September 1, 2009 (Vol. 29, No. 15)
In all areas of clinical testing, peptide-based therapeutics have dramatically increased, nearly doubling from 2000 to 2007,” says Ralf Brandt, Ph.D., CEO and managing director of vivoPharm. “However, many have failed due to lack of sufficient efficacy.”
Some of the failures may be due to the fact that there are not enough clinically relevant models for testing the efficacy of biologics. This is especially the case with cancer models where, according to Dr. Brandt, more than 90% of the time the traditional subcutaneous tumor model, “which is characterized by low vascularization resulting in the development of necrotic areas and a low rate of drug delivery, is used. The testing of biologics needs a new, more modern testing approach focusing on more clinically relevant models,” he noted.
Tissue models with good vascularization (e.g., orthotopic tumor models), should be the first choice when it comes to testing biologics, Dr. Brandt said. vivoPharm utilizes many tumor models for testing new biologics produced by its pharma customers. “It has been clearly shown in our hands that if the model and/or protocol are chosen wisely and optimized for the peptide to be tested, the outcome of preclinical studies can be encouraging.”