· Updated TAILORx follow-up data showing the integration of clinico-pathologic criteria and Recurrence Score® results to refine distant recurrence risk estimates

· New concordance analysis supporting the generation of Oncotype DX® results from core needle biopsy to personalize treatment decisions

· ADAPTcycle trial data, using Oncotype DX results and endocrine response to stratify patients, may expand the number of breast cancer patients able to forgo chemotherapy post-surgery; data chosen as late-breaking abstract  

· Prospective trial data regarding the potential omission of radiation therapy after surgery in certain patients with ductal carcinoma in situ (DCIS) chosen for press program

MADISON, WIS., Nov. 30, 2023 —Exact Sciences Corp. (NASDAQ: EXAS), a leading provider of cancer screening and diagnostic tests, will present new data and study results across its Precision Oncology and hereditary cancer platforms at the 2023 annual San Antonio Breast Cancer Symposium (SABCS).

“Exact Sciences is looking forward to presenting new evidence at SABCS that adds important perspectives to treating breast cancer patients and showing that some patients may be able to de-escalate treatments and still have positive outcomes,” said Dr. Rick Baehner, Chief Medical Officer, Precision Oncology, Exact Sciences. “Every year, we build upon the precedent set by the Oncotype DX Breast Recurrence Score® test and its prognostic and predictive abilities to determine the chemotherapy benefit for specific breast cancer patients. We are pleased to see authorities expanding access to this test as we continue to develop key evidence in collaboration with some of the world’s most prestigious, breast cancer-focused organizations.”

In cooperation with several leading breast cancer research organizations, Exact Sciences will present late-breaking data and a study included in the SABCS press program. Results from Puerto Rico will also detail germline findings for a cohort of women, most of whom had a personal or familial history of breast cancer. The results suggest a distinct genetic background for hereditary cancer predisposition in the study population.

Exact Sciences will also host a discussion about the Oncotype DX Breast Recurrence Score test and the RSClin Tool. Christy Russell MD, VP Medical Affairs, Exact Sciences, Jennifer Racz, MD. Director, Oncology Medical Affairs, Exact Sciences and Jay Andersen, MD, Co-Director, Compass Breast Specialists and Associate Chair, US Oncology Breast Cancer Research Committee, will review the development and validation of the RSClin® Tool in patients with node-negative, early-stage breast cancer and as well as discuss its utility for patients and providers.
The discussion will take place:

When: Thursday, December 7th, 4:00-5:00 pm CT
Where: Exhibit Hall Product Theater A, Henry B. Gonzalez Convention Center, San Antonio, Texas

Exact Sciences will present the following data at SABCS 2023:

1. Title: Magnetic Resonance Imaging and a 12-Gene Expression Assay to Optimize Local Therapy for Ductal Carcinoma In Situ: 5-year clinical outcomes of E4112 - Chosen for SABCS Press Program
Summary: This prospective trial, the first to evaluate the predictive ability of the 12-gene DCIS score, provides data regarding the omission of radiation therapy after surgery in patients with DCIS breast cancer who have low DCIS score results, and the benefit of radiation therapy in patients with intermediate/high DS results.
Oral Presentation ID: GS03-01: Friday December 8, 2023, 8:15-11:15 am

2. Title: Impact of age and ovarian function suppression (OFS) on endocrine response to short preoperative endocrine therapy (ET): Results from the multicenter ADAPTcycle trial
Chosen as Late Breaking Abstract at SABCS
Data embargoed until: 7:15 am CT on Friday, December 8
Presentation ID: LBO1-05: Friday December 8, 2023, 12-12:45 pm

3. Title: Comparison of whole exome, whole transcriptome genomic profiling and targeted sequencing with 50-gene panels
Summary: A comparison of the OncoExTra™ whole-exome, whole-transcriptome, comprehensive genomic profiling test to three commercially available and one custom 50-gene panels in a cohort of breast cancer patients. The study determined the frequency of patient tumors that would have had no actionable alteration identified when employing each of the 50-gene panels, when an actionable alteration identified by the OncoExTra test was present, across the three different breast cancer subtypes. The highest proportion of patients was missed (no actionable finding) by 50-gene panels when the cancer was the TNBC subtype and the lowest for HER2+.
Presentation: Poster I D PO5-13-05: Friday Dec 8, 12-2pm (poster session 5)

