A Clinical Study Investigating the Therapeutic Effects and Safety of an Investigational Cell Therapy Given With and Without an Additional Investigational Product in Males With Testicular Cancer or a Form of Cancer That Developed From Sperm (AVENTURINE)

Open-label Phase II Trial to Evaluate Anti-tumor Activity and Safety of CLDN6 CAR-T ± CLDN6 RNA-LPX in Male Participants With Relapsed or Refractory Claudin 6-positive Testicular or Extragonadal Germ Cell Tumors

This study is designed to evaluate the safety, efficacy, cellular kinetics, and immunogenicity of Claudin 6 (CLDN6) Chimeric antigen receptor T cell (CAR-T) ± CLDN6 ribonucleic acid-lipoplex (RNA-LPX) in participants born male with relapsed or refractory CLDN6-positive testicular or extragonadal germ cell tumors (GCTs) after prior salvage therapy.

Study Overview

• Status: Withdrawn
• Conditions: Testicular Germ Cell Tumor; Extragonadal Germ Cell Tumor
• Intervention / Treatment: Biological: CLDN6 CAR-T; Biological: CLDN6 RNA-LPX

Detailed Description

The study will consist of two parts. The Safety Lead-in Part will evaluate safety and tolerability of CLDN6 CAR T ± CLDN6 RNA-LPX therapy in three arms with different dosing regimens. In the Safety Lead-in Part, participants will be randomized in a 1:1:1 ratio. Data from the Safety Lead-in Part up to the cut off will be used to select the dose for the single-arm Main Part of the study.

To increase the potency of the transferred CAR-T cells, a lymphodepleting chemotherapy regimen (comprising fludarabine and cyclophosphamide) will be administered in participants prior to infusion of CLDN6 CAR-T.

It is expected that it will take approximately 28 months for each participant to complete screening, apheresis, pre-treatment, treatment, and primary follow-up.

Participants who receive a CLDN6 CAR-T infusion will complete the long-term follow-up (LTFU) to assess safety and efficacy of the CLDN6 CAR-T treatment for a total of 15 years after CLDN6 CAR-T infusion. No investigational medicinal product (IMP) will be administered during the LTFU.

• Study Type: Interventional
• Phase: Phase 2

Contacts and Locations

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Key Inclusion Criteria:

• Have a histologically confirmed diagnosis of a testicular or extragonadal GCT of extracranial origin.
• Evidence of measurable disease by RECIST 1.1 or if RECIST 1.1 evaluation is not possible, elevation of serum tumor marker(s) (AFP or βhCG).

• Participants with evidence of progressive or recurrent metastatic GCT defined as meeting at least one of the following criteria:

  • Tumor biopsy of new or growing or unresectable lesions demonstrating viable non-teratomatous GCT. In the event of an incomplete gross resection where viable GCT is found, participants will be considered eligible for this study.
  • Elevated serum tumor markers (AFP or ßhCG) that are increasing. Increase of an elevated lactate dehydrogenase alone does not constitute progressive disease.
  • Development of new or enlarging lesions in the setting of persistently elevated AFP or ßhCG, even if the markers are not continuing to rise.
• Participants must have received prior high-dose chemotherapy with autologous stem cell transplantation or conventional dose chemotherapy as salvage therapy. There is no maximum limit for the number of prior treatments.
• Have a CLDN6-positive tumor assessed using an analytically validated immunohistochemistry assay at a central laboratory.
• Have an Eastern Cooperative Oncology Group performance status of 0 to 1.
• Have laboratory tests of adequate organ function as defined in the protocol.

Key Exclusion Criteria:

• Had major surgery within the 4 weeks before the first dose of study treatment.
• Have received a prior CLDN6 CAR-T therapy.
• Are receiving systemic (oral or IV) steroid therapy >10 mg prednisolone daily, or its equivalent, for an underlying condition.
• Have unresolved side effects of any prior therapy or procedures not recovered to CTCAE version 5.0 Grade 1 or lower, except for AEs not constituting a safety risk by investigator judgment.
• Have a pure teratoma, or pure teratoma with somatic-type malignancy or a combination of these histologies without any additional histologic subtype.
• Have current evidence of active and/or uncontrolled brain or spinal metastases.
• Have an active autoimmune disease or any active immunologic disorder requiring immunosuppression with steroids or other immunosuppressive agents (protocol-defined exceptions apply). Note: Participants may be included if their disease is well controlled without the use of immunosuppressive agents, at the discretion of the investigator.
• Have a history of another primary cancer within the 24 months prior to signing the main informed consent form (exceptions for definitely treated malignancies that have been in complete remission for more than 24 months apply).
• Receipt of allogeneic stem cell transplantation in the 5 years prior to study enrollment.
• Have cardiac conditions defined as exclusionary per protocol.
• Have any concurrent conditions that could pose an undue medical hazard or interfere with the interpretation of the study results.

