A study of benfo‑oxythiamine added to Pluvicto® in adults with advanced prostate cancer whose disease is stable after two prior Pluvicto® cycles

Prior treatment

• Is receiving concomitant anticancer therapy other than the trial interventions. This includes but is not limited to chemotherapy, targeted therapy, immunotherapy and radiotherapy. ARPis, ADTs, bisphosphonates and other supportive non-cancer directed therapies for bone conditions that started before trial entry may be continued. Palliative radiotherapy for bone pain is allowed provided it doesn’t include measurable lesions within the radiation field
• Has received an investigational medicinal product or investigational medical device within 4 weeks or within 5 half-lives (whichever is shorter) before the first B-OT dose
• Has symptomatic or untreated/unstable cord compression, central nervous system (CNS) or leptomeningeal metastases. Subjects with current or history of CNS or leptomeningeal metastases during screening may be eligible if they have received brain directed therapy and have stable brain metastases on imaging performed within 4 weeks of starting B‑OT treatment and have no neurological symptoms; and are not receiving steroid or anticonvulsant therapy for brain metastases

Other illness

• Has a radiographic CR, PR, or progressive disease according to RECIST 1.1 on contrast-enhanced, high-resolution CT performed as SOC after completion of the first 2 cycles of SOC Pluvicto® therapy, compared with SOC pre-treatment contrast-enhanced, high-resolution CT
• Has a PSMA-PET progressive disease not requiring confirmation according to PCWG4-adapted progression criteria, defined as ≥ 6 new PSMA-avid bone, nodal, or pulmonary lesions, or any single new PSMA-avid liver or other non-pulmonary visceral lesion representing disease after completion of the first 2 cycles of SOC Pluvicto® therapy, compared with SOC pre-treatment PSMA-PET
• Has persistent toxicities of at least grade 2 (CTCAE v6.0) considered related to previous cancer therapy (including the first 2 cycles of SOC Pluvicto® therapy), excluding alopecia and other stable grade 2 toxicities considered acceptable by the Investigator
• Has a history of other malignancies within the previous 2 years of starting B-OT treatment, other than basal-cell or squamous cell carcinomas of the skin
• Is unable to swallow orally administered medications or has gastrointestinal disorders likely to interfere with the absorption of the trial medication
• Has known hypersensitivity to B-OT or any of the excipients of B-OT

Lab values

• Has clinically significant abnormal ECG findings, including average corrected QT interval using Fridericia’s formula (QTcF) > 470 ms, or a history of Torsade de Pointes
• Has received a transfusion or growth factor support administered solely for the purpose of meeting eligibility laboratory thresholds, if performed up to 4 weeks before the first B-OT dose

• Is willing and able to read, understand and provide informed consent
• Has an Eastern Cooperative Oncology Group (ECOG) performance status of 0 to 2
• Has a life expectancy of at least 3 months, as evaluated by the Investigator
• Is at least 18 years of age at the time of signing the informed consent
• Has a documented histologically confirmed adenocarcinoma of the prostate
• Has a diagnosis of mCRPC with castrate serum testosterone <50 ng/dL (<1.7 nmol/L) and/or use of concomitant androgen deprivation therapy (ADT), including gonadotropin-releasing hormone analogues or antagonists, or prior bilateral orchiectomy
• Has a PSMA-positive disease confirmed on PSMA-PET/CT prior to trial entry, consistent with the approved use of Pluvicto® and local SOC procedures
• Has received prior androgen receptor pathway inhibition (ARPi) and taxane-based chemotherapy, consistent with the approved use of Pluvicto®
• Has completed the first 2 cycles of SOC Pluvicto® therapy and, in the opinion of the Investigator, remains clinically eligible for continuation of additional SOC Pluvicto® cycles
• Has stable disease according to RECIST 1.1 on contrast-enhanced, high-resolution CT performed as SOC after completion of the first 2 cycles of SOC Pluvicto® therapy, compared with SOC pre-treatment contrast-enhanced, high-resolution CT
• Has at least 1 metastatic lesion (measurable per RECIST 1.1) documented on contrast-enhanced high-resolution CT scan performed as SOC after completion of the first 2 cycles of SOC Pluvicto® therapy