4. Title: Classifying HER2-low breast cancer using a combination of ERBB2 mRNA expression and altered genes
Summary: Comparison of ERBB2 gene expression, measured using mRNA levels, with HER2 (encoded by ERBB2 gene) protein expression, measured by IHC/FISH. A comparison of altered biomarkers across HER2 protein expression categories was also made. ERBB2 expression levels and alterations in selected biomarkers were used to train a logistic regression classifier to predict HER2 protein expression status. Preliminary results indicate that some HER2-0 samples were classified as HER2-low by the classifier.
Presentation: Poster ID P05-13-06: Friday Dec 8, 12-2pm (poster session 5)

5. Title: Prevalence of genomic alterations in Xerna tumor microenvironment subtypes in triple negative breast cancer patients
Summary: 203 triple negative breast cancer tumor samples were assigned to four different Xerna tumor-microenvironment categories (high versus low immune score, high versus low angiogenic score) based on gene expression of about 100 genes. The prevalence of actionable alterations in biomarkers was then determined across these four tumor microenvironment subtypes. About half of cancer samples had high immune scores, suggesting possible response to ICI therapy. More than half of patient samples carried actionable alterations. Together, these findings suggest possibility of novel combination therapies in some TNBC patients.
Presentation: Poster ID PO2-06-10: Wednesday Dec 6, 5-7pm (poster session 2).

6. Title: Hereditary cancer genetic testing in Puerto Rican females
Summary: Nearly one thousand Puerto Rican females tested with a hereditary cancer panel containing 29 genes. 90 (9.5%) individuals had a pathogenic or likely pathogenic alteration in their germ line at one or more of these genes. Proportion of individuals carrying a pathogenic/likely pathogenic variant at a cancer gene is within the range reported for other Caribbean countries. However, there was no evidence for enrichment of alterations at BRCA1, BRCA2 and PALB2 as observed in other Caribbean countries. The study also denotes a lack of genetic testing amongst specific disparate populations.
Presentation: Poster ID: PO1-08-08: Wednesday December 6, 2023, 12:00 PM - 2:00 PM Poster Session 1

7. Title: Concordance Study of Oncotype DX Breast Recurrence Score® Results from Paired Breast Cancer Core Needle Biopsies and Surgical Excision Specimens
Summary: Comparison of Oncotype DX Recurrence Score results for paired core needle biopsy and surgical samples of the same tumor without intervening systemic therapy, which found high concordance between the two.
Presentation ID: PO4-08-09: Thursday December 7, 2023, 5-7 PM

8. Title: Comparison of the cost-effectiveness of multigene assays for HR+/HER2- node-negative early-stage breast cancer in the US
Summary: Compares the cost-effectiveness of using different genomic assays for treatment decisions in HR+HER2- early breast cancer (Oncotype DX, MammaPrint, EndoPredict, and Prosigna ROR) relative to that of using clinical-pathological features alone in the U.S. The modeling found that all were cost-effective as additions to clinical-pathological features, with the Oncotype DX test providing the greatest cost savings among the four.
Presentation ID: PO1-01-10: Poster Session 1, Wednesday December 6, 2023, 12 -2 PM

9. Title: A comparison of chemotherapy recommendations by NPI, Predict, and Oncotype DX   
testing in UK women with early node-positive breast cancer
Summary: Comparison of the Oncotype DX Recurrence Score test, the Nottingham Prognostic Index, and the Predict Breast Cancer tool in risk stratification and association with chemotherapy recommendations in HR+HER2- node-positive early breast cancer. Of the three, the Oncotype test was the most strongly associated with chemotherapy recommendation.
Presentation ID: PO1-14-05: Wednesday December 6, 2023, 12 – 2 pm

