Dr Hilton on the Potential Impact of the CompassHER2-pCR Trial in HER2+ Breast Cancer

Christie J. Hilton, DO, assistant professor, Department of Medicine, Drexel University College of Medicine, director, Academic Breast Oncology, Allegheny Health Network (AHN), AHN Cancer Institute, discusses the potential impact of the ongoing phase 2 CompassHER2-pCR trial (NCT04266249) for patients with HER2-positive breast cancer.

The study is evaluating the de-escalation of further chemotherapy for patients with stage II/IIIa HER2-positive breast cancer who achieve a pathologic complete response (pCR) following surgery. All enrolled patients are receiving 4 cycles of neoadjuvant chemotherapy consisting of paclitaxel, nab-paclitaxel (Abraxane), or docetaxel in combination with trastuzumab (Herceptin) and pertuzumab (Perjeta). Patients who experience a pCR are proceeding to arm A, where they are receiving adjuvant trastuzumab plus pertuzumab for up to 13 cycles, with radiation and hormone therapy allowed, if appropriate. Patients with residual invasive disease following surgery are being given standard-of-care ado-trastuzumab emtansine (T-DM1; Kadcyla) for 14 doses with the option for chemotherapy and hormone therapy, if appropriate.

Although data have yet to read out from the study, findings could help lead to a better understanding of which patients could be candidates for de-escalated adjuvant chemotherapy, Hilton notes. This approach allows for patients who achieve a pCR to receive only 1 chemotherapy in the neoadjuvant setting before continuing targeted therapy after surgery, Hilton adds.

The results of this trial are highly anticipated and have the potential to deliver impactful results for patients with HER2-positive breast cancer, Hilton continues. Although it could be difficult to find the exact balance to know when de-escalating therapy is appropriate, CompassHER2-pCR could serve as another step toward creating response-guided therapy for patients with HER2-positive breast cancer, Hilton concludes.