Takeda says it has started a phase IIb clinical trial of a candidate vaccine against norovirus, which kills an estimated 200,000 people worldwide every year.
Norovirus – sometimes known as the ‘winter vomiting bug’ causes 700m cases of acute gastroenteritis (AGE) every year with symptoms including diarrhoea and vomiting, abdominal cramps and fever. It accounts for around 20% of all diarrhoeal cases worldwide, with most deaths occurring in low-income countries.
While most infections clear up within a few days, in some cases they can cause significant dehydration that can be life-threatening. There is no drug treatment available, so management of norovirus focuses on preventing transmission and supportive care for those infected.
Norovirus is massively contagious and tends to be acquired from contact with contaminated food or surfaces or from an infected person, so a vaccine would be a major boost to efforts to control the disease.
Takeda said the first patient has now received its TAK-214 vaccine in the phase IIb trial, which is due to enrol 3,400 patients and complete in August 2017. The vaccine will be compared to placebo in healthy volunteers – recruited from US military training installations – to see if it can prevent AGE.
“This trial moves us one step closer to putting an important tool for prevention in the hands of individuals, families and public health systems around the globe,” commented Robert Goodwin, who heads the norovirus development programme at Takeda.
TAK-214 is based on a virus-like particle platform (VLP) technology, which enables the production of vaccines that can target multiple genetic varieties of viruses. It includes antigens from norovirus genotypes GI.1 and GII.4, which are thought to cause the majority of human illness.
According to estimates compiled by the US Centers for Disease Control and Prevention (CDC) and the Bill and Melinda Gates Foundation, the global economic burden of norovirus is an eye-watering $60bn per year.
Takeda acquired rights to TAK-214 when it bought US biopharma company LigoCyte in 2012 in a $60m deal and says it remains the only norovirus vaccine candidate in clinical development.
Market observers have suggested that – if approved – the vaccine could meet or even exceed sales of GSK’s Rotarix vaccine for rotavirus-related diarrhoea, which was launched in 2011 and grew 14% last year to reach £417m ($615m).