Two drugs impress in calf cryptosporidiosis trial
© Mike Greenslade/Alamy Stock Photo Early research evaluating two unnamed drug molecules for controlling cryptosporidiosis in calves has yielded positive results, taking them to the next developmental stage.
Calves infected with cryptosporidium got better when given one or two organic compounds – DDD489 and DDD508 – in a university trial.
The drug molecules work by inhibiting the effect of a specific enzyme (lysyl-tRNA synthetase) that is essential for cryptosporidium survival.
See also: How to tackle cryptosporidium in calves
Both drugs were administered orally with feed in a liquid suspension.
The research follows studies on mice carried out to demonstrate the compounds’ efficacy at killing cryptosporidium.
Dr Nicola Caldwell, team leader at Dundee University’s drug discovery unit, said the studies were “very encouraging” and would help develop treatments for human and veterinary applications.
“Mice don’t naturally get cryptosporidium infection and don’t display symptoms such as diarrhoea, so the calf studies are much more relevant for studying cryptosporidiosis.”
Study outline
The drugs were developed by staff at the Universities of Dundee and Vermont in collaboration with Moredun Scientific.
Researchers treated half a group of neonatal calves and gave a placebo to the other half.
Treated group Given either compound twice a day for seven days:
- Showed no detectable parasite shedding during treatment and seven days post-treatment
- Produced normal faeces or mild scour.
Control group Given a placebo in place of treatment:
- Showed high levels of parasite shedding
- Shedding peaked one week after infection.
Further research
Larger field trials will be needed before the compound can be licensed for use and made available for farmers and veterinarians, researchers said. At this point, the drugs would be given names.