IMA-203

The Company will now target five major cancer types with its four clinically active compounds across both TCR-T cell therapies and TCR-based Bispecifics Today, Company discloses first clinical data from the TCR Bispecific molecule, TCER® IMA402 targeting PRAME, in the Phase 1 dose escalation trial, demonstrating a favorable tolerability profile and signs of dose-dependent and PRAME expression-dependent clinical activity, including first objective responses in melanoma patients; early pharmacokinetics data indicate a median half-life of 7 days, potentially enabling bi-weekly dosing; dose escalation is ongoingSUPRAME, the randomized-controlled Phase 3 trial to evaluate ACTengine® IMA203 in 2L+ metastatic melanoma patients, planned to commence in December 2024; pre-specified interim data analysis planned for early 2026Recently, Company presented Phase 1b clinical data on ACTengine® IMA203 targeting PRAME that demonstrate deep and durable responses in heavily pretreated metastatic melanoma patients treated at RP2D; IMA203 continues to maintain a favorable tolerability profile in patients treated across all dose levelsNext-generation ACTengine® IMA203CD8 Phase 1a dose escalation data demonstrate enhanced pharmacology and potency per cell; TCR-T candidate to be evaluated for future development in solid cancers with medium-level PRAME copy numbers, such as ovarian and endometrial cancerClinical proof-of-concept data from the ongoing Phase 1 dose escalation trial with TCER® IMA401 targeting MAGEA4/8 demonstrate initial clinical anti-tumor activity in multiple tumor types and a manageable tolerability profile; dose escalation is ongoing$150 million public offering completed on October 15, 2024As of September 30, 2024, cash and cash equivalents as well as other financial assets amount to $549.2 million1 (€490.5 million), not including the cash inflow from the public offering on October 15, 2024; updated cash reach guidance into 2H 2027 Houston, Texas and Tuebingen, Germany, November 18, 2024 – Immatics N.V. (NASDAQ: IMTX, “Immatics” or the “Company”), a clinical-stage biopharmaceutical company active in the discovery and development of T cell-redirecting cancer immunotherapies, today provided a business update and reported financial results for the quarter ended September 30, 2024. The Company also reported the first clinical data update from the ongoing Phase 1 dose escalation trial evaluating its next-generation, half-life extended TCR Bispecific molecule, TCER® IMA402 targeting PRAME. “This year, Immatics has demonstrated the strength of its pipeline by announcing data on clinical activity for its four clinical-stage assets across two therapeutic modalities. These include ACTengine® IMA203 targeting PRAME positioned in 2L+ melanoma now moving forward into the Phase 3 trial SUPRAME targeting BLA filing in early 2027; ACTengine® IMA203CD8 targeting hard-to-treat solid cancers with an initial focus on ovarian and endometrial cancers; and TCER® IMA401 targeting MAGEA4/8 demonstrating clinical proof-of-concept during dose escalation and positioned in squamous NSCLC and head and neck cancer. Today, we are very pleased to announce first clinical data on TCER® IMA402 targeting PRAME, which show promising signals of anti-tumor activity during early dose escalation and is initially positioned in 1L+ melanoma,” said Harpreet Singh, Ph.D., CEO and Co-Founder of Immatics. “With our enhanced cash runway into the second half of 2027, Immatics is well positioned to advance all four candidates to highly relevant value inflection points with a specific focus on delivering meaningful clinical signals in multiple solid cancers in the coming year.” Third Quarter 2024 and Subsequent Company Progress TCR Bispecifics Programs TCER® IMA402 (PRAME) Today, Immatics is providing the first clinical data update from the ongoing Phase 1 dose escalation trial evaluating its next-generation, half-life extended TCR Bispecific molecule, TCER® IMA402 targeting PRAME. Patient Population: As of the data cut-off on November 6, 2024, 33 heavily pretreated patients with recurrent and/or refractory solid tumors have been treated with a dose range from 0.02 mg to 4 mg of IMA402 monotherapy. The treated patient population is composed of patients with a median of three and a maximum of five lines of prior systemic treatments. The safety population includes all 33 patients treated with IMA402, of which 21 patients were evaluable for efficacy analysis and are PRAME-positive or were not tested for PRAME. Of these 21 patients, eight patients received at least one dose of