ADU-741 (JNJ-64041809) is an investigational bacteria-based cancer vaccine being developed by Aduro Biotech in partnership with Janssen Biotech for the treatment of metastatic castration-resistant prostate cancer (mCRPC). mCRPC is a cancer of the prostate that has spread to other parts of the body and that keeps growing even when treatments are used to lower the amount of male sex hormones to manage the cancer.

In December 2015, Aduro Biotech received a milestone payment from Janssen Biotech for the acceptance of an investigational new drug (IND) application by the U.S. Food and Drug Administration (FDA) for ADU-741.

How ADU-741 works

ADU-741 is designed on the basis of Aduro’s Live, Attenuated Double-Deleted Listeria (LADD) platform. It contains live, but weakened, bacteria called Listeria monocytogenes. These bacteria cannot cause disease because two essential disease-causing genes have been deleted. The deletion of these virulence genes prevents the bacteria from infecting liver cells and spreading. This enables the vaccine to induce an immune response without causing harm. This type of vaccine is called a live attenuated vaccine.

The attenuated bacteria are then engineered to express molecules, or antigens, that are specifically present on prostate cancer cells. When administered as an injection into the bloodstream, these bacteria that express prostate-specific antigens induce a strong immune response against prostate cancer cells, thereby killing them.

ADU-741 in clinical trials   

An open-label, two-part Phase 1 clinical trial (NCT02625857) was started in 2015. The aim of the study is to evaluate the safety and immunogenicity — the ability to trigger an immune response — of ADU-741 in patients with mCRPC.

The first part of the study is a dose escalation to determine the ideal dose to be used in the second part, based on safety and pharmacodynamic (the way the drug affects the body) assessments. Once the recommended dose is determined, part 2 will further evaluate the safety and preliminary immunological and clinical activity of the treatment.

The study consists of a screening period, an open-label treatment period, and a post-treatment follow-up period. It is currently ongoing at different sites in the U.S but not recruiting participants. It is expected to be completed by January 2018.


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