| abstract |
A drug delivery composition, comprising a bioelastic polymer, comprising monomeric units selected from the group consisting of bioelastic pentapeptides, tetrapeptides, and nonapeptides, and a drug retained by the polymer, wherein the polymer is selected to be in a first contraction state, selected from the group consisting of contracted and relaxed bioelastomer states, when contacted with a physiological condition present in a human or animal to whom the composition is administered and wherein the polymer contains a reactive functional group that undergoes a reaction, either in the presence of the physiological condition or when the polymer is transported by a natural process in the human or animal to a different location having a different physiological condition, to produce a second functional group, wherein the presence of the second functional group in the polymer causes the polymer to switch to the other of the contraction states, thereby making the drug available for release from the composition. |