UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2025 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from _____ to _____ ARCELLX, INC. Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securitie ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): August 07, 2025 Registrant's Telephone Number, Including Area Code: 240 327-0630 Not Applicable (Former Name or Former Address, if Changed Since Last Report) Arcellx, Inc. (Exact name of Registrant as Specified in Its Charter) (State or Other Jurisdiction of Incorporation) Delaware 001-41259 47 ...

Company Overview - Arcellx, Inc. (NASDAQ: ACLX) is advancing its lead CAR-T cell therapy, anitocabtagene Autoleucel (anito-cel), aimed at treating patients with relapsed/refractory multiple myeloma (r/r MM) [2] Industry Insights - The article highlights the importance of deep-dive analysis in the pharmaceutical sector, particularly for investors interested in biotech companies [2]

Anito-cel Product Profile and Clinical Data - Anito-cel, a BCMA-directed CAR T-cell therapy, utilizes a novel D-Domain binder, potentially offering a best-in-class efficacy profile, differentiated safety, and rapid manufacturing[7, 8, 9, 15] - Phase 1 data showed a median Progression-Free Survival (PFS) of 30.2 months[17] - In the iMMagine-1 pivotal trial, the Overall Response Rate (ORR) was 97%, with a stringent Complete Response/Complete Response (sCR/CR) rate of 68%[92] - iMMagine-1 demonstrated a 6-month PFS rate of 91.9% and a 12-month PFS rate of 79.3%[98] - iMMagine-1 showed a favorable safety profile, with 85% of patients experiencing < Grade 1 Cytokine Release Syndrome (CRS) and 92% experiencing no Immune Effector Cell-associated Neurotoxicity Syndrome (ICANS)[17, 108, 118] Market Opportunity and Commercial Strategy - The Multiple Myeloma (MM) CAR T market is projected to reach approximately $12 billion in the 2L+ setting[7, 19, 21, 55, 61] - Arcellx anticipates a high gross margin of ≥70% at launch for anito-cel, with profitability achievable before reaching $1 billion in anito-cel sales[51, 55] - Post-approval, 90% of US Healthcare Professionals (HCPs) are motivated to prescribe anito-cel[30] - Anito-cel is expected to launch with a large Authorized Treatment Center (ATC) network, projected to be 160+ ATCs, leveraging Kite's infrastructure[17, 33, 62] - Payer coverage for anito-cel is projected to be >80% of US lives within 30 days and >90% within 90 days post-launch[45]

Summary of Arcellx (ACLX) Investor Relations Event - June 13, 2025 Company Overview - **Company**: Arcellx (ACLX) - **Event**: Investor Relations event held in Milan - **Focus**: Development of a novel cell therapy, Anitosel, targeting multiple myeloma Key Industry Insights - **Market Size**: - The second line plus market for multiple myeloma is estimated at **$12 billion** - The frontline market is projected to reach **$20 billion** - The fourth line plus population is approximately **$3.5 billion** [7][8][9] - **Market Research**: - Conducted with over **300 hematologists and oncologists** to assess market share and therapy adoption [11] - Anitosel is expected to capture a **58% market share** in 2024, increasing to **83%** in 2025 [12][13] Product Development and Clinical Trials - **Anitosel**: - A novel synthetic binder developed to address limitations of biologic-based binders, focusing on safety, scale, and manufacturability [5][6] - Strong clinical data in relapsed and refractory myeloma populations [6] - **IMMAGINE-one Study**: - Phase 2 study with **129 patients** enrolled, showing a **97% overall response rate** and **68% complete response rate** [31][33] - Median progression-free survival (PFS) of **30.2 months** and no delayed neurotoxicities reported [32][39] Launch Strategy - **Launch Timeline**: Anticipated launch of Anitosel in the U.S. in **mid to late 2026** [5] - **Market Access**: - Plans to access **80% of covered lives** within **30 days** of launch and **90% within 90 days** [21][22] - **Manufacturing Capacity**: - Expected to cover the majority of the fourth line plus population at launch, with a global potential of over **24,000 doses** [17][19] Operational Excellence - **Turnaround Time**: Expected turnaround time for Anitosel is less than **17 days**, with a high in-spec rate of **96%** [18][19] - **Partnership with Kite**: - Collaboration with Kite to leverage their expertise in cell therapy, enhancing operational efficiency and reducing costs [24][21] Financial Outlook - **Profitability**: Expected gross margins of **≥70%** at launch, with profitability anticipated at less than **$1 billion** in Anitosel sales [23][24] - **Capital Management**: As of Q1, the company has **$565 million** remaining on its balance sheet, reflecting operational efficiency [23] Safety and Efficacy - **Safety Profile**: - Anitosel demonstrated a predictable and manageable safety profile with no delayed neurotoxicities observed [39][40] - **85%** of patients experienced grade one or less cytokine release syndrome (CRS) [36] Conclusion - **Market Positioning**: Anitosel is positioned to be a leading CAR T therapy in the myeloma space, with a strong focus on patient safety, operational excellence, and market access strategies [28][29]

