Results at ESMO Focus on Companion Diagnostics, Avoiding Overtreatment in Prostate Cancer

Myriad Genetics Inc has announced 3 poster presentations that will be featured at the 40th meeting of the European Society for Medical Oncology, which opens today in Vienna, Austria, and runs through Monday.

Identifying HRD Positive Patients. The first poster, to be presented Saturday, presents results from 318 patients enrolled in the NOVA study, a phase 3 clinical trial evaluating the PARP inhibitor niraparib as a treatment in patients with platinum-sensitive ovarian cancer. Results showed 100% of patients with a germline BRCA mutation and 55% of patients without a BRCA mutation were HRD positive as determined by the myChoice HRD test.

The myChoice HRD test employs 3 unique algorithms of DNA damage: LOH, LST, and TAI. The study showed that the test more clearly defined the HRD positive population in ovarian cancer than LOH alone. The results support using the myChoice HRD to identify those patients who may respond to treatment with platinum drugs and PARP inhibitors.

Next-Generation Sequencing. A second poster scheduled for presentation Saturday features results on Tumor BRACAnalysis CDx. This is a tumor-based next generation sequencing test to detect germline BRCA 1/2 mutations in patients who have high-grade serous ovarian cancer and the results compared how it functioned compared with germline testing using Sanger sequencing in a reference laboratory. The new test was evaluated with tissue from 54 patients, in all cases, the new test correctly identified the harmful BRCA 1/2 mutations, showing 100% sensitivity. In addition, the study revealed that tumor cells have de novo somatic mutations that cannot be found by germline testing alone. Patients with germline and tumor BRCA 1/2 mutations had similar responses to olaparib, which suggests that the tumor test is effective for identifying patients who are appropriate for treatment with PARP inhibitors.

Avoid Prostate Cancer Overtreatment. Scheduled for Monday, this poster presents results of the EMPATHY-P study involving 502 patient biopsy samples from 5 European countries. The study sought to gauge the aggressiveness of prostate cancer in newly diagnosed patients, using both standard clinical pathology methods and the Prolaris test. The study showed that Prolaris gave the European men a different risk profile than standard methods 54% of the time; 24% had less aggressive cancer and 30% had more aggressive cancer. The data show that the Prolaris score can be used to identify men with localized prostate cancer who are candidates for active surveillance, and thus avoid more aggressive treatment than is necessary.

References

European Society of Medical Oncology; September 25-29, 2015; Vienna, Austria. Posters P108, P116, P072.