IMA402 at dose level 7 (DL7, 3 mg), and one patient received IMA402 at dose level 8 (DL8, 4 mg). Based on preclinical in-vivo data, relevant anti-tumor efficacy was expected starting at ~3 mg human equivalent dose, which aligns with the initial clinical anti-tumor activity reported today. Safety: IMA402 demonstrated a favorable tolerability profile in the 33 patients treated. The most common treatment-related adverse events (AEs) were mostly mild to moderate cytokine release syndrome (CRS) and transient lymphopenia. Step dosing has been implemented and dose escalation is ongoing. The maximum tolerated dose has not yet been determined. Pharmacokinetics: Early pharmacokinetic data indicate a median half-life of approximately seven days, potentially enabling bi-weekly dosing. Initial Anti-Tumor Activity: Initial signs of clinical activity have been observed and are associated with PRAME expression and IMA402 dose levels administered. In the PRAME-negative patient population across all doses and indications, only one patient out of seven (14%) showed tumor shrinkage of -2.9%.In comparison, in the PRAME-positive or non-tested patients across all indications treated with low dose levels (DLs 1-6), tumor shrinkage was observed in 25% (3/12) of patients, including one unconfirmed partial response in a cutaneous melanoma patient. Nine patients with tumors that tested PRAME-positive or were not tested for PRAME received a relevant dose (8 patients at DL7 and 1 patient at DL8). 78% (7/9) thereof experienced shrinkage of their target lesions, including several patients with significant ongoing tumor shrinkage: one cutaneous melanoma patient with an ongoing (at 3 months post first dose at data cut-off) confirmed partial response with -40.2% tumor shrinkage treated at DL7;two patients with ongoing (at 6+ weeks and 8+ months) stable diseases with significant tumor shrinkage (-27.5% in a patient with cutaneous melanoma at DL8 and at first scan; -25% in a patient with uveal melanoma deepening over time and treated at escalating doses starting at DL4 and currently at DL7);one ovarian cancer patient with ongoing (at 3 months) stable disease and tumor shrinkage of -13% started at DL6 and currently at DL7. Early Signs of Clinical Activity Associated with PRAME Expression and IMA402 Dose *Patients who received DL7 or higher, either from start or as part of intra-patient dose-escalation; #continuing treatment; PD: Progressive Disease; SD: Stable Disease; PR: Partial Response; cPR: confirmed Partial Response; BOR: Best Overall Response; BL: Baseline; NT: not tested or not evaluable for PRAME expression More information and details on the IMA402 clinical data are available on the Events & Presentations page of the Immatics corporate website: https://investors.immatics.com/events-presentations Based on these initial signs of dose-dependent and PRAME target expression-dependent clinical activity observed during dose escalation, the Company will continue to evaluate IMA402 at higher dose levels to determine the optimal therapeutic dose. The next data update on IMA402 is planned for 2025. TCER® IMA401 (MAGEA4/8) On September 16, 2024, Immatics announced the proof-of-concept clinical data for the first candidate of its next-generation, half-life extended TCR Bispecifics platform, TCER® IMA401 (MAGEA4/8), during an oral presentation at the European Society for Medical Oncology (ESMO) Congress 2024. As of data cut-off on July 23, 2024, 35 heavily pretreated patients with recurrent and/or refractory solid tumors were treated with IMA401 monotherapy across nine escalating dose levels. The treated patient population was composed of patients with 16 different solid tumor indications who were both HLA-A*02:01 and MAGEA4/8-positive, had received a median of four and up to eight lines of prior systemic treatments and the majority had an ECOG performance status of ≥ 1. Proof-of-concept clinical data from the Phase 1a first-in-human dose escalation basket trial showed initial anti-tumor activity in multiple tumor types, durable objective responses, including confirmed responses ongoing at 13+ months, a manageable tolerability profile and a half-life of 14+ days. Treatment with IMA401 monotherapy in patients with relevant IMA401 doses and MAGEA4/8high levels (N=17) demonstrated: Objective response rate of 29% with confirmed responses observed in 25% of patients Disease control rate of 53% and tumor shrinkage of 53% As the clinical trial progresses, the Company aims to further leverage the potential of IMA401 by focusing on the enrollment of indications with high MAGEA4/8 