PRAME-directed Cell Therapy Using Immatics’ TCR Induces Deep and Durable Remission in Pediatric Patient with Advanced Metastatic Nephroblastoma
Rhea-AI Summary
Immatics (NASDAQ: IMTX) reported a late-breaking AACR 2026 poster of an individual pediatric case showing deep, durable remission after treatment with a PRAME-directed TCR T-cell therapy.
A 17-year-old with metastatic PRAME-positive nephroblastoma (16 cm abdominal lesion; lung, liver, brain mets) achieved radiologic and molecular remission with response ongoing at 6 months; cytokine release syndrome was manageable and resolved.
Positive
- Deep remission observed at 3 months and ongoing at 6 months
- Marked regression of liver, lung and brain metastases
- Molecular remission evidenced by absence of tumor-derived DNA
- Large tumor burden reduced from 16 cm abdominal lesion
- Manageable CRS resolved with multi-modal anti-cytokine therapy and corticosteroids
Negative
- Single-patient individual treatment limits generalizability to broader pediatric populations
- Safety signal: patient experienced cytokine release syndrome requiring multi-modal therapy
News Market Reaction – IMTX
On the day this news was published, IMTX gained 2.76%, reflecting a moderate positive market reaction.
Data tracked by StockTitan Argus on the day of publication.
Key Figures
Market Reality Check
Peers on Argus
IMTX was down 1.18% pre‑announcement while close biotech peers were mixed: AVBP +1.21%, MNMD +1.08%, GYRE -1.25%, DAWN -0.09%, TNGX 0.00%, indicating stock‑specific factors rather than a unified sector move.
Historical Context
| Date | Event | Sentiment | Move | Catalyst |
|---|---|---|---|---|
| Mar 05 | Full-year results | Positive | -0.3% | Cash runway to 2028 and PRAME program timelines in FY 2025 update. |
| Dec 11 | Clinical data update | Positive | -0.2% | IMA203CD8 Phase 1a data with 36% cORR and durable responses. |
| Dec 05 | Equity offering | Negative | -14.2% | $125M underwritten share offering at $10 per share. |
| Nov 17 | Quarterly results | Positive | -7.2% | Q3 2025 update with PRAME trials advancing and detailed bispecific data. |
| Nov 12 | Bispecific PoC data | Positive | +16.1% | Phase 1a PoC for IMA402 and IMA401 with 30% cORR at RP2D range. |
Good clinical and business updates have often met muted or negative 1‑day reactions, while clearly dilutive offerings and strong PoC data aligned with larger price moves.
Over the last six months, Immatics has repeatedly highlighted progress in its PRAME franchise. On Nov 12, 2025, next‑generation TCER® bispecifics IMA402 and IMA401 showed clinical proof‑of‑concept with a 30% cORR for IMA402 and meaningful activity for IMA401, driving a 16.1% gain. Subsequent Q3 and full‑year 2025 updates emphasized cash resources and Phase 3/SUPRAME and bispecific timelines but saw modest declines. A $125M underwritten offering on Dec 5, 2025 led to a -14.24% move. Today’s pediatric PRAME TCR case builds on this clinical narrative, extending it into pediatric solid tumors.
Market Pulse Summary
This announcement highlights a 17-year-old with PRAME-positive metastatic nephroblastoma achieving deep, ongoing remission at 6 months after a PRAME-directed TCR T-cell therapy based on Immatics’ IMA203CD8 vector. The case complements earlier adult PRAME data by extending the approach into pediatric solid tumors. Investors may track how Immatics translates this into formal trials, including the potential Phase 1/2 basket study, and will likely watch for larger cohorts, durability data beyond 6 months, and safety signals such as cytokine release syndrome management.
Key Terms
tcr t-cell therapy medical
nephroblastoma medical
lentiviral vector medical
pet scan medical
mri imaging medical
cytokine release syndrome medical
hla-a*02:01-positive medical
AI-generated analysis. Not financial advice.
- Individual experimental treatment attempt at Hopp Children’s Cancer Center Heidelberg (KiTZ) and Heidelberg University Hospital (UKHD) using a TCR T-cell therapy engineered with a PRAME-directed TCR provided by Immatics
- 17-year-old adolescent with bulky, rapidly progressing nephroblastoma and no remaining treatment options achieved deep remission, including marked regression of liver, lung and brain metastases; response ongoing at 6 months of follow-up
- PRAME is a multi-pediatric cancer target, and findings highlight the therapeutic potential of PRAME TCR T-cell therapy in pediatric patients with solid tumors
- Data will be presented in a late-breaking poster at the AACR Annual Meeting 2026 by Dr. med. Christian M. Seitz, Group Leader at KiTZ
Houston, Texas and Tuebingen, Germany, April 17, 2026 – Immatics N.V. (NASDAQ: IMTX, “Immatics” or the “Company”), the global leader in precision targeting of PRAME with multiple clinical-stage programs spanning cell therapies and bispecifics, today announced that an abstract highlighting a pediatric patient treated with a PRAME-directed cell therapy using Immatics’ PRAME T-cell receptor (TCR) has been accepted for a late-breaking poster presentation at the American Association for Cancer Research (AACR) Annual Meeting 2026 in San Diego, California, USA. The patient case will be presented on April 21, 2026, at 2:00 pm PDT (Late-Breaking Research: Clinical Research 3; Poster Section 52; Poster Board Number 7; Abstract Number LB326) by the treating physician, Dr. med. Christian M. Seitz, Group Leader at the Hopp Children’s Cancer Center Heidelberg (KiTZ).
