Phase III Trial Update on Ipatasertib Plus Abiraterone in Metastatic Prostate Cancer
Posted: Friday, April 2, 2021
Updated results from the IPATential150 trial demonstrated further support for the AKT inhibitor ipatasertib plus abiraterone in the treatment of metastatic castration-resistant prostate cancer, according to Johann S. de Bono, FRCP, MB, MD, PhD, of The Institute of Cancer Research and the Royal Marsden Hospital, London, United Kingdom. He presented these findings on behalf of his colleagues at the virtual edition of the 2021 Genitourinary (GU) Cancers Symposium (Abstract 13).
“What you see quite clearly is that the more PTEN loss in the tumor, the more…benefit from the combination arm,” Dr. de Bono said in the ASCO Daily News. “The question with all of these predictive biomarkers is how to define a binary cutoff,” he noted. “Cancer is not a binary disease; it’s a continuous variable.”
The updated results of this phase III trial revealed that a consistent benefit with the combination treatment was observed when PTEN loss via immunohistochemistry status was defined more stringently using the SP218 PTEN immunohistochemistry antibody. It should be noted that the combination treatment was not associated with improved radiographic progression-free survival in patients with intact PTEN, as seen via immunohistochemistry analysis.
The analysis found that the combination of ipatasertib and abiraterone was superior with regard to radiographic progression-free survival in patients with PTEN loss, as measured by next-generation sequencing. Furthermore, it also offered significant benefit in the group of patients with other PIK3CA/AKT1/PTEN alterations, as determined by next-generation sequencing.
The researchers examined outcomes based on next-generation sequencing. Of 1,104 patients, next-generation sequencing was evaluable for 743 patients, and PTEN loss via next-generation sequencing was evaluable in 518 patients.
Disclosure: For full disclosures of the study authors, visit coi.asco.org.
