FDA Mandates Genetic Testing for Chemotherapy Drug Capecitabine

The Food and Drug Administration (FDA) has issued a new warning requiring genetic testing for patients prescribed the chemotherapy drug capecitabine (commonly known as Xeloda®), aimed at reducing the risk of severe side effects. This directive has prompted oncologists and pharmacy experts to explore advanced technologies that facilitate the integration of genetic test results into clinical practice.

New Regulations and Clinical Implications

On October 16, 2025, Aranscia, a prominent provider of precision diagnostics, responded to the FDA’s announcement, emphasizing the need for innovative solutions to streamline genetic testing workflows. The recent FDA label update for capecitabine explicitly mandates providers to assess genetic risks associated with the DPYD gene, which is crucial for metabolizing medications like capecitabine and fluorouracil.

Dr. Houda Hachad, Vice President of Clinical Operations at Aranscia, highlighted the implications of DPYD gene variants. “A concerning number of patients have difficulty metabolizing capecitabine and fluorouracil, leading to toxic accumulations that can result in severe reactions or even death,” she stated. Variants in the DPYD gene can cause deficiencies in the enzyme dihydropyrimidine dehydrogenase (DPD), affecting 3% to 8% of the general population.

The revised label for Xeloda now features a “black box warning” indicating that “serious adverse reactions or death may occur in patients with complete DPD deficiency.” It instructs healthcare providers to conduct genetic testing prior to initiating treatment, unless immediate intervention is required. This development reflects a growing trend towards personalized medicine in oncology.

Challenges in Implementation

Advocates for pre-treatment DPYD testing anticipate that the FDA may extend similar requirements to fluorouracil in the near future. Despite the availability of standalone and panel solutions for DPYD testing from various diagnostic laboratories, many healthcare providers face operational hurdles that hinder the adoption of this critical testing as standard practice.

Dr. Hachad pointed out that while some leading academic medical centers have successfully integrated technological solutions, many community oncology centers—where approximately 80 percent of cancer patients receive treatment—often lack the resources necessary to implement comprehensive testing programs. “Access to timely testing results is vital before initiating treatment,” she noted.

Aranscia’s software solutions, including YouScript®, 2bPrecise®, and Spesana, provide a streamlined approach to managing the entire testing workflow. These tools assist in identifying patients, ordering tests, and delivering actionable reports, thereby enhancing the clinical decision-making process.

“Ensuring rapid access to high-quality testing is essential,” Dr. Hachad emphasized. “Our capabilities also include integrating various genomic results into meaningful clinical insights, which is critical for managing diverse DPYD test outcomes and other significant cancer biomarkers.”

As healthcare providers adapt to these regulatory changes, the emphasis on genetic testing underscores the importance of personalized treatment approaches in oncology. Aranscia remains committed to supporting clinicians with innovative solutions that enhance patient safety and treatment efficacy.

For further details about Aranscia and their diagnostic solutions, visit www.aranscia.com.