The abstract highlights the case of a 17-year-old adolescent with PRAME-positive advanced nephroblastoma, a malignant kidney cancer that predominantly occurs in children. The patient had rapidly progressing disease with metastases to the lung, liver and brain with an abdominal lesion measuring 16 cm in longest diameter. After exhausting all available treatment options and being ineligible for any ongoing clinical trial, the treating physician requested Immatics’ PRAME-directed TCR (encoded by the IMA203CD8 lentiviral vector) for an individual experimental treatment attempt (named-patient use; “Individueller Heilversuch” in Germany) at KiTZ, where a TCR T-cell therapy was manufactured. Following treatment, the patient experienced a deep anti-tumor response, with remission observed three months post-infusion and ongoing at six months of follow-up. PET scan and MRI imaging demonstrated marked tumor regression across all lesion sites. Additionally, liquid biopsy monitoring showed no more tumor-derived DNA, indicating molecular remission. Safety events reported in the abstract by the treating physician included cytokine release syndrome, which was manageable and resolved under multi-modal anti-cytokine therapy and corticosteroids. At six months of follow-up, the patient is in excellent physical condition.
“We are very grateful to Immatics for providing the PRAME-directed TCR that enabled us to reprogram the pediatric patient’s cells. We hope that possible further clinical evaluation may demonstrate the potential of PRAME-targeted cellular immunotherapies in helping other children and adolescents with cancer, as seen in this patient,” said Christian M. Seitz, M.D., treating physician and Group Leader of the Translational Immunotherapy group at KiTZ, German Cancer Research Center (DKFZ) and Heidelberg University Hospital (UKHD).
Cedrik Britten, M.D., Ph.D., Chief Medical Officer at Immatics, added, “Seeing such a profound response in a pediatric patient who had no treatment options left is both remarkable and deeply encouraging for everyone dedicated to making a meaningful impact on the lives of patients with cancer. It reinforces our belief in PRAME as a powerful target and highlights the potential of cell therapy for pediatric cancers, where tumors often show high PRAME expression. These results support continued evaluation of PRAME-directed cell therapies in pediatric cancers while exploring new therapeutic options for children facing such devastating diseases.”
PRAME is a tumor target present on the cell surface of more than 50 cancers and can be targeted by TCR T-cell therapies. Based on the high PRAME expression across multiple different pediatric tumors in combination with the potential benefit of particularly strong immune responses in young patients, PRAME TCR T-cell therapies may offer a promising new treatment option for these patients. Immatics is planning to evaluate the potential of its PRAME TCR T-cell therapy candidates in pediatric patients with cancer and is assessing multiple options for clinical development including a potential first-in-pediatrics Phase 1/2 basket study in pediatric patients with HLA-A*02:01-positive, PRAME-expressing relapsed or refractory solid tumors at KiTZ in Heidelberg.
About Immatics’ PRAME-Directed Cell Therapies
Immatics is developing PRAME-directed TCR T-cell therapies engineered to recognize an intracellular PRAME-derived peptide presented by HLA-A*02:01 on the surface of tumor cells and to initiate a potent and specific anti-tumor response.
Immatics’ PRAME-directed cell therapies are being evaluated in clinical trials across multiple PRAME-positive solid tumors in adult patients. Its lead PRAME cell therapy candidate, anzu-cel (anzutresgene autoleucel, IMA203) is currently being evaluated in a registration-enabling Phase 3 trial “SUPRAME” in previously treated advanced cutaneous melanoma and a Phase 2 trial in metastatic uveal melanoma. In addition, Immatics is evaluating its second-generation PRAME cell therapy, IMA203CD8, in a Phase 1a dose escalation trial in patients with PRAME-positive solid tumors, with a focus on gynecologic cancers.
About PRAME
PRAME is a target expressed in more than 50 cancers. Immatics is the global leader in precision targeting of PRAME and has the broadest PRAME franchise with the most PRAME indications and modalities. The Immatics PRAME franchise currently includes three product candidates, two therapeutic modalities and two combination therapies that target PRAME: anzu-cel (anzutresgene autoleucel, IMA203) PRAME cell therapy, IMA203CD8 PRAME cell therapy (GEN2), IMA402 PRAME bispecific as monotherapy and in combination with an immune checkpoint inhibitor as well as anzu-cel in combination with Moderna’s PRAME mRNA designed to enhance cell therapy.
About Immatics
Immatics is committed to making a meaningful impact on the lives of patients with cancer. We are the global leader in precision targeting of PRAME, a target expressed in more than 50 cancers. Our cutting-edge science and robust clinical pipeline form the broadest PRAME franchise with the most PRAME indications and modalities, spanning TCR T-cell therapies and TCR bispecifics.
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 LinkedIn and Instagram.
Forward-Looking Statements
Certain 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, observations from the Company’s clinical trials, 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, CTA or BLA filings, 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: +49 151 74416179
immatics@trophic.eu
Immatics N.V.
Jordan Silverstein
Head of Strategy
Phone: +1 346 319-3325
InvestorRelations@immatics.com
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