Company: CSTL
Filing Date: 2025-11-03
Form Type: 10-Q
Source: 0001628280-25-048254
Chunk: 92

Company: CASTLE BIOSCIENCES INC
Filing Date: 2025-11-03
Form: 10-Q
Item: Item 1A
Chunk 92
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 alter our marketing of LDTs and negatively impact our business, financial condition, and results of operations.

The FDA may modify its enforcement discretion policy with respect to LDTs in a risk-based manner, and we may become subject to extensive regulatory requirements and may be required to conduct additional clinical trials prior to continuing to sell our existing tests or launching any other tests we may develop, which may increase the cost of conducting, or otherwise harm, our business.

On May 6, 2024, the FDA published a final rule which amended 21 CFR Part 809 to make explicit that LDTs are IVDs and are regulated as devices under the FD&C Act. However, on March 31, 2025, the United States District Court for the Eastern District of Texas vacated the FDA’s LDT final rule. The U.S. government did not appeal the ruling, and the FDA rescinded the rule on September 19, 2025.

Despite FDA’s rescission of the LDT final rule, if the FDA implements new policy that affects LDTs or their components, and our products become subject to the FDA’s requirements for premarket review of medical devices, we may be required to cease commercial sales of our products and conduct clinical trials prior to making submissions to the FDA to obtain premarket authorization or approval. If we are required to conduct such clinical trials, delays in the commencement or completion of clinical trials could significantly increase our product development costs and delay commercialization of any currently marketed testing that we may be required to cease selling or the commercialization of any future tests that we may develop. Many of the factors that may cause or lead to a delay in the commencement or completion of clinical trials may also ultimately lead to delay or denial of marketing authorization. The commencement of clinical trials may be delayed due to insufficient patient enrollment, which is a function of many factors, including the size of the patient population, the nature of the protocol, the proximity of patients to clinical sites and the eligibility criteria for the clinical trial. Moreover, the FDA may request that we provide additional analyses and information beyond that which we intend to produce based on the designs of our current and planned validation studies or clinical trials, or that we modify or narrow our intended use or product claims. It is possible that the FDA, among other things, could disagree with our interpretation of data we have relied on to support certain intended uses. If we are required to provide additional analyses or additional data or perform additional clinical trials beyond those we currently contemplate to support the intended uses