MammaPrint Identifies Patients Who Benefit From Anthracyclines in Early-Stage Breast Cancer

At the San Antonio Breast Cancer Symposium (SABCS) in San Antonio, William Audeh, MD, presented data highlighting the clinical utility of MammaPrint in guiding anthracycline use for patients with early-stage breast cancer. The findings address an unmet need left by prior trials, including the ABC trial, which failed to clearly identify which patients benefit from anthracycline-containing regimens such as doxorubicin. Patients classified as MammaPrint High Risk 2 derived significant benefit from anthracycline therapy, while those who did not receive it experienced early relapse within three years. In contrast, patients categorized as High Risk 1 did not benefit from anthracyclines, regardless of clinical risk factors such as stage II disease or nodal positivity. These results suggest that a substantial subset of patients may safely avoid anthracycline exposure and its associated toxicities.

Pharmacy Times: At SABCS, Agendia is presenting multiple posters demonstrating how MammaPrint and BluePrint can guide treatment decisions, including the use—or avoidance—of anthracycline therapy. What do you view as the most clinically impactful insights emerging from this year’s FLEX analyses?

William Audeh, MD: Yes, well, as you just mentioned, of the several abstracts that we’re presenting this year, the abstract relating to MammaPrint’s ability to predict which patients will benefit from anthracycline, I think, is really the most important in terms of clinical application. Because MammaPrint is widely available and any doctor can order it, this is a clinical utility that can be applied Monday morning to breast cancer patients.

The question we were seeking to answer is a question that was left unanswered by large clinical trials such as the ABC trial, which sought to identify which breast cancer patients really need the addition of that somewhat toxic drug, doxorubicin, of the anthracycline family of drugs. There are really no clear guidelines, and there are no clinical indicators that identify who really benefits.

So we provided data showing that with MammaPrint, in the high-risk category known as High Risk 2, those patients really do benefit a great deal from the addition of anthracycline. Patients in that high-risk category who did not receive it were unfortunately already having early relapses within the first three years.

The other, I would say, equally important aspect is that we showed that patients who were not in that highest-risk group but were still chemotherapy candidates, High Risk 1 by MammaPrint, did not benefit from anthracycline. In fact, regardless of their clinical risk, stage II patients with positive nodes did not benefit. That is probably a bigger population than we’re showing that can avoid that toxic drug.

Pharmacy Times: MammaPrint and BluePrint are increasingly used to guide chemotherapy decisions, including whether anthracyclines are truly necessary. From your perspective, how can oncology pharmacists support clinicians in interpreting genomic assay results and ensuring patients receive the most individualized—and safest—treatment plan?

William Audeh, MD: Well, as a medical oncologist and a breast cancer specialist, I firmly believe, of course, that the oncology pharmacist is an essential member of the circle of care in the team approach to achieve the best outcomes for people diagnosed with early-stage breast cancer. The role of the oncology pharmacist, I think, is essential here because it is really the guidance coming from pharmacy that can remind clinicians of which drugs may be better suited for a particular patient and which drugs are unnecessary for a particular patient.

In my way of thinking, it’s not very different from what pharmacists have typically done in the hospital in recommending antibiotic therapy. Some antibiotics are appropriate for certain patients and not for others, and often that kind of information is not readily available to the clinician. So for the pharmacist to make clinicians aware that there is genomic information that can help guide therapy choice—if it’s available, they can help to interpret it, and if it isn’t available, they can certainly suggest that it be obtained—to make the best choice for the patient in question.