target expression, such as lung and head and neck cancer patients, seeking to optimize the treatment schedule and also exploring the incremental clinical benefit available to patients through combining IMA401 with a checkpoint inhibitor. The next data update on IMA401 is expected in 2025. ACTengine® Cell Therapy Programs ACTengine® IMA203 On November 8, 2024, Immatics announced an expanded clinical dataset that included all infused patients in the Phase 1b dose expansion part of the trial (N=41), consisting of the 28 melanoma patients reported on October 10, 2024, and 13 non-melanoma patients, of which 10 non-melanoma patients were reported on November 8, 2023. As of the data cut-off on August 23, 2024, treatment with IMA203 monotherapy in the melanoma patient population has demonstrated: Confirmed objective response rate of 54% and an objective response rate of 62% Disease control rate of 92% and tumor shrinkage in 88% of patients12.1 months median duration of response, 6 months median progression-free survival and >1-year median progression-free survival in patients with deep responsesMedian overall survival has not yet been reached IMA203 monotherapy has maintained a favorable tolerability profile with no treatment-related Grade 5 events in the entire safety population (N=70 Phase 1a and Phase 1b patients across all dose levels and all tumor types). Based on the Phase 1b data and discussions with the U.S. Food and Drug Administration, Immatics is on track to commence SUPRAME, the registration-enabling Phase 3 randomized-controlled clinical trial in melanoma for IMA203, in December 2024. SUPRAME will evaluate IMA203 targeting PRAME in 360 HLA-A*02:01-positive patients with second-line or later (2L+) unresectable or metastatic melanoma who have received prior treatment with a checkpoint inhibitor. Patients will be randomized 1:1 for IMA203 or investigator’s choice of selected approved treatments in the 2L+ setting, including nivolumab/relatlimab, nivolumab, ipilimumab, pembrolizumab, lifileucel (U.S. only) or chemotherapy. The primary endpoint for full approval will be median PFS and secondary endpoints will include objective response rate, safety, duration of response, no overall survival detriment and patient-reported outcomes. Patient enrollment for SUPRAME is forecast to be completed in 2026, and a pre-specified interim analysis is planned for early 2026. Immatics aims to submit a Biologics License Application (BLA) in early 2027 for full approval. ACTengine® IMA203CD8 (GEN2) monotherapy On November 8, 2024, Immatics announced updated Phase 1 dose escalation clinical data on its next-generation ACTengine® IMA203CD8 TCR-T cell therapy in 44 heavily pretreated HLA-A*02:01 and PRAME-positive patients with solid tumors, thereof 41 patients being evaluable for efficacy. Of note, these patients had been treated at substantially lower doses compared to IMA203 (GEN1), i.e. in a range of 0.2-0.48x109 TCR-T cells/m2 BSA (dose level 3) to 0.801-1.2x109 TCR-T cells/m2 BSA (dose level 4c) T cells infused. As of the data cut-off on September 30, 2024, treatment with IMA203CD8 monotherapy demonstrated: Confirmed objective responses observed in 41% of patientsMedian duration of response of 9.2 months at a median follow-up of 13.1 monthsTumor shrinkage of 84% and disease control rate at week 6 of 85%10 out of 17 responses were ongoing, of which three confirmed responses were ongoing at 14+, 15+ and 24+ months Deep responses with ≥50% tumor size reduction were observed in 11 out of 17 responders. This group included two patients with complete response of target lesions, of which one patient showed a complete metabolic response according to PET-CT scan IMA203CD8 monotherapy has maintained a manageable tolerability profile in the 44 patients treated. Based on the enhanced pharmacology of IMA203CD8 demonstrated in this trial, the evaluation of higher doses of IMA203CD8 in the ongoing dose escalation trial opens the possibility of addressing hard-to-treat solid tumor indications with a medium-level of PRAME copy numbers, such as ovarian cancer and endometrial cancer. Corporate Development In September 2024, Immatics regained full clinical development and commercialization rights to IMA401 due to ongoing portfolio prioritization efforts within Bristol Myers Squibb. The Phase 1 dose escalation trial with IMA401 is ongoing and will continue to be conducted by Immatics. Third Quarter 2024 Financial Results Cash Position: Cash and cash equivalents as well as other financial assets total $549.2 million1 (€490.5 million) as of September 30, 2024, compared