Patients with Uveal Melanoma Tested with DecisionDx®-UM Report Gaining Value from Test Results In Study Conducted In Collaboration with the Melanoma Research Foundation’s CURE OM Initiative

Data shows patients surveyed had low decision regret¹ after testing with DecisionDx^®-UM, regardless of whether their uveal melanoma tumor was at high or low risk of metastasis

Castle Biosciences, Inc. (Nasdaq: CSTL), a company improving health through innovative tests that guide patient care, today announced findings from a study that evaluated uveal melanoma (UM) patients’ attitudes toward prognostic testing and specifically with respect to DecisionDx-UM^®. Highlights from the study were shared in a poster presentation at the 20th congress of the International Society of Ocular Oncology (ISOO), recently held in Leiden, The Netherlands.

The poster, titled “Uveal Melanoma Patient Attitudes Towards Prognostic Testing Using Gene Expression Profiling” and presented by Basil K. Williams, Jr., M.D., assistant professor in the Department of Ophthalmology and Mary Knight Asbury Chair of Ocular Oncology at the University of Cincinnati College of Medicine, can be viewed here.

“Most patients impacted by the rare but quite deadly disease, uveal melanoma, want and expect to play an active role in their care to ensure the best possible outcome,” said Williams. “We believe the survey data supported this sentiment and found that regardless of their overall prognosis, patients value the information provided by their DecisionDx-UM test results.”

Study highlights:

• An online questionnaire was distributed by the Melanoma Research Foundation’s CURE OM (Ocular Melanoma) initiative to capture anonymous information regarding patient-reported experiences following prognostic testing.
• Patients were asked questions regarding the decision to undergo prognostic testing and the extent to which they felt decision regret.
• Of the 177 survey participants, 90% reported wanting prognostic information at diagnosis.
• Of the patients who received prognostic testing with DecisionDx-UM, there was no significant difference in decision regret levels among those receiving a low- (Class 1A), intermediate- (Class 1B) or high-risk (Class 2) test result (Kruskal-Wallis rank sum test, X²=4.1, p=0.13).
• Patients tested with DecisionDx-UM reported gaining value from their test result, including:
  • Increased knowledge and understanding of their disease
  • More personalized treatment options
  • Information relevant to life planning
  • Relief from uncertainty about the future

About DecisionDx^®-UM

DecisionDx-UM is Castle Biosciences’ 15-gene expression profile (GEP) test that uses an individual patient’s tumor biology to predict individual risk of metastasis in patients with uveal melanoma. DecisionDx-UM is the standard of care in the management of newly diagnosed uveal melanoma in the majority of ocular oncology practices in the United States. Since 2009, the American Joint Committee on Cancer (AJCC; v7 and v8) Staging Manual for UM has specifically identified the GEP test as a prognostic factor that is recommended for collection as a part of clinical care. Further, the National Comprehensive Cancer Network (NCCN) guidelines for uveal melanoma include the DecisionDx-UM test result as a prognostic method for determining risk of metastasis and recommended differential surveillance regimens based on a Class 1A, 1B, and 2 result. DecisionDx-UM is the only prognostic test for uveal melanoma that has been validated in prospective, multi-center studies, and it has been shown to be a superior predictor of metastasis compared to other prognostic factors, such as chromosome 3 status, mutational status, AJCC stage and cell type.

It is estimated that nearly 8 in 10 patients diagnosed with uveal melanoma in the U.S. receive the DecisionDx-UM test as part of their diagnostic workup.

More information about the test and disease can be found at www.CastleTestInfo.com.

About Castle Biosciences

Castle Biosciences (Nasdaq: CSTL) is a leading diagnostics company improving health through innovative tests that guide patient care. The Company aims to transform disease management by keeping people first: patients, clinicians, employees and investors.

Castle’s current portfolio consists of tests for skin cancers, uveal melanoma, Barrett’s esophagus and mental health conditions. Additionally, the Company has active research and development programs for tests in other diseases with high clinical need, including its test in development to predict systemic therapy response in patients with moderate-to-severe psoriasis, atopic dermatitis and related conditions. To learn more, please visit www.CastleBiosciences.com and connect with us on LinkedIn, Facebook, Twitter and Instagram.

DecisionDx-Melanoma, DecisionDx-CMSeq, DecisionDx-SCC, myPath Melanoma, DecisionDx DiffDx-Melanoma, DecisionDx-UM, DecisionDx-PRAME, DecisionDx-UMSeq, TissueCypher and IDgenetix are trademarks of Castle Biosciences, Inc.

¹Decision Regret Scale: AM O’Connor, 1996

View source version on businesswire.com: https://www.businesswire.com/news/home/20220623005296/en/