Affimers are essentially small, engineered proteins capable of binding specific molecular targets, in a similar way to antibodies.
This binding property can be used to target cancer cells in the human body and make those cells vulnerable to attack from the body’s own immune system.
Many existing immuno-oncology therapies use an antibody to target cancer, but Affimers have several innovative features which potentially make them a better tool for therapeutic applications.
They are smaller, quicker to manufacture and easier to format, but they maintain antibody-like biologic activity when binding a target.
Last week Avacta said it had has selected the cancer drug candidate that it will take into first-in-human clinical trials.
Affimer molecule AVA004 was picked because of its “excellent” properties in lab test. It will be developed as a PD-L1, one of a breed of cancer drugs known as checkpoint inhibitors.
AVA004 was shown to be as good as three of the current PD-L1 drugs already on the market in lab tests.
On the tie-up with Selexis, Avacta chief executive Alastair Smith said the company's new partner provided “the technology and know-how” to develop the required cell line for the planned first-in-human study.
“These cell lines are the essential basis of clinical manufacturing of AVA004 and this partnership supports Avacta's strategy to demonstrate safety and tolerability of the Affimer platform in humans with a planned investigational new drug/clinical trial by the end of 2020,” Smith added.