to $476.8 million1 (€425.9 million) as of December 31, 2023. The increase is mainly due to the public offering in January 2024, partly offset by ongoing research and development activities. Following the $150 million public offering in October 2024, the Company now projects a cash runway into the second half of 2027. Revenue: Total revenue, consisting of revenue from collaboration agreements, was $56.7 million1 (€50.6 million) for the three months ended September 30, 2024, compared to $6.6 million1 (€5.9 million) for the three months ended September 30, 2023. The increase is mainly the result of a one-time revenue associated with the termination of the IMA401 collaboration by Bristol Myers Squibb during the three months ended September 30, 2024. Research and Development Expenses: R&D expenses were $43.6 million1 (€38.9 million) for the three months ended September 30, 2024, compared to $34.1 million1 (€30.5 million) for the three months ended September 30, 2023. The increase mainly resulted from costs associated with the advancement of the clinical pipeline candidates.General and Administrative Expenses: G&A expenses were $12.5 million1 (€11.2 million) for the three months ended September 30, 2024, compared to $10.0 million1 (€8.9 million) for the three months ended September 30, 2023. Net Profit and Loss: Net loss was $9.6 million1 (€8.6 million) for the three months ended September 30, 2024, compared to a net loss of $29.7 million1 (€26.5 million) for the three months ended September 30, 2023. The decrease in net loss results from the increase in recognized revenue in the period. Full financial statements can be found in the 6-K filed with the Securities and Exchange Commission (SEC) on November 18, 2024, and published on the SEC website under www.sec.gov. Upcoming Investor Conferences Jefferies London Healthcare Conference, London, United Kingdom – November 19 – 21, 2024 To see the full list of events and presentations, visit www.investors.immatics.com/events-presentations. About IMA402TCER® IMA402 is a drug candidate owned by Immatics. IMA402 is Immatics’ second TCER® molecule from the bispecifics pipeline and is directed against an HLA-A*02-presented peptide derived from preferentially expressed antigen in melanoma (PRAME), a protein frequently expressed in a large variety of solid cancers, thereby supporting the program’s potential to address a broad cancer patient population. Immatics’ PRAME peptide is present at a high copy number per tumor cell and is homogenously and specifically expressed in tumor tissue. The peptide has been identified and characterized by Immatics’ proprietary mass spectrometry-based target discovery platform, XPRESIDENT®. IMA402 is part of Immatics’ strategy to leverage the full clinical potential of targeting PRAME, one of the most promising targets for TCR-based therapies. - END - About ImmaticsImmatics combines the discovery of true targets for cancer immunotherapies with the development of the right T cell receptors with the goal of enabling a robust and specific T cell response against these targets. This deep know-how is the foundation for our pipeline of Adoptive Cell Therapies and TCR Bispecifics as well as our partnerships with global leaders in the pharmaceutical industry. We are committed to delivering the power of T cells and to unlocking new avenues for patients in their fight against cancer. Immatics intends to use its website www.immatics.com as a means of disclosing material non-public information. For regular updates you can also follow us on X, Instagram and LinkedIn. Forward-Looking StatementsCertain statements in this press release may be considered forward-looking statements. Forward-looking statements generally relate to future events or the Company’s future financial or operating performance. For example, statements concerning timing of data read-outs for product candidates, the timing, outcome and design of clinical trials, the nature of clinical trials (including whether such clinical trials will be registration-enabling), the timing of IND or CTA filing for pre-clinical stage product candidates, estimated market opportunities of product candidates, the Company’s focus on partnerships to advance its strategy, and other metrics are forward-looking statements. In some cases, you can identify forward-looking statements by terminology such as “may”, “should”, “expect”, “plan”, “target”, “intend”, “will”, “estimate”, “anticipate”, “believe”, “predict”, “potential” or “continue”, or the negatives of these terms or variations of them or similar terminology. Such forward-looking