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The persistence, biodistribution, and risk of integration into the host genome of any new therapeutic DNA vaccine must be established in preclinical studies. We previously developed the DNA vaccine pcDNA-CCOL2A1 encoding chicken type II collagen (CCII) for the treatment of rheumatoid arthritis (RA). In the present study, we characterized its dynamic profile, biodistribution, and potential for genomic DNA integration in normal vaccinated rats. A real-time quantitative PCR analysis of animals administered a single dose of pcDNA-CCOL2A1 (300 µg/kg by intramuscular injection) showed that CCOL2A1 mRNA level in the blood peaked between 2-6 h post-immunization and then rapidly declined, and was undetectable between day 1 and 42. CCOL2A1 transcript was detected at the muscle injection site at 3-14 days post-immunization. Starting from day 14, the transcript was detected in the heart, liver, lungs, and kidney but not in the spleen or thymus, and was expressed only in the lungs on day 28. There was no CCOL2A1 mRNA present in the testes or ovaries at any time point. Non-invasive in vivo fluorescence imaging revealed CCII protein expression from 2 h up to 10 days and from 2 h up to 35 days after administration of pcDNA-CCOL2A1 via the intravenous and intramuscular routes, respectively; the protein had disappeared by day 42. Importantly, CCOL2A1 was not integrated into the host genome. These results indicate that the pcDNA-CCOL2A1 vaccine is rapidly cleared within a short period of time and is therefore safe, and merits further development as a therapeutic vaccine for RA treatment. Funding Statement: This study was supported in part by a grant from the National Major Scientific and Technological Special Project for “Significant New Drug Development” (No.2009ZX09103-624 and No.2015GKS-072/139 to Xi YZ). The funding agency played no role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript. Declaration of Interests: The authors have no conflicts of interest to declare in this work. The authors alone are responsiblefor the content and writing of the paper. Ethics Approval Statement: All work including animal studies were conducted following the guidelines of the Academy of Military Medical Sciences Animal Welfare Committee.