FDA Approves Capivasertib for PTEN-Deficient Prostate Cancer

The Food and Drug Administration (FDA) has announced the approval of capivasertib (Truqap) in combination with abiraterone and prednisone for a specific subset of patients with prostate cancer.

This new treatment landscape targets adults with metastatic androgen pathway modulation-naïve or -sensitive (mAPMN/S) prostate cancer — a condition previously referred to as metastatic hormone-sensitive prostate cancer. For oncology nurses, the significance of this approval lies in its precision-medicine approach, as the indication is limited to patients whose tumors are PTEN-deficient.

Identifying the right patient: The role of companion diagnostics

A critical first step in the nursing workflow for this regimen is ensuring that the patient has been identified as PTEN-deficient through an FDA-authorized test. To facilitate this, the FDA simultaneously approved the VENTANA PTEN (SP218) RxDx Assay as a companion diagnostic tool.

In the clinical trial setting, PTEN deficiency was strictly defined as having 90% or more of viable malignant cells showing no specific cytoplasmic staining. Nurses should be aware that prospective central testing was utilized during the pivotal trial to confirm this status, emphasizing the need for accurate genomic or immunohistochemistry-based profiling before initiating therapy.

Clinical efficacy: The CAPItello-281 trial

The approval was based on data from CAPItello-281, a randomized, double-blind, multicenter trial involving 1,012 adults with newly diagnosed PTEN-deficient mAPMN/S prostate cancer. Patients were randomized to receive either the capivasertib-abiraterone combination or a placebo-abiraterone combination.

The primary efficacy endpoint was radiographic progression-free survival (rPFS), assessed by investigators. Results showed a statistically significant improvement for the capivasertib arm, with a median rPFS of 33.2 months compared to 25.7 months in the placebo group. This represents a hazard ratio of 0.81, though the FDA noted that overall survival data remained immature at the time of the rPFS analysis.

Nursing implications for dosing and administration

The dosing schedule for capivasertib is unique and requires thorough patient education to ensure adherence. The recommended dosage is 400 mg taken orally twice daily, approximately 12 hours apart. The medication is administered on an intermittent schedule: four days on treatment followed by three days off. This cycle continues until disease progression or unacceptable toxicity occurs.

Nurses should instruct patients that capivasertib can be taken with or without food. Additionally, this regimen must be administered alongside 1000 mg of abiraterone acetate once daily and 5 mg of prednisone once daily. To maintain castrate levels of testosterone, patients must also concurrently receive a GnRH analog or have undergone a bilateral orchiectomy.

Safety and toxicity management

Oncology nurses must be vigilant in monitoring for specific adverse events associated with capivasertib. The prescribing information contains several key warnings:

• Hyperglycemia: Nurses should monitor blood glucose levels, particularly in patients with pre-existing diabetes or those at risk.
• Diarrhea: This is a common concern with AKT inhibitors, and patients should be advised on early intervention and hydration.
• Cutaneous Adverse Reactions: Skin toxicities can occur, necessitating regular skin assessments during clinic visits.
• Embryo-Fetal Toxicity: Though less common in this patient demographic, counseling on reproductive risks is included in the warnings.

Healthcare professionals are encouraged to report any serious suspected adverse events to the FDA’s MedWatch Reporting System to continue building the safety profile of this new combination.

Reference

1. U.S. Food and Drug Administration. FDA approves capivasertib with abiraterone and prednisone for PTEN-deficient androgen pathway modulation-naïve or -sensitive prostate cancer. June 12, 2026. Accessed June 15, 2026.