statements are subject to risks, uncertainties, and other factors which could cause actual results to differ materially from those expressed or implied by such forward-looking statements. These forward-looking statements are based upon estimates and assumptions that, while considered reasonable by Immatics and its management, are inherently uncertain. New risks and uncertainties may emerge from time to time, and it is not possible to predict all risks and uncertainties. Factors that may cause actual results to differ materially from current expectations include, but are not limited to, various factors beyond management's control including general economic conditions and other risks, uncertainties and factors set forth in the Company’s Annual Report on Form 20-F and other filings with the Securities and Exchange Commission (SEC). Nothing in this press release should be regarded as a representation by any person that the forward-looking statements set forth herein will be achieved or that any of the contemplated results of such forward-looking statements will be achieved. You should not place undue reliance on forward-looking statements, which speak only as of the date they are made. The Company undertakes no duty to update these forward-looking statements. All the scientific and clinical data presented within this press release are – by definition prior to completion of the clinical trial and a clinical study report – preliminary in nature and subject to further quality checks including customary source data verification. For more information, please contact: Media Trophic Communications Phone: +49 171 3512733 immatics@trophic.eu Immatics N.V. Jordan Silverstein Head of Strategy Phone: +1 346 319-3325 InvestorRelations@immatics.com Immatics N.V. and subsidiariesCondensed Consolidated Statement of Loss of Immatics N.V. Three months ended September 30, Nine months ended September 30, 2024 2023 2024 2023 (Euros in thousands, exceptper share data) (Euros in thousands, exceptper share data) Revenue from collaboration agreements 50,559 5,926 99,583 38,076 Research and development expenses (38,906) (30,498) (106,230) (85,396) General and administrative expenses (11,156) (8,881) (32,925) (27,825) Other income 17 186 54 1,134 Operating result 514 (33,267) (39,518) (74,011) Change in fair value of liabilities for warrants 3,833 (1,395) 4,228 (7,103) Other financial income 5,889 9,748 18,707 14,414 Other financial expenses (12,589) (1,575) (5,342) (4,146) Financial result (2,867) 6,778 17,593 3,165 Loss before taxes (2,353) (26,489) (21,925) (70,846) Taxes on income (6,217) — (7,720) — Net loss (8,570) (26,489) (29,645) (70,846) Net loss per share: Basic (0.08) (0.32) (0.29) (0.90) Diluted (0.11) (0.32) (0.31) (0.90) Immatics N.V. and subsidiariesCondensed Consolidated Statement of Comprehensive Loss of Immatics N.V. Three months ended September 30, Nine months ended September 30, 2024 2023 2024 2023 (Euros in thousands) (Euros in thousands) Net loss (8,570) (26,489) (29,645) (70,846) Other comprehensive income Items that may be reclassified subsequently to profit or loss Currency translation differences from foreign operations (1,377) 429 (579) 769 Total comprehensive loss for the year (9,947) (26,060) (30,224) (70,077) Immatics N.V. and subsidiariesCondensed Consolidated Statement of Financial Position of Immatics N.V. As of September 30,2024 December 31,2023 (Euros in thousands) Assets Current assets Cash and cash equivalents 189,199 218,472 Other financial assets 301,321 207,423 Accounts receivables 2,951 4,093 Other current assets 19,306 19,382 Total current assets 512,777 449,370 Non-current assets Property, plant and equipment 48,424 43,747 Intangible assets 1,506 1,523 Right-of-use assets 13,327 13,308 Other non-current assets 1,199 2,017 Total non-current assets 64,456 60,595 Total assets 577,233 509,965 Liabilities and shareholders’ equity Current liabilities Provisions 5,144 — Accounts payables 22,095 25,206 Deferred revenue 68,928 100,401 Liabilities for warrants 14,765 18,993 Lease liabilities 2,825 2,604 Other current liabilities 15,155 9,348 Total current liabilities 128,912 156,552 Non-current liabilities Deferred revenue 52,597 115,527 Lease liabilities 13,198 12,798 Other non-current liabilities — 4 Total non-current liabilities 65,795 128,329 Shareholders’ equity Share capital 1,031 847 Share premium 1,010,648 823,166 Accumulated deficit (626,938) (597,293) Other reserves (2,215) (1,636) Total shareholders’ equity 382,526 225,084 Total liabilities and shareholders’ equity 577,233 509,965 Immatics N.V. and subsidiariesCondensed