10. Title: Update of RSClin tool with extended TAILORx follow-up and development and validation of a new tool for risk of late distant recurrence
Summary: Update of the TAILORx findings with longer follow-up and resulting refinements to the RSClin tool for estimating 10-year risk of distant recurrence in HR+HER2- early breast cancer. A new tool specifically to estimate late (5-10 year) distant recurrence risk is also presented.
Presentation ID: PO1-02-02: Poster Session 1, Wednesday December 6, 2023, 12 – 2 pm

11. Title: Irish National Analysis of the Clinical and Economic impact of 21-gene Oncotype DX® testing in Early-Stage, 1-3 lymph node-positive, Hormone Receptor positive (HR+), HER2-Negative (HER2-), Breast Cancer (BC)
Summary: An analysis of the impact of Oncotype DX® testing in a N1 (disease with 1-3 positive LN) breast cancer population from 2 Irish cancer centers identified a 55% reduction in chemotherapy use with savings of over €1 million. The objectives of this study were to examine the clinical and economic impact of Oncotype DX testing on treatment decisions in N1 patients at a national level with a larger patient population, and to examine changes in the ordering of Oncotype DX tests pre and post-RxPONDER data. This study extended the analysis to 5 Irish cancer centers.
Presentation ID: PO5-02-04: Friday, December 8, 2023, 12 - 2pm

12. Title: Real-world application of a 21-gene recurrence score in a Swiss single1center breast cancer population. A comparative analysis of treatment administration before and after TAILORx
Summary: A comparison of chemotherapy recommendations and use before and after TAILORx.There were some differences in treatment recommendations after TAILORx that included increased recommendation for addition of chemotherapy to endocrine therapy, specifically among younger women, but there were no significant changes in chemotherapy administration.
Presentation ID: Poster Number: P1-14-02: Wednesday December 6, 2023, 12 - 2 pm

About Exact Sciences Corp. 
A leading provider of cancer screening and diagnostic tests, Exact Sciences gives patients and health care professionals the clarity needed to take life-changing action earlier. Building on the success of the Cologuard® and Oncotype® tests, Exact Sciences is investing in its pipeline to develop innovative solutions for use before, during, and after a cancer diagnosis. For more information, visit ExactSciences.com, follow Exact Sciences on X, formerly known as Twitter @ExactSciences, or find Exact Sciences on LinkedIn and Facebook.

NOTE: Exact Sciences™ is a registered trademark of Exact Sciences Corporation. Oncotype™ and OncoExTra™ are registered trademarks of Genomic Health, Inc., a wholly-owned subsidiary of Exact Sciences Corporation. All other trademarks and service marks are the property of their respective owners.

Forward-Looking Statements
This news release contains forward-looking statements concerning our expectations, anticipations, intentions, beliefs, or strategies regarding the future. These forward-looking statements are based on assumptions that we have made as of the date hereof and are subject to known and unknown risks and uncertainties that could cause actual results, conditions and events to differ materially from those anticipated. Therefore, you should not place undue reliance on forward-looking statements. Examples of forward-looking statements include, among others, statements we make regarding the development and commercialization of the next-generation Cologuard™ test; the performance characteristics of next-generation Cologuard™ in a commercial setting; and the timing and anticipated results of additional analysis of the BLUE-C data and FDA submission. Risks and uncertainties that may affect our forward-looking statements are described in the Risk Factors sections of our most recent Annual Report on Form 10-K and any subsequent Quarterly Reports on Form 10-Q, and in our other reports filed with the Securities and Exchange Commission. We undertake no obligation to publicly update any forward-looking statement, whether written or oral, that may be made from time to time, whether as a result of new information, future developments or otherwise.

Media Contact (U.S.):
Jack Hirschfield
+1 608-852-9877
jhirschfield@exactsciences.com

Media Contact (OUS):
Federico Maiardi
+41 79-138-1326
fmaiardi@exactsciences.com

Investor Contact:
Erik Holznecht
608-800-6605
investorrelations@exactsciences.com