Clinical Study on the Efficacy and Safety of RC48-ADC in the Treatment of Metastatic Castration Resistant Prostate Cancer (mCRPC)

An Open, Single Arm, Single Center Phase II Clinical Study Evaluating the Efficacy and Safety of RC48-ADC in the Treatment of Metastatic Castration Resistant Prostate Cancer (mCRPC) Progression After Novel Endocrine Therapy

This is a single-arm, open, single-center clinical study to evaluate the efficacy and safety of RC48-ADC in patients with mCRPC who have progressed after NHT. A total of 40 patients with mCRPC with immunohistochemically confirmed HER2 expression who had progressed after treatment with at least one novel endocrine therapy will be included in this study.

This is a single-arm, open, single-center clinical study to evaluate the efficacy and safety of RC48-ADC in patients with mCRPC who have progressed after NHT. A total of 40 patients with mCRPC with immunohistochemically confirmed HER2 expression who had progressed after treatment with at least one novel endocrine therapy will be included in this study. Participants will receive RC48-ADC intravenous injection (2.0 mg/kg, Q2W) until disease progression or death. During the treatment, participants will evaluate every 4 weeks, including PSA testing every 4 weeks and tumor evaluation according to PCWG3 standards every 8 weeks. If the patient develops disease progression, the treatment will be discontinued and survival follow-up will be conducted every 8 weeks.

Inclusion Criteria:

• 1) Prostate cancer confirmed by histology;
• 2) ≥ 18 years old;
• 3) The presence of metastatic lesions confirmed by bone scan and/or CT/MRI and/or PET-CT;
• 4) ECOG score 0-2;
• 5) Continuously maintain ADT treatment and maintain testosterone levels ≤ 50ng/dL; The progression of prostate cancer recorded within 6 months prior to screening;
• 6) Having received at least one NHT in the past before progressing;
• 7) HER2 IHC 1+, 2+, or 3+;
• 8) Inability to or refusal docetaxel chemotherapy;
• 9) Voluntarily join the study;
• 10) Expected survival time ≥ 6 months;
• 11) Normal function of main organs;

Exclusion Criteria:

• 1)Have a history of malignant tumors other than prostate cancer;
• 2)Previously received allogeneic stem cell or parenchymal organ transplantation;
• 3) Previously or currently suffering from congenital or acquired immunodeficiency diseases;
• 4) The patient have a history of allergy to RC48 or paclitaxel, or a history of Hypersensitivity to chimeric or humanized antibodies or fusion proteins, or allergy to excipients of the study drug;
• 5) Other significant clinical and laboratory abnormalities that affect safety evaluation;
• 6) Those who are unwilling or unable to take effective contraceptive measures;
• 7) Subjects with active brain metastasis;