Consolidated Statement of Cash Flows of Immatics N.V. Nine months ended September 30, 2024 2023 (Euros in thousands) Cash flows from operating activities Net loss (29,645) (70,846) Taxes on income 7,720 — Loss before tax (21,925) (70,846) Adjustments for: Interest income (18,185) (8,993) Depreciation and amortization 9,149 5,432 Interest expenses 654 620 Equity-settled share-based payment 13,112 16,299 Loss from disposal of fixed assets 1 Net foreign exchange differences and expected credit losses 4,018 (760) Change in fair value of liabilities for warrants (4,228) 7,103 Changes in: Decrease in accounts receivables 1,142 596 Decrease/(increase) in other assets (2,623) 658 (Decrease) in deferred revenue, accounts payables and other liabilities (91,113) (15,641) Interest received 11,098 4,904 Interest paid (654) (221) Income tax paid — — Net cash used in operating activities (99,554) (60,849) Cash flows from investing activities Payments for property, plant and equipment (14,598) (21,506) Payments for intangible assets (148) (158) Payments for investments classified in other financial assets (356,596) (299,018) Proceeds from maturity of investments classified in other financial assets 266,361 229,557 Proceeds from disposal of property, plant and equipment 1 — — — Net cash used in investing activities (104,980) (91,125) Cash flows from financing activities Proceeds from issuance of shares to equity holders 174,554 90,404 Transaction costs deducted from equity (2,039) Repayments related to lease liabilities (1,228) (2,877) Net cash provided by financing activities 173,326 85,488 Net decrease in cash and cash equivalents (31,208) (66,486) Cash and cash equivalents at beginning of the year 218,472 148,519 Effects of exchange rate changes, expected credit losses and accrued intereston cash and cash equivalents 1,935 1,413 Cash and cash equivalents at end of the year 189,199 83,446 Immatics N.V. and subsidiariesCondensed Consolidated Statement of Changes in Shareholders’ Equity of Immatics N.V. (Euros in thousands) Sharecapital Sharepremium Accumulateddeficit Otherreserves Totalshare-holders’equity Balance as of January 1, 2023 767 714,177 (500,299) (1,481) 213,164 Other comprehensive income — — — 769 769 Net loss — — (70,846) — (70,846) Comprehensive loss for the year — — (70,846) 769 (70,077) Equity-settled share-based compensation — 16,299 — — 16,299 Share options exercised — 140 — — 140 Issue of share capital – net of transaction costs 80 88,145 — — 88,225 Balance as of September 30, 2023 847 818,761 (571,145) (712) 247,751 Balance as of January 1, 2024 847 823,166 (597,293) (1,636) 225,084 Other comprehensive income — — — (579) (579) Net loss — — (29,645) — (29,645) Comprehensive loss for the year — — (29,645) (579) (30,224) Equity-settled share-based compensation — 13,112 — — 13,112 Share options exercised 1 1,113 — — 1,114 Issue of share capital – net of transaction costs 183 173,257 — — 173,440 Balance as of September 30, 2024 1,031 1,010,648 (626,938) (2,215) 382,526 1 All amounts translated using the exchange rate published by the European Central Bank in effect as of September 30, 2024 (1 EUR = 1.1196 USD). 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Two oral presentations and multiple posters on clinical and preclinical-stage candidates to be presented at SITC, demonstrating the strength of Immatics’ TCR-T PRAME franchise to target solid cancers HOUSTON, TX and TUEBINGEN, Germany I November 8, 2024 I Immatics N.V. (NASDAQ: IMTX, “Immatics” or the “Company”), a clinical-stage biopharmaceutical company active in the discovery and development of T cell-redirecting cancer immunotherapies, today announced an expanded clinical dataset from the ongoing Phase 1b dose expansion clinical trial for ACTengine® IMA203 in addition to updated Phase 1 dose escalation clinical data on its next-generation ACTengine® IMA203CD8 TCR-T cell therapy. For the first time, the Company also reported preclinical data on other next-generation T cell candidates and combination strategies as part of its strategy to further exploit opportunities in additional solid tumor types within its PRAME franchise. All dates and times of Immatics’ upcoming oral and poster presentations at the 39 th Annual Meeting of the Society for Immunotherapy of Cancer (SITC) are available here . The data slides are accessible in the ‘ Events & Presentations ’ section of the Investor & Media section of the Company’s website. “Immatics remains fully focused on the clinical development of our most advanced lead product candidate, IMA203, in second-line or later