The present invention is directed to methods for developing one or more drugs for one or more targeted therapies and compositions derived therefrom. In accordance with one aspect of the present invention, combinatorial chemistry techniques for use with high throughput screening techniques for identifying small molecule affinity and/or activity interactions are avoided by instead utilizing the natural mechanisms of antigen response to effect a massively parallel screening of naturally occurring molecules against an antigen. Other aspects of the invention provide compositions derived therefrom as well as therapeutic methods of use for the compounds.