River blindness vaccine to begin trials

A vaccine with the potential to prevent millions of cases of blindness is one step closer to commercialisation, with trials in cattle set to commence before the end of the year.

River blindness, also known as onchocerciasis, affects about 17 million people globally. It is spread by blackflies that breed in rivers, infecting humans and cattle with parasitic worms known as Onchocerca volvulus. These worms produce microfilariae that migrate to the skin, eyes and other organs, causing eye inflammation, bleeding and other complications that ultimately lead to blindness.

Potential solutions to river blindness, such as ivermectin, have been developed but have often led to a resistance to the drugs. Now, a new vaccine has been created using adjuvant technology Advax from South Australian biotech company Vaxine, which developed the vaccine in association with Thomas Jefferson University and the New York Blood Center in the United States.

The scientific director of Vaxine, Nikolai Petrovsky, said one of the main problems with current river blindness prevention is the use of aluminium-based adjuvants, which are not always effective. “We offer a new alternative that is … potentially safer because it is a sugar instead of a metal/salt with high toxicity,” he said.

With the help of this sugar-based adjuvant, Advax makes the pathogen in the vaccine more easily recognised by the body’s immune system so it can develop appropriate antibodies. Petrovsky said, “Our technology is a bit like melding a turbocharger to the engine and in this case makes the vaccine dramatically more powerful.

“Our adjuvant also works for a lot of vaccines that wouldn’t work with aluminium. The ones that tried to create an onchocerciasis vaccine didn’t take, but ours actually works.”

Following a successful trial in mice, published in the journal National Center for Biotechnology Information, Petrovsky said Vaxine is now planning a two-pronged approach to effectively preventing the disease.

“First we’re looking to vaccinate the cattle, which are a breeding ground for the parasite,” he explained.

“Then the other side of this is to immunise the children, so if they come in contact with the parasite it blocks the infection.”

The group has already received a grant from the US Government for the cattle trial and plans to begin tests in the coming weeks.

This is a modified version of a news item published by The Lead South Australia under Creative Commons.