NOTE: Other protocol defined Inclusion/Exclusion criteria may apply.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Sequential Assignment
• Masking: None (Open Label)

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Safety Lead-in Part - CLDN6 CAR-T (dose level 1) + CLDN6 RNA-LPX	Biological: CLDN6 CAR-T; Intravenous (IV) infusion; Biological: CLDN6 RNA-LPX; IV injection
Experimental: Safety Lead-in Part - CLDN6 CAR-T (dose level 2)	Biological: CLDN6 CAR-T; Intravenous (IV) infusion
Experimental: Safety Lead-in Part - CLDN6 CAR-T (dose level 2) + CLDN6 RNA-LPX	Biological: CLDN6 CAR-T; Intravenous (IV) infusion; Biological: CLDN6 RNA-LPX; IV injection
Experimental: Main Part - Selected dose of CLDN6 CAR-T + CLDN6 RNA-LPX; Doses as selected from the Safety Lead-in Part	Biological: CLDN6 CAR-T; Intravenous (IV) infusion; Biological: CLDN6 RNA-LPX; IV injection

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Safety Lead-in Part: Occurrence of treatment emergent adverse events (TEAEs) including Grade ≥3, adverse events of special interest (AESIs) and serious or fatal TEAEs by casual relationship to study treatment	For each treatment arm	Up to 110 weeks after first dose of IMP
Main Part: Overall response rate (ORR) assessed by the blinded independent central review (BICR)	Defined as the percentage of participants in whom a confirmed complete response (CR) or partial response (PR) (per response evaluation criteria in solid tumors version 1.1 ([RECIST 1.1]) is observed as best overall response	Up to 110 weeks after first dose of IMP
LTFU: Occurrence of AEs suspected to be related to CLDN6 CAR-T	AEs may include: new malignancy (hematologic or solid) from genetically modified cells; new neurologic disorder, or exacerbation of a pre-existing disorder; new rheumatologic or autoimmune disorder, or exacerbation of a prior rheumatologic or other autoimmune disorder; new hematologic disorder; other new clinical condition considered by the investigator to be related to the prior genetically engineered T-cell therapy.	Up to 15 years after CLDN6 CAR-T administration