Summary of the Conference Call Company and Industry - The conference call involved **Arcelix**, a company in the **biotechnology** sector, specifically focusing on therapies for **multiple myeloma**. Core Points and Arguments 1. **Data Release and Efficacy**: Arcelix presented data from their **IMGIGINE-one** registrational trial, highlighting a **68% complete response rate** with a median follow-up of **12.5 months**. This positions their therapy, **anitosella**, as a leading option in the myeloma community [5][7][8]. 2. **Safety Profile**: The company emphasized that no cases of delayed events, such as **Parkinsonism** or **enterocolitis**, have been observed, suggesting a superior safety profile compared to competitors like **Carvicti** [8][9][16]. 3. **Manufacturing and Scalability**: Kite is responsible for manufacturing, and the company is confident in their ability to deliver the product reliably and at scale, with manufacturing times within the commercial specifications of **14 to 17 days** [41][42]. 4. **Regulatory Filing Timeline**: Arcelix aims for a **BLA filing** by mid to late **2026**, with productive discussions with the FDA ongoing [36][39]. 5. **Market Positioning**: The company plans to differentiate its launch strategy from previous CAR T therapies by ensuring better availability and reliability, addressing physician concerns about therapy access [43][44]. Additional Important Content 1. **Comparison with Competitors**: The company believes that the safety and efficacy data do not support the notion of a class effect among CAR T therapies, indicating that their product is distinct [9][19][31]. 2. **Patient Enrollment Challenges**: It was noted that excluding patients with peripheral neuropathy from trials would be impractical, as a significant percentage of patients experience this condition post-treatment [24]. 3. **ALC Monitoring**: The company does not monitor **Absolute Lymphocyte Count (ALC)** as a treatment intervention but captures it for analysis. They believe that ALC levels do not correlate directly with safety profiles as suggested by competitors [21][51][54]. 4. **Future Data Updates**: The next data update is expected at the **ASH** conference in December, which will provide additional follow-up data [34]. This summary encapsulates the key points discussed during the conference call, focusing on the company's product, its competitive advantages, and future plans in the biotechnology sector.

Company Performance - Arcellx, Inc. reported a quarterly loss of $1.13 per share, which was worse than the Zacks Consensus Estimate of a loss of $0.84, and compared to a loss of $0.14 per share a year ago, indicating a significant decline in performance [1] - The company posted revenues of $8.13 million for the quarter ended March 2025, missing the Zacks Consensus Estimate by 55.30%, and a decrease from year-ago revenues of $39.26 million [2] - Over the last four quarters, Arcellx has surpassed consensus EPS estimates only two times and has not beaten consensus revenue estimates during this period [2] Stock Movement and Outlook - Arcellx shares have declined approximately 31% since the beginning of the year, contrasting with the S&P 500's decline of -4.3% [3] - The company's future stock performance will largely depend on management's commentary during the earnings call and the revisions of earnings estimates [3][4] - The current consensus EPS estimate for the upcoming quarter is -$0.89 on revenues of $17.86 million, and for the current fiscal year, it is -$3.27 on revenues of $84.82 million [7] Industry Context - The Medical - Biomedical and Genetics industry, to which Arcellx belongs, is currently ranked in the top 33% of over 250 Zacks industries, suggesting a favorable industry outlook [8] - Empirical research indicates a strong correlation between near-term stock movements and trends in earnings estimate revisions, which could impact Arcellx's stock performance [5][6]

