A Phase II Study Evaluating T-Cell Clonality After Stereotactic Body Radiation Therapy Alone and in Combination With the Immunocytokine M9241 in Localized High and Intermediate Risk Prostate Cancer Treated With Androgen Deprivation Therapy
Background: Prostate cancer is often treated with radiation and ADT (ADT is androgen deprivation therapy). Up to 30% of these cancers recur within 5 years of treatment. Researchers want to see if a new drug (M9241) can help the immune system to fight prostate cancer.
Objective: To find what doses of M9241 are safe in people who are treated for prostate cancer. Also, to see what effects M9241 has on the immune system.
Eligibility: People aged 18 and older with high- and intermediate-risk prostate cancer. Their cancer must not have spread to other parts of the body.
Design: The study will last 7 months. Participants will be screened. They will share their medical history. They will also have: \<TAB\>A physical exam \<TAB\>Routine blood and urine tests \<TAB\>Imaging scans of the chest, abdomen, and pelvis \<TAB\>A bone scan \<TAB\>A tumor biopsy \<TAB\>A specialized MRI. Participants will lie face down on the MRI scanner table. An antenna that receives a signal may be placed in the rectum. All participants will be treated with radiation therapy and ADT. Some participants will also receive M9241 as an injection under the skin. This treatment will start 4 weeks after the radiation has ended. Participants will receive a total of 3 doses. The injections will be 4 weeks apart. Some screening tests will be repeated at each visit. Participants who do not receive M9241 will also have screening tests during the treatment period. Participants will return for follow-up about 1 month after the last treatment or set of tests.
• Participants must have histologically or cytologically confirmed localized intermediate or high risk prostate cancer:
‣ Intermediate risk - Gleason 7 disease, PSA less than 10
⁃ High Risk - Gleason 8-10, PSA\>10, Extracapsular Extension
• Participants must require treatment with SBRT to the prostate and ADT.
• Pre-treatment tissue availability (collected \<= 1 year to initiation of study therapy) for biomarker analysis is mandatory for enrollment. If tissue is determined to be of insufficient/unsuitable quality/quantity, a pre-treatment biopsy prior to initiation of study therapy will be required.
• Male age \>= 18 years old
• ECOG performance status \< 2
• Participants must have adequate organ and marrow function as defined below:
‣ absolute neutrophil count \>= 1,500/mcL, without CSF support
⁃ platelets \>= 100,000/mcL
⁃ AST(SGOT)/ALT(SGPT) \<= 2.5 X institutional upper limit of normal
⁃ Hgb \>= 10g/dL (pRBC transfusions are not allowed to achieve acceptable Hgb)
⁃ Total bilirubin \<= 1.5 x upper limit of normal (ULN),
∙ OR
∙ in participants with Gilbert s syndrome, a total bilirubin \<= 3.0
• Serum albumin \>= 2.8 g/dL
• Creatine \<= 1.5 X institutional ULN
∙ OR
• Creatinine clearance \>= 50 mL/min/1.73 m\^2 for participants with creatinine levels above institutional normal by 24h urine
• PT/INR and aPTT \<= 1.5 X institutional ULN
‣ Testosterone greater than 100 ng/dL.
⁃ Men must agree to use adequate contraception (hormonal or barrier method of birth control; abstinence) after study entry and for 6 months after completion of radiation treatment or immunotherapy (if taken, whatever is last)
⁃ Participants must have prostate cancer accessible for biopsy
⁃ Ability of participant to understand and the willingness to sign a written informed consent document.