On the eve of medical device and pharmaceutical giant Abbott Laboratories' announcement of a $21 billion acquisition of cancer screening company Exact Sciences, the latter is further deepening its presence in genetic testing, aiming to fulfill the promise of precision oncology and help drugmakers bring new therapies to market.

Exact recently launched Riskguard, a hereditary cancer test in the U.S., designed to identify genetic risk for 11 tumor types, including breast cancer, which remains the most commonly diagnosed cancer worldwide. Riskguard includes what the company calls the STAT breast cancer panel, which Dr. Rick Baehner, Exact's chief medical officer of precision oncology, says will help doctors assess the most effective surgical and treatment options earlier.

Germline and somatic testing together provide researchers with the insights needed to discover new targets and develop more targeted drugs, which are more efficient than broad-spectrum interventions like chemotherapy and surgery. These tests also contribute to population-level evidence, helping drugmakers better understand the complexity of specific cancer types.

Other collaborations between large pharmaceutical companies and diagnostics firms include Roche's $200 million licensing deal last year with cancer blood testing company Freenome to expand technology collaboration and develop and commercialize cancer screening tests outside the U.S.

Baehner noted that information gleaned from these tests—especially regarding various breast cancer subtypes and their corresponding drugs—helps tailor more personalized treatment plans and improve patient outcomes.

Below, Baehner discusses Exact's expanding breast cancer genetic testing portfolio, oncology's shift toward precision medicine, and the next generation of therapies.

This interview has been edited for length and style.

PHARMAVOICE: How does the ongoing genomics revolution align with Exact Sciences' goals in oncology?

Dr. Rick Baehner:Clearly, we need genetic testing to understand an individual's inherited baseline risk and whether these genes might affect the extent of surgery a patient needs. What we really want to do is build a platform that allows physicians to make clinical decisions seamlessly. Doctors tell us they need to eliminate the cumbersome processes of filling out forms and storing tumor tissue. We are seeing increasing maturity, especially in breast cancer and other tumor types, where hereditary risk testing and understanding molecular residual disease (MRD) through comprehensive genomic profiling are critical for developing clinical guidelines for physicians.

How has the breast cancer treatment landscape changed through knowledge gained from screening processes, new biomarkers, and genetic testing?

Over about 25 years, identifying different breast cancer subtypes—such as ER-positive (luminal), HER2-positive, triple-negative, and basal-like—as well as overexpression or underexpression of specific genes, has enabled us to conduct clinical trials integrating genomic markers and significantly reduce the amount of chemotherapy patients receive. We have witnessed the evolution of targeted therapies like PARP inhibitors, whose efficacy is built on identifying BRCA gene mutations and their evolution within tumors. This is an example of biomarkers having a significant impact beyond standard chemotherapy.

In HER2-positive breast cancer, there are also many remarkable therapies. Trastuzumab (Roche's Herceptin) was a disruptive drug targeting this receptor, and we increasingly see the development of antibody-drug conjugates (ADCs), combining chemotherapy drugs with monoclonal antibodies for more precise delivery; immune checkpoint inhibitors have also brought significant survival improvements in triple-negative breast cancer. The prognosis for these two cancer subtypes was once very poor.

How do these advances impact the overall healthcare landscape, especially in getting patients the right treatment earlier to save time and costs?

Exact's Oncotype DX Breast Recurrence Score test, which I helped develop 20 years ago, recently surpassed the 2 million patient milestone and has played a key role in personalizing breast cancer treatment. We estimate it has helped about 1.6 million patients safely avoid unnecessary chemotherapy. In terms of cost savings, this involves billions of dollars. In the U.S. alone, real-world evidence suggests the test may have saved the U.S. healthcare system over $14 billion. As the only predictive test on the market for adjuvant treatment and treatment decisions in ER-positive breast cancer, identifying which patients will benefit and which will not is crucial for payers and regulators, who require two decades of clinical evidence accumulated in large trials. It is this evidence across a broad patient population that underpins treatment de-escalation and generates enormous cost savings.

How do diagnostics companies like Exact collaborate with pharmaceutical companies developing new drugs?

Pharmaceutical companies increasingly rely on Exact Sciences for information such as genomic discoveries. They want to understand tumor mutations important for their targeted therapies, especially when testing new targets. We can provide RNA sequencing results that offer a unique view inside tumor cells. This allows them to extract the maximum amount of information from tumor samples to guide trials and conduct next-generation research to develop drugs.

In lung cancer, for example, initially only histology distinguished non-small cell lung cancer from small cell lung cancer; later, it was recognized that specific cell types not only correspond to specific drug development but also suggest whether drugs for other tumor types might be effective. HER2 mutations in lung cancer are a great example, with more than 10 targeted therapies now available. Colorectal cancer is also raising similar questions, where a more comprehensive understanding of tumors in the context of single-marker and drug testing provides fertile ground for studying cross-tumor therapy synergies.

What changes in integrating genomic sequencing and other cutting-edge technologies in oncology excite you most?

Looking to the future of cancer treatment and patient care, molecular residual disease testing is extremely exciting. It provides an additional layer of insight to identify patients at higher risk of recurrence—information useful not only for current physicians but also for predicting whether metastatic disease might develop in the future. The pharmaceutical industry is highly interested in identifying high-risk patients after standard chemotherapy, and MRD testing can do this because such patients are ideal candidates for advancing therapies from the metastatic setting to the adjuvant setting. Applying these powerful targeted therapies earlier in treatment is very promising.