Financial Performance - Collaboration revenue decreased to $8.1 million for the three months ended March 31, 2025, down from $39.3 million in the same period of 2024, a decline of $31.1 million[100]. - Net losses for the three months ended March 31, 2025, were $62.3 million, compared to $7.2 million for the same period in 2024, an increase of $55.1 million[78]. - Total operating expenses rose to $77.0 million for the three months ended March 31, 2025, up from $55.1 million in 2024, an increase of $21.9 million[98]. - General and administrative expenses were $26.2 million for the three months ended March 31, 2025, compared to $22.7 million in the same period of 2024, an increase of $3.5 million[102]. - Net cash used in operating activities was $63.1 million for the three months ended March 31, 2025, compared to $31.9 million in the same period of 2024[110]. - The net decrease in cash, cash equivalents, and restricted cash was $24.8 million for the three months ended March 31, 2025, compared to a decrease of $241.7 million in the same period of 2024[109]. Research and Development - Research and development expenses increased to $50.8 million for the three months ended March 31, 2025, compared to $32.3 million in 2024, an increase of $18.5 million[98]. - Internal research and development costs rose by $12.3 million, primarily due to higher personnel-related costs of $9.8 million, including $7.3 million in non-cash share-based compensation[101]. - The company has initiated a Phase 1 trial for generalized myasthenia gravis (gMG) in 2024, expanding its clinical programs beyond oncology[77]. - The lead program, anito-cel, is currently being evaluated in pivotal Phase 2 and Phase 3 trials for relapsed or refractory multiple myeloma[74]. Future Outlook - The company expects to continue incurring significant operating losses and increasing expenses in the foreseeable future[79]. - The company anticipates substantial additional funding will be required to support ongoing development and operations[79]. - The company has not generated any product revenue to date and does not expect to do so until regulatory approval and commercialization of product candidates[106]. - The company expects to continue incurring significant losses for the foreseeable future as it develops and seeks regulatory approvals for its product candidates[106]. - The company anticipates that its current cash and cash equivalents will be adequate to fund operations into 2028 based on expected operating cash requirements[108]. - The current cash and cash equivalents are believed to be adequate to fund operations into 2028[80]. Cash and Securities - The company had cash and cash equivalents and marketable securities of $565.2 million as of March 31, 2025[105]. - Net cash provided by investing activities was $37.8 million for the three months ended March 31, 2025, primarily from maturities of marketable securities[112].

Financial Position - As of March 31, 2025, Arcellx had cash, cash equivalents, and marketable securities totaling $565.2 million, expected to fund operations into 2028[7]. - Total assets as of March 31, 2025, were $648.1 million, down from $711.3 million as of December 31, 2024[14]. - Total liabilities decreased to $231.2 million as of March 31, 2025, from $256.5 million as of December 31, 2024[14]. Revenue and Expenses - Collaboration revenue decreased to $8.1 million for Q1 2025 from $39.3 million in Q1 2024, a decline of $31.2 million[8]. - Research and development expenses increased to $50.8 million in Q1 2025, up from $32.3 million in Q1 2024, an increase of $18.5 million[9]. - General and administrative expenses rose to $26.2 million in Q1 2025, compared to $22.7 million in Q1 2024, an increase of $3.5 million[10]. - Net loss for Q1 2025 was $62.3 million, compared to a net loss of $7.2 million in Q1 2024[11]. Clinical Studies - The iMMagine-3 study has added minimal residual disease negativity as a dual primary endpoint alongside progression-free survival[2]. - The iMMagine-1 data will be presented at the European Hematology Association Congress on June 14, 2025[3]. Governance - Two new Board members, Andrew Galligan and Kristin Myers, were appointed to enhance commercial and operational expertise[4][6].

Group 1 - Baron is an asset management firm focused on delivering growth equity investment solutions [1] - Founded in 1982, Baron has become known for its long-term, fundamental, active approach to growth investing [1] - Research has remained at the core of Baron's business since its inception as an equity research firm [1]