The traditional preclinical approach that has been the industry standard for the past several decades is based upon human tumor xenograft models; tumor models that originate from highly passaged, commercially available cell lines. The activity of chemotherapeutic agents in these xenografts has demonstrated only modest correlation with clinical activity. The limited clinical relevance and predictability of these models is likely due to genetic alterations and adaptations from successive, long term in vitro and in vivo passages.

In traditional xenografts it is difficult to determine why drugs work or don’t work, and limited data is available regarding key efficacy factors at the time that the pre-clinical process is completed and human clinical trials are initiated. We believe that these issues are an important factor resulting in the low percentage of drug candidates that successfully reach the marketplace following the initiation of clinical trials (estimated at only 8%).

Champions has developed a novel preclinical platform derived from Biomerk Tumorgraft™ models; an alternative approach that utilizes the implantation of primary human tumors in immune-deficient mice within hours after the sample is taken from the patient. The Tumorgrafts are then propagated in a manner that preserves the biological properties of the human tumor. Biomerk Tumorgrafts™ are not passaged in tissue culture and thus differ from traditional xenograft models. Histologic and molecular studies have shown that Tumorgraft models: (a) maintain the fundamental genotypic features of the original cancer, (b) represent the genetic heterogeneity of the cancer, and (c) do not change through several passages.

As a result, Biomerk Tumorgrafts™ more accurately predict the effectiveness of chemotherapeutic drugs in patients.

Reference: Rubio-Viqueira B, Jimeno A, Cusatis G, et al. An in vivo platform for translational drug development in pancreatic cancer. Clin Cancer Res 2006; 12 (15) 4652-61.