metastatic melanoma patients. We look forward to the initiation of SUPRAME, the registration-enabling Phase 3 trial, in December,” said Dr. Cedrik Britten, Chief Medical Officer at Immatics. “Today, we also provide an update on our first, next-generation cell therapy, IMA203CD8, which is designed to achieve enhanced anti-tumor activity. The data announced confirm IMA203CD8’s enhanced pharmacology and potency per cell in patients. These attributes highlight the potential of this therapy in hard-to-treat solid tumors with medium-level PRAME copy numbers, including ovarian, endometrial and triple-negative breast cancer. The next step will be to further increase the cell dose to assess the full clinical potential of IMA203CD8 beyond melanoma. In addition, we strive to continuously improve the potential therapeutic benefit for patients with a range of PRAME-positive cancers through the expansion of our PRAME franchise.” ACTengine® IMA203 Monotherapy Phase 1b Trial – Clinical Data and Development Path Summary On October 10, 2024 , Immatics provided a data update on IMA203 monotherapy in 28 1 heavily pretreated metastatic melanoma patients from the ongoing Phase 1b dose expansion part of the clinical trial in which patients were treated at the recommended Phase 2 dose (RP2D, 1 to 10 billion total TCR-T cells). The data announced today include all infused patients in the Phase 1b dose expansion part of the trial (N=41 2 ), consisting of the 28 melanoma patients reported on October 10, 2024, and 13 non-melanoma patients, of which 10 non-melanoma patients were reported on November 8, 2023. IMA203 monotherapy has maintained a favorable tolerability profile with no treatment-related Grade 5 events in the entire safety population (N=70 3 Phase 1a and Phase 1b patients across all dose levels and all tumor types). Best Overall Response for IMA203 in Dose Expansion in All Indications (N=41 # ) Data cut-off Aug 23, 2024; # First tumor assessment post infusion pending for 2/28 melanoma patients at data-cut; *Maximum change of target lesions and RECIST1.1 response at different timepoints. 1 Patient A-DL5-23 is off study at data cut-off; 2 Patient received one dose nivolumab erroneously. Development Path for IMA203 Based on the Phase 1b data, the Company is on track to commence SUPRAME, the registration-enabling Phase 3 randomized-controlled clinical trial in melanoma for IMA203, in December 2024. SUPRAME will evaluate IMA203 targeting PRAME in 360 HLA-A*02:01-positive patients with second-line or later (2L+) unresectable or metastatic melanoma who have received prior treatment with a checkpoint inhibitor. Patients will be randomized 1:1 for IMA203 or investigator’s choice of selected approved treatments in the 2L+ setting, including nivolumab/relatlimab, nivolumab, ipilimumab, pembrolizumab, lifileucel (US only) or chemotherapy. The primary endpoint for full approval will be median PFS and secondary endpoints will include objective response rate, safety, duration of response, no overall survival detriment and patient-reported outcomes. Patient enrollment for SUPRAME is forecast to be completed in 2026, and a pre-specified interim analysis is planned for early 2026. Immatics aims to submit a Biologics License Application (BLA) in early 2027 for full approval. ACTengine® IMA203CD8 (GEN2) Monotherapy Phase 1 Dose Escalation Trial – Patient Population & Clinical Data Summary Patient population: Heavily pretreated patients with solid tumors As of data cut-off on September 30, 2024, 44 4 heavily pretreated HLA-A*02:01 and PRAME-positive patients with solid tumors were infused with IMA203CD8 monotherapy across four escalating dose levels, of which 41 5 patients were evaluable for efficacy. The median total infused dose was 1.48×10 9 TCR-T cells, and the patient population is composed of patients with a median of three lines of prior systemic treatments. Safety: Treatment with IMA203CD8 demonstrates a manageable tolerability profile across dose levels IMA203CD8 monotherapy has maintained a manageable tolerability profile in the 44 patients treated. The most frequent adverse events at or above Grade 3 were expected cytopenia associated with lymphodepletion. Some patients also experienced mild to moderate CRS (Grade 1: 36% Grade 2: 48% Grade 3: 11% Grade 4: 2%). As previously reported, two patients experienced dose-limiting toxicities at dose level 4b, which prompted a dosing adjustment to dose level 4a. After further assessing the tolerability profile of IMA203CD8 in additional patients treated at dose level 4a, the eligibility criteria and the IL-2 dose