Avimers have been developed by the biotechnology company Avidia, now part of Amgen, as potential new pharmaceutical drugs.
The individual sequences are derived from A domains of various membrane receptors and have a rigid structure, stabilised by disulfide bonds and calcium.
In a study, the plasma half-life of an anti-interleukin 6 avimer could be increased by extending it with an anti-immunoglobulin G domain.
[1] They have improved heat stability compared with antibodies, but limited plasma half-life because of their smaller size.
The most promising species are linked to a second A domain via a short linker peptide, forming a new library.