Company: RCUS
Filing Date: 2025-05-06
Form Type: 10-Q
Source: 0001724521-25-000063
Chunk: 74

Company: Arcus Biosciences, Inc.
Filing Date: 2025-05-06
Form: 10-Q
Item: Part I, Item 4
Chunk 74
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 intended population. To satisfy these requirements, the FDA may recommend we conduct a clinical factorial study, designed to assess the effects attributable to each drug in the combination product. Moreover, the applicable requirements for approval of a combination therapy may differ from country to country.

In the event that one of our investigational products were to fail to demonstrate sufficient safety and efficacy or establish its contribution to the claimed effects of a combination therapies, we would need to identify alternatives. For example, we expect that our anti-PD-1 antibody, zimberelimab, will form the backbone of many of the investigational combination therapies we are pursuing. If we are unable to demonstrate the contribution of zimberelimab to the claimed effects of an investigational combination therapy, we would need to identify an anti-PD-1 antibody for use in such combination therapy. In the event we are unable to do so or are unable to do so on commercially reasonable terms, our business and prospects would be materially harmed.

Certain of our investigational products may require companion diagnostics in certain indications. Failure to successfully develop, validate and obtain regulatory clearance or approval for such tests could harm our product development strategy or prevent us from realizing the full commercial potential of our investigational products. 

Companion diagnostics are subject to regulation by the FDA and comparable foreign regulatory authorities as a medical device and may require separate regulatory authorization prior to commercialization of either the companion diagnostic or the relevant investigational product. According to FDA guidance, if the FDA determines that a companion diagnostic device is essential to the safe and effective use of a novel therapeutic product or indication, the FDA generally will not approve the therapeutic product or new therapeutic product indication if the companion diagnostic is not also approved or cleared for that indication. Depending on the data from our clinical trials, we may utilize diagnostic tests, during our clinical trial enrollment process to help identify patients with characteristics that we believe will be most likely to respond to our investigational products. For example, certain clinical trials that we are conducting, such as our STAR-221 trial, use a diagnostic test to measure PD-L1 levels in tumor samples provided by enrolled patients. Our future trials may also use a diagnostic test to help identify eligible patients. In addition, we have significant efforts directed to identifying changes in various cells and proteins to understand their relationship, if any, to the clinical activity observed in our clinical trials and to assess if such cells and/or proteins could be used as predictive biomarkers to select for patients more likely to respond to our investigational products. However, we cannot be certain