Ipsat Therapies lead the way in bioengineered enzymes

When a patient takes an antibiotic, it doesn't just kill the pathogenic bacteria - it also changes the composition of the microflora in the gut, killing some bacteria that should be there, while allowing others such as Clostridium and Candida species that shouldn't be to flourish.

The result can be diarrhoea, severe local intestinal infections or even colitis. Further antibiotics then have to be taken to kill the unwanted species, which helps to spread resistant microbial strains.

Helsinki-based Ipsat Therapies' lead product is a bioengineered enzyme that removes the excess unabsorbed antibiotic from the intestines, maintaining a normal intestinal microflora. The idea is that it will be administered alongside the antibiotic, and the lead product is designed to work with beta-lactams.

'After the third day of a normal course of antibiotics, only 30% of the most common microflora remain,' explains Ipsat's managing director Marion Carson. 'And coliform resistance rises, with 90% being resistant on the third day, compared with just 3% when no antibiotic had been taken.'

The situation doesn't completely recover when the patient stops taking the antibiotic, so there is always selective pressure for non-resistant strains. 'It goes back to, say 70% by day 14 after treatment. It may take as much as a year to recover fully - but certain essential bacteria will also be missing.'

The product, P1A, has already undergone early stage clinical trials, and further studies are due to begin later this year.

Carson says: 'we don't know yet how many enzymes we will need to cover all antibiotics. It's akin to adding something to the antibiotic to change its profile, but it does not interfere with the antibiotic's effect anywhere else in the body - it just minimises collateral damage in the gut.'