Rebus Holdings, Inc. is a pharmaceutical company. The Company is focused on the research and development of targeted precision therapeutics for the treatment of cancer. The Company utilizes its proprietary delivery technology to enhance immuno-modulation for developing therapeutic outcomes. Its immune-oncology lead asset, RT-AR001, is an adenosine A2A receptor antagonist, differentiated by its intratumoral delivery of nano- or microparticle formulations that allow for better tumor infiltration. Its patented portfolio of adenosine receptor antagonists provides treatment based on the specific adenosine targets found in each type of cancer. The adenosine receptor modulators include A2A, A2B and dual A2A/A2B antagonists, that have broad development applicability, including indications within immuno-oncology. The Company is also engaged in the manufacturing of platform delivery systems for nano- or microparticle formulations that are used in toxicology studies.