Company: RCUS
Filing Date: 2025-02-18
Form Type: 424B5
Source: 0001193125-25-028669
Chunk: 6

Company: Arcus Biosciences, Inc.
Filing Date: 2025-02-18
Form: 424B5
Chunk 6
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 our product development programs. |

| • |     | If we are unable to obtain regulatory approval for our investigational products, or experience significant delays 
 in doing so, our business will be materially harmed.                                                              |

| • |     | Preliminary and interim data from our clinical studies that we announce or publish from time to time are subject                                   
 to audit and verification procedures that could result in material changes in the final data and may change as more patient data become available. |

| • |     | Enrollment and retention of subjects in clinical trials is expensive and time consuming and can be made more                                                                                                                                        
 difficult or rendered impossible by competing treatments, clinical trials of competing investigational products, geopolitical instability and public health epidemics, each of which could result in significant delays and additional costs in our 
 product development activities, or in the failure of such activities.                                                                                                                                                                               |

| • |     | Serious adverse events, undesirable side effects or other unexpected properties of our investigational products                                                                        
 may be identified during development or after approval, which could lead to the discontinuation of our clinical development programs, refusal by regulatory authorities to approve our |

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| investigational products or limitations on the use of our investigational products or, if discovered following marketing approval, revocation of marketing authorizations or subsequent limitations 
 on the use of our investigational products.                                                                                                                                                         |

| • |     | A key element of our strategy is the development of intra-portfolio combinations. If we are not successful in                                                                                                                                           
 discovering, developing and commercializing investigational products that take advantage of different mechanisms of action to achieve superior outcomes relative to the use of single agents or other combination therapies, our ability to achieve our 
 strategic objectives would be impaired.                                                                                                                                                                                                                 |

| • |     | 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. |

| • |     | We expect to depend on our collaboration with Gilead for the research, development, manufacture and                                   
 commercialization of our investigational products. If this collaboration is not successful, our business could be adversely affected. |

| • |     | We rely on third parties to conduct our clinical trials and perform some of our research and preclinical studies.                                                                                                                                       
 If these third parties do not satisfactorily carry out their contractual duties or fail to meet expected deadlines, our development