumab in investigator-sponsored Phase II study; lorigerlimab in LORIKEET study and combination with vobra duo; MGC028 preclinical data supports IND submission by end of 2024.

MacroGenics reported total revenue of $9.1 million for the quarter ended March 31, 2024, down from $24.5 million in Q1 2023. The decrease was mainly due to a reduction in collaborative and other agreements, including a $15 million milestone from Incyte in Q1 2023. Research and development expenses were $46 million in Q1 2024 vs. $45.9 million in Q1 2023. Selling, general, and administrative expenses were $14.7 million in Q1 2024 vs. $13.5 million in Q1 2023, driven by increased stock-based compensation and consulting fees. Net loss was $52.2 million in Q1 2024 vs. $38 million in Q1 2023. Cash, cash equivalents, and marketable securities balance was $184.2 million as of March 31, 2024, down from $229.8 million as of December 31, 2023, but expected to provide cash runway into 2026.

• Anticipate cash runway into 2026 based on $184.2 million cash balance as of March 31, 2024, and projected future payments.
• Plan to share updated TAMARACK data in second half of 2024, including rPFS.
• Expect to initiate dosing in additional TAMARACK cohorts (non-small cell lung cancer, etc.) in mid-2024.
• Aim to submit IND for MGC028 by end of 2024.

• Potential lack of correlation between B7-H3 expression and efficacy.
• Ongoing investigation of causes of Grade 5 events like pneumonitis and pleural effusion.
• Uncertainty in cause and effect of adverse events, including pneumonitis and pleural effusion.
• Variability in patient responses and potential for unconfirmed responses to mature over time.

Q: Elaborate on safety improvements vs. Phase I study A: Discontinuations and Grade 3 events are better than Phase I, comparing favorably to other prostate cancer studies Q: Pneumonitis occurrence and B7-H3 expression A: Pneumonitis cases under investigation; no clear B7-H3 expression in lungs Q: Efficacy and B7-H3 expression correlation A: No clear correlation observed, suggesting B7-H3 biomarker may not be required Q: Combination use of vobra duo A: Interested in combining with lorigerlimab and other agents, with plans for dose expansion studies Q: Durability of responses A: Encouraged by high percentage of patients still on therapy, expecting further maturation of data