Integrating Drug-Drug Interactions and Lifestyle Factors with Drug-Gene Interactions Provided by Castle Biosciences’ IDgenetix® Test Significantly Impacted the Number of Drug Recommendations for Patients with Moderate to Severe Depression

IDgenetix is a clinically validated pharmacogenomic (PGx) test that incorporates the results of drug-gene interactions with drug-drug interactions and lifestyle factors, such as smoking and use of over-the-counter medicines and dietary supplements, to provide medication recommendations for patients with mental health conditions

Castle Biosciences, Inc. (Nasdaq: CSTL), a company improving health through innovative tests that guide patient care, today announced data from a study showing the addition of drug-drug interactions and lifestyle factors to drug-gene interactions provided by its IDgenetix® test significantly impacted the number of drug recommendations and contributed to improved remission rates for patients with moderate to severe depression. The data was shared at Psych Congress 2023 in a poster titled, “The Importance of Incorporating Drug-Drug Interactions and Lifestyle Factors in Pharmacogenomics-Guided Medication Management for Patients with Major Depressive Disorder in a Randomized Controlled Trial.”

“There are many factors that can impact how a patient responds to and metabolizes mental health medication, such as their genetics, other drugs being taken and lifestyle choices like smoking,” said Robert Cook, Ph.D., senior vice president of research and development at Castle Biosciences. “This study reinforces the value of our IDgenetix test in providing personalized information for each patient, taking drug-gene, drug-drug and lifestyle factor interactions into account, to guide optimal medication selection that may help patients with depression achieve faster remission from their symptoms.”

IDgenetix is supported by a published randomized controlled trial (RCT) showing that patients whose medication management was guided by the test were 2.65 times more likely to achieve remission of depressive symptoms compared to patients whose medication management was guided by the standard-of-care, trial-and-error approach.¹ The study shared at Psych Congress 2023 evaluated the contribution of drug-gene, drug-drug and lifestyle factors to IDgenetix-guided medication management in patients with moderate to severe depression from this RCT (n=261).

The non-genetic information (drug-drug interactions and lifestyle factors) accounted for 43% of all drug recommendations in study participants, while single-gene testing for CYP2D6 and CYP2C19 contributed to only 22%. At 12 weeks, patients whose medication management was guided by IDgenetix had a remission rate of 41%, compared to only 27% of patients whose medication management was not guided by the test (p=0.03, risk ratio=1.49 [1.05-2.12]). Among a subset of the patients taking actionable antidepressants at baseline (n=106), remission rates were even more significantly improved for the IDgenetix-guided group compared to the unguided group (47% vs. 22%, p=0.01, risk ratio=2.15 [1.16-3.96]).

The poster can be viewed here and will also be published on HMP Global’s Psychiatry & Behavioral Health Learning Network in approximately 30-60 days.

About IDgenetix®

IDgenetix® is an advanced pharmacogenomic (PGx) test designed to guide medication selection and management for patients with neuropsychiatric conditions, such as depression and anxiety. IDgenetix provides important genetic information to clinicians to help guide personalized treatment plans for their patients, with a goal of helping patients achieve faster therapeutic response and improving their chances of remission by identifying appropriate medications more efficiently than the standard-of-care, trial-and-error approach. IDgenetix integrates drug-gene, drug-drug and lifestyle factor interactions in a clinically actionable report and is supported by a published, peer-reviewed randomized controlled trial that demonstrated clinical utility over the standard of care when physicians reviewed IDgenetix results prior to prescribing a medication. More information can be found at www.IDgenetix.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, X and Instagram.

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

Forward-Looking Statements

This press release contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended, which are subject to the “safe harbor” created by those sections. These forward-looking statements include, but are not limited to, statements concerning: the potential of IDgenetix to provide personalized information for each patient to guide optimal medication selection that may help patients with depression achieve faster remission from their symptoms. The words “can,” “may,” “potential,” “will” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. We may not actually achieve the plans, intentions or expectations disclosed in our forward-looking statements, and you should not place undue reliance on our forward-looking statements. Actual results or events could differ materially from the plans, intentions and expectations disclosed in the forward-looking statements that we make. These forward-looking statements involve risks and uncertainties that could cause our actual results to differ materially from those in the forward-looking statements, including, without limitation: subsequent study or trial results and findings may contradict earlier study or trial results and findings or may not support the results shown in this study, including with respect to the discussion of IDgenetix in this press release; actual application of our tests may not provide the aforementioned benefits to patients; and the risks set forth under the heading “Risk Factors” in our Annual Report on Form 10-K for the year ended December 31, 2022 and in our other filings with the SEC. The forward-looking statements are applicable only as of the date on which they are made, and we do not assume any obligation to update any forward-looking statements, except as may be required by law.

1. Bradley P, Shiekh M, Mehra V, et al. Improved efficacy with targeted pharmacogenetic-guided treatment of patients with depression and anxiety: A randomized clinical trial demonstrating clinical utility. J Psychiatr Res. 2018 Jan;96:100-107. doi: 10.1016/j.jpsychires.2017.09.024. Epub 2017 Sep 23. PMID: 28992526.

View source version on businesswire.com: https://www.businesswire.com/news/home/20230909285042/en/