A Phase III Trial of BNT324 Versus Docetaxel in Metastatic Castration-resistant Prostate Cancer

The study consists of a screening period (up to 28 days), a treatment period with 21-day cycles, and an after-treatment period that includes a 30-day safety follow-up period and a long-term survival follow-up period.

Treatment continues until the cancer clearly gets worse (in scans, based on blinded independent central review [BICR] assessment or investigator's decision), side effects become unacceptable, the participant chooses to stop, or the study ends.

Participants are put into one of two groups in a 1:1 ratio, which means they will have an equal chance to be in either treatment group, i.e., BNT324 group, or docetaxel plus prednisone/prednisolone group (current SoC). An independent committee will help ensure participant safety, by regularly reviewing safety and early results.

For each participant, the treatment and follow-up periods are projected to be up to ~58 months.

Key Inclusion Criteria:

• Are male adults (defined as ≥18 years of age or of an acceptable age according to local regulations at the time of giving informed consent).
• Must have documented progressive prostate cancer based on at least one of the following criteria:

• Serum/plasma PSA progression, by local laboratory, defined as two consecutive increases in PSA over a previous reference value, each measured sequentially at least 1 week apart. The PSA value at screening is required to be ≥1.0 ng/mL.
• Radiographic soft tissue progression as per PCWG3-modified RECIST v1.1.
• Radiographic progression of bone disease: evaluable disease or new bone lesion(s) by bone scan per PCWG3 criteria.
• Had previously received one or two prior androgen receptor pathway inhibitor treatments and experienced disease progression during or after a minimum of 8 weeks of therapy.
• Must not have received systemic cytotoxic chemotherapy, including taxane-based chemotherapy, for mCRPC.
• Must have had prior orchiectomy and/or have ongoing androgen-deprivation therapy and a castrate-level of serum/plasma testosterone (<50 ng/dL or <1.7 nmol/L). Participant being treated with luteinizing hormone-releasing hormone agonists or antagonists must continue such treatment throughout the study.
• Must have an Eastern Cooperative Oncology Group performance score of 0 or 1.

Key Exclusion Criteria:

• Have received prior treatment with B7-H3 targeted therapy, including B7-H3 ADCs.
• Have uncontrolled or significant cardiovascular disease, as defined in the protocol.
• Have a history of (non-infectious) interstitial lung disease (ILD)/pneumonitis that required steroids or have current ILD/pneumonitis.

NOTE: Other protocol defined Inclusion/Exclusion criteria apply.