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Safety Lead-in and Main Part: Occurrence of TEAEs including Grade ≥3, AESIs, and serious or fatal TEAEs by casual relationship to study treatment	For each treatment arm	From first dose of IMP until 90 days after last dose of IMP, or until a new anticancer therapy is started, whichever occurs first
Safety Lead-in and Main Part: Geometric mean of pharmacokinetic parameter maximum concentration (Cmax) of CLND6 CAR-T	For each treatment arm using CLND6 CAR-T concentration in blood	Up to 97 weeks after first IMP dose
Main Part: Geometric mean of pharmacokinetic parameter Cmax of interleukin (IL)-6	From baseline until last available sample	Up to 97 weeks after first IMP dose
Safety Lead-in and Main Part: Geometric mean of pharmacokinetic parameter time to maximum concentration (Tmax) of CLND6 CAR-T	For each treatment arm using CLND6 CAR-T concentration in blood	Up to 97 weeks after first IMP dose
Main Part: Geometric mean of pharmacokinetic parameter Tmax of IL-6	From baseline until last available sample	Up to 97 weeks after first IMP dose
Safety Lead-in and Main Part: Geometric mean of pharmacokinetic parameter area under the time concentration curve (AUC) of CLND6 CAR-T	For each treatment arm using CLND6 CAR-T concentration in blood	Up to 97 weeks after first IMP dose
Safety Lead-in and Main Part: Overall response rate (ORR) assessed by the investigator	Defined as the percentage of participants in whom a confirmed complete response (CR) or partial response (PR) is observed as best overall response. Tumor response will be assessed by the investigator per RECIST 1.1. In the Safety Lead-in Part, tumor assessment will also be made based on reduction of the serum tumor marker(s) (alpha fetoprotein [AFP]/beta human chorionic gonadotropin [βhCG]).	Up to 110 weeks after first dose of IMP
Safety Lead-in and Main Part: Disease control rate (DCR) assessed by the investigator	Defined as the percentage of participants in whom a CR, PR, or stable disease (SD) is observed as best overall response. Tumor response will be assessed per RECIST 1.1. In the Safety Lead-in Part, tumor assessment will also be made based on reduction of the serum tumor marker(s) (alpha fetoprotein [AFP]/beta human chorionic gonadotropin [βhCG]).	Up to 110 weeks after first dose of IMP
Main Part: DCR assessed by BICR	Defined as the percentage of participants in whom a CR, PR, or SD is observed as best overall response. Tumor response will be assessed per RECIST 1.1	Up to 110 weeks after first dose of IMP
Main Part: Progression-free survival (PFS) assessed by the investigator	Defined as the time from first dose of CLDN6 CAR-T to progressive disease (PD) or death from any cause, whichever occurs first. Tumor response will be assessed per RECIST 1.1	Up to 110 weeks after first dose of IMP
Main Part: PFS assessed by BICR	Defined as the time from first dose of CLDN6 CAR-T to PD or death from any cause, whichever occurs first. Tumor response will be assessed per RECIST 1.1	Up to 110 weeks after first dose of IMP
LTFU: PFS assessed by the investigator	Defined as the time from first dose of CLDN6 CAR-T to first objective progressive disease per RECIST 1.1 and/or based on reduction of the serum tumor marker(s) (AFP/βhCG), or death from any cause, whichever occurs first.	Up to 15 years after the last IMP administration
Main Part: Duration of response (DOR) assessed by the investigator	Defined as the time from first objective response (CR or PR) to first occurrence of tumor progression, or death from any cause, whichever occurs first. Tumor response will be assessed per RECIST 1.1.	Up to 110 weeks after first dose of IMP
Main Part: DOR assessed by BICR	Defined as the time from first objective response (CR or PR) to first occurrence of tumor progression, or death from any cause, whichever occurs first. Tumor response will be assessed per RECIST 1.1.	Up to 110 weeks after first dose of IMP
Main Part: Overall survival (OS)	Defined as the time from first dose of CLDN6 CAR-T to death from any cause	Up to 97 weeks after first dose of IMP or until death, whichever occurs first
LTFU: OS	Defined as the time from first dose of CLDN6 CAR-T to death from any cause	Up to 15 years from last genetically engineered T-cell infusion or until death, whichever occurs first
Main Part: Percentage of participants with pre-existing anti-chimeric antigen receptor (CAR) antibodies prior to CLDN6 CAR-T infusion	For each treatment arm using CLND6 CAR-T concentration in blood and of IL-6 from baseline until last available sample	On Day 1 prior to CAR-T infusion
Main Part: Percentage of participants with treatment-emergent anti-CAR antibodies post-CLDN6 CAR-T infusion until last available sample	Anti-CAR antibodies including both treatment-induced and treatment-boosted	Up to 97 weeks after first dose of IMP

Collaborators and Investigators

• Sponsor: BioNTech SE
• Investigators: Study Director: BioNTech Responsible Person, BioNTech SE

Study record dates

Study Major Dates

• Study Start (Estimated): July 1, 2025
• Primary Completion (Estimated): June 1, 2042
• Study Completion (Estimated): June 1, 2042

Study Registration Dates

• First Submitted: April 16, 2025
• First Submitted That Met QC Criteria: April 16, 2025
• First Posted (Actual): April 23, 2025

Study Record Updates

• Last Update Posted (Actual): July 2, 2025
• Last Update Submitted That Met QC Criteria: June 30, 2025
• Last Verified: June 1, 2025

More Information

Terms related to this study

• Keywords: Immunotherapy; Salvage therapy; Testicular cancer; CLDN6-positive relapsed or refractory advanced solid tumors; Advanced germ cell tumor; Metastatic germ cell tumors; Autologous T-cells
• Additional Relevant MeSH Terms: Neoplasms by Histologic Type; Neoplasms; Neoplasms, Germ Cell and Embryonal
• Other Study ID Numbers: BNT211-02; 2024-511941-20-00 (Ctis)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No