regimen were modified, and dose escalation beyond dose level 4a was reinitiated. One Grade 5 adverse event classified as possibly related to treatment with IMA203CD8 was also observed as reported previously in March 2024. The maximum tolerated dose has not yet been determined. Anti-tumor activity and durability: Deep and durable objective responses observed Translational data: Opportunity of IMA203CD8 in medium-level PRAME expressing indications Translational data indicate that PRAME expression level is associated with clinical activity in IMA203 and IMA203CD8 treated patients. Both IMA203 and IMA203CD8 achieved deep responses despite IMA203CD8 patients receiving lower product doses. Based on the enhanced pharmacology of IMA203CD8, the evaluation of higher doses of IMA203CD8 in the ongoing dose escalation trial opens the possibility of addressing hard-to-treat solid tumor indications with a medium-level of PRAME copy numbers, such as ovarian cancer, endometrial cancers and triple-negative breast cancer. Preclinical Data on New Approaches for TCR-T Based Cell Therapies As part of Immatics’ long-term strategy to expand its PRAME franchise, the Company has conducted preclinical studies for the potential future clinical development of next-generation TCR-T-based cell therapies targeting PRAME to further enhance the efficacy and durability of IMA203. These efforts include the evaluation of TCR-T cells armored with membrane-bound IL-15 (mbIL15) targeting tumor types with low PRAME copy numbers, such as squamous non-small-cell lung cancer and squamous head and neck cancers. In addition, the Company is developing an allogeneic cell therapy approach to further increase commercial attractiveness and to reach patients quickly with its next-generation off-the-shelf cell therapy, ACTallo®. The preclinical data will be presented during poster sessions at SITC. About ACTengine® IMA203, IMA203CD8 and Target PRAME ACTengine ® IMA203 is Immatics’ most advanced TCR-based autologous cell therapy that is directed against an HLA-A*02-presented (human leukocyte antigen) peptide derived from preferentially expressed antigen in melanoma (PRAME), a protein frequently expressed in a large variety of solid cancers. PRAME is homogeneously and specifically expressed in tumor tissue and Immatics’ PRAME peptide is present at a high copy number per tumor cell. The peptide has been identified and characterized by Immatics’ proprietary mass spectrometry-based target discovery platform, XPRESIDENT ® . Through its proprietary TCR discovery and engineering platform XCEPTOR ® , Immatics has generated a highly specific T cell receptor (TCR) against this target for ACTengine ® IMA203. ACTengine ® IMA203 TCR-T is currently being evaluated as a monotherapy in a Phase 1 clinical trial in patients with solid tumors expressing PRAME, such as cutaneous melanoma. An IMA203 registration-enabling randomized controlled Phase 3 trial, “SUPRAME,” is planned to commence in December 2024. ACTengine® IMA203 TCR-T is also currently being evaluated in Phase 1 IMA203CD8 (GEN2) monotherapy, where IMA203 engineered T cells are co-transduced with a CD8αβ co-receptor. – END – About Immatics Immatics combines the discovery of true targets for cancer immunotherapies with the development of the right T cell receptors with the goal of enabling a robust and specific T cell response against these targets. This deep know-how is the foundation for our pipeline of Adoptive Cell Therapies and TCR Bispecifics as well as our partnerships with global leaders in the pharmaceutical industry. We are committed to delivering the power of T cells and to unlocking new avenues for patients in their fight against cancer. Immatics intends to use its website www.immatics.com as a means of disclosing material non-public information. For regular updates you can also follow us on X , Instagram and LinkedIn . 1 Includes one patient who started lymphodepletion but did not receive IMA203 TCR-T cells. 2 All infused patients, first tumor assessment post infusion pending for 2/28 melanoma patients at data-cut. 3 All patients who started lymphodepletion as of the data cut-off on August 23, 2024. 4 All patients who started lymphodepletion. 5 All infused patients with at least one tumor assessment postbaseline. 6 Metabolic CR on investigator-initiated PET month 14 post infusion. 7 Three patients excluded from tumor shrinkage analysis and figures due to lack of post-treatment assessment. 8 One patient had an early tumor assessment, outside the first assessment visit window and is not included in DCR calculation. SOURCE: Immatics