This is a phase 2 research study that enrolls adult subjects with Nonseminomatous Germ Cell Tumors (NSGCT). The purpose of this study is to create a repository and explore the presence of modified T cells in the subject's plasma or tumors.

This study collects biospecimens (such as tumor tissue, blood, and modified T cells) that can be used in future research studies. The collected specimens can help to examine whether the modified T cells are present in the body and tumor. If the modified T cells are present in the body, and how long they last. They also will use the specimen to identify ways to improve treatment options for a future cancer patient.

Research with blood, tissue, or body fluids (specimens) can help researchers understand how the human body works. Sometimes researchers collect and store specimens and use them for different kinds of research or share them with other scientists; this is called a specimen repository or "biobank." Research with biospecimens might help to introduce new tests to find diseases or new ways to treat diseases.

The body has different ways of fighting infection and disease. No single way seems perfect for fighting cancer. This research study combines two different ways of fighting disease: antibodies and T cells. Antibodies are proteins that protect the body from disease caused by bacteria or toxic substances. Antibodies work by binding those bacteria or substances, which stops them from growing and causing bad effects. T cells, also called T lymphocytes, are special infection-fighting blood cells that can kill other cells, including tumor cells or cells that are infected. Both antibodies and T cells have been used to treat patients with cancers. They both have shown promise, but neither alone has been sufficient to cure most patients. This study is designed to combine both T cells and antibodies to create a more effective treatment called autologous T lymphocyte chimeric antigen receptor cells targeted against the CD30 antigen (ATLCAR.CD30) administration.

Prior trials have shown the safety of ATLCAR.CD30 product was administered to subjects with lymphomas. This study was planned based on the safety and efficacy data from previous studies (NCT02690545 and NCT02917083).

Inclusion Criteria:

1. Written informed consent and Health Insurance Portability and Accountability Act (HIPAA) authorization for the release of personal health information explained to, understood by, and signed by the subject or legally authorized representative.
2. Age ≥ 18 years at the time of consent.
3. Histologically confirmed diagnosis of Nonseminomatous Germ Cell Tumors (NSGCT) of any primary site.
4. Subjects must have received at least one prior line of therapy for their NSGCT and meet one of the following criteria. There is no maximum number of prior lines of treatment allowed.
5. Evidence of progressive or recurrent NSGCT after prior high-dose chemotherapy (HDCT) treatment, defined as meeting at least one of the following criteria: i. Tumor biopsy of new or growing or unresectable lesions demonstrating viable NSGCT. In the event of an incomplete gross resection where viable NSGCT is found, subjects will be considered eligible for the study. ii. Consecutive elevated serum tumor markers (β-HCG or AFP) are increasing. An increase of elevated lactate dehydrogenase (LDH) alone does not constitute progressive disease. iii. Development of new or enlarging lesions in the setting of persistently elevated β-HCG or AFP, even if the β-HCG and AFP are not continuing to rise.

Exclusion Criteria:

1. Subject is pregnant or lactating (Note: Breast milk cannot be stored for future use while the mother is being treated in the study).
2. Active infection with HIV, human T-cell leukemia virus, hepatitis B virus, and hepatitis C virus (tests can be pending at the time of cell procurement; only those samples confirming lack of active infection will be used to generate transduced cells). Note: To meet eligibility subjects are required to be negative for HIV antibody, negative for HTLV1 and 2 antibodies or PCR negative for HTLV1 and 2, negative for Hepatitis B surface antigen, and negative for HCV antibody or HCV viral load.