Oral E coli vaccine moving into phase II trials
Protection against travellers' diarrhoea has moved a step closer.
An oral vaccine against enterotoxigenic Escherichia coli (ETEC) disease,
the commonest cause of travellers’ diarrhoea, is moving into phase
II studies after a successful volunteer trial.
The manufacturer, biotechnology company Microscience, says that the phase
I trial demonstrated the safety and immunogenicity of its product. The
open label study, involving 36 volunteers, showed that, after a single
dose, 50 per cent had high levels of immune
response. After two doses the response rate rose to 70 per cent.
The live vaccine is made from salmonella bacteria, rendered harmless
by removal of key genes involved in the infection process. The bacteria
are also modified to carry an ETEC antigen. This technology is described
as spi-VEC. The company explains that the bacteria then deliver the antigen
directly to cells of the immune system.
Clinical investigator David Lewis said: “The results of this first
study with spi-VEC are exciting and these are the best results achieved
to date in humans using this type of oral delivery system.” Phase
II trials will aim to demonstrate protection against ETEC disease and
develop a dosing regimen to ensure recipients gain immunity rapidly. |
The
Pharmaceutical Journal