The purpose of this study is to learn about- for how long are NHTs taken by men to treat mCSPC. NHTs in this study include study medicines:

• abiraterone,
• apalutamide,
• enzalutamide.

Prostate cancer is one of the most common cancers in men. The prostate is a gland in the male body that helps make semen. Metastatic cancer is a cancer that has spread to other parts of the body. Most prostate cancers need male hormones to grow. When cancer cells respond to treatment that lowers male hormones, this is known as castration-sensitive prostate cancer.

This is a real-world study, not a clinical trial. This means that researchers will look at what happens when men receive the treatments prescribed by their own doctor as part of their usual healthcare treatment. In this study, researchers will use information from National Veteran's Affairs (VA) Health Care Network.

The study will include patients' information from the database for men who:

• were identified to have mCSPC.
• started treatment with NHT for mCSPC.
• were 18 years of age or older at start of NHT.

Men in this study will be taking NHT for treatment of their mCSPC. The study will explain:

• how long men take the therapy.
• how long it takes to start next therapy.

This study will use patient information about medications and treatments from VA data. This study will use information one year before start of NHT until information is available.

Inclusion Criteria:

• Male with ≥ 1 diagnosis claim for prostate cancer

• Had documented secondary metastasis code on or after the initial prostate cancer diagnosis

• Had initiated novel hormonal therapy (abiraterone, apalutamide, or enzalutamide) within 90 days prior to the metastasis date or on or after the metastasis date. The initiation date of the earliest novel hormonal therapy will be defined as the index date

• ≥18 years old on index date

• Continuous enrollment for at least 365 days before index date

• Evidence to be castration-sensitive:

  • No prior surgical castration any time prior to the index date or no medical castration with ≥8 weeks of continuous use within -90 to -365 days prior to the index date, OR
  • Diagnosis of hormone sensitive malignancy status within 90 days before the index date

Exclusion Criteria:

• Evidence of castration-resistance prior to the index date

  • Received other prostate cancer treatment including NHT, non-steroidal anti-androgen (NSAA), chemotherapy, immunotherapy, radium 223, lutetium Lu 177 vipivotide tetraxetan, ketoconazole, or PARP inhibitor prior to the index date
  • Had diagnosis code indicating hormone resistance prior to the index date
  • A rise in prostate-specific antigen from the nadir by ≥2 ng/mL after castration

• Had a prior history of other cancers (except non-melanoma skin cancer)

• Participation in a clinical trial during the 30 days before the index date

Men with metastatic castration-sensitive prostate cancer who initiated novel hormonal therapy (abiraterone, apalutamide, or enzalutamide) and met eligibility criteria will be included in the study. Patients will be identified from the National Veterans Affairs Health Care Network.

Pfizer will provide access to individual de-identified participant data and related study documents (e.g. protocol, Statistical Analysis Plan (SAP), Clinical Study Report (CSR)) upon request from qualified researchers, and subject to certain criteria, conditions, and exceptions. Further details on Pfizer's data sharing criteria and process for requesting access can be found at: https://www.pfizer.com/science/clinical\_trials/trial\_data\_and\_results/data\_requests.