Date: 2016-06-22
Type of information: Initiation of development program
phase:
Announcement: initiation of development program
Company: Avacta (UK)
Product: Zika virus diagnostics
Action
mechanism: The Affimer® scaffold is based on the cystatin protein fold. Affimer reagents are selected from libraries in which 12 – 36 amino acids are diversified giving a predicted total binding surface area of 650-1000 Å2. The Affimer scaffold has been engineered so that it no longer binds to proteins found in human cells, serum or plasma so that an Affimer molecule’s interactions are specifically defined by the engineered peptide loops made up of 19 naturally occurring amino acid side chain. They can distinguish between proteins that differ by only a single amino acid, can detect subtle changes in protein expression levels even in a multiplexed format, can distinguish between multiple closely related protein domains, can be generated against targets which are intractable for antibodies and can even detect whether a protein is in an active or inactive conformation. In this study, the Zika NS1 protein was identified as the best reagent available for the selection of Affimers for Zika diagnostics. NS1 is a protein that is produced by active flaviviruses from the earliest stages of infection and therefore, if it is possible to differentiate between the different NS1 proteins that are specific to each flavivirus, then an effective and specific diagnostic can be developed.
Disease: Zika virus infection
Therapeutic area: Infectious diseases
Country:
Trial details:
Latest
news: * On June 22, 2016, Avacta, the developer of Affimer® biotherapeutics and research reagents, announced it has identified three Affimer proteins capable of binding to a recombinant form of a secreted Zika virus NS1 protein (Non-Structural protein, which is diagnostic of Zika virus infection at the early, acute stage. These Affimer binders were identified and characterised within just thirteen weeks of receiving the virus target and have the potential to be developed into new rapid point-of-care diagnostic tests for Zika infection.
The three Affimer binders are highly specific to the Zika NS1 protein and can differentiate in human serum from five other closely related viruses that give similar symptoms: Dengue, Yellow Fever, West Nile, and Japanese and Tick-borne Encephalitis. Since these viruses are very similar, there is currently no validated antibody that detects Zika virus specifically, which is a limiting factor in the development of a reliable, quick diagnostic test.
Dr Alastair Smith, Chief Executive Officer, Avacta, said: “Avacta’s Affimer technology offers a distinct advantage over antibodies in infectious disease diagnostics in terms of both rapid development times and specificity. The identification of these three Affimer binders means that new diagnostic tests could be developed that have the potential to diagnose a Zika infection from its early stages, and would be suitable for low cost, rapid point-of-care diagnostics that could be deployed widely in the field or at US transport hubs for example.
