Takeda’s efforts to develop an effective vaccine against Zika virus have earned it a fast-track designation from the US FDA.
The fast-track status “highlights the significance of Zika and the need for a safe and effective vaccine to protect vulnerable populations”, says Takeda whose candidate TAK-426 is in phase I testing.
Zika has emerged as a global public health threat over the last decade, with an acceleration in cases over the last five years. Most people who get infected remain symptom-free, although some develop a creeping paralysis called Guillain-Barre Syndrome (GBS) that eventually wears off. The consequences of unborn exposure are dramatic, including congenital Zika syndrome (CZS) characterised by microcephaly and other congenital brain abnormalities.
An outbreak of the virus in Brazil in 2015-16 resulted in almost 2,000 infants born with microcephaly, while the US Centers for Disease Control and Prevention (CDC) says there were more than 50 births with congenital abnormalities linked to Zika.
Brazil declared the latest epidemic over last May, after a sharp reduction in microcephaly cases that could suggest that high levels of GBS – originally thought to be attributed to Zika – were in fact caused by the chikungunya virus which is not known to cause congenital malformations.
Nevertheless, the risk of another outbreak is ever-present and efforts to develop an effective vaccine have run into obstacles, putting the target of having an effective product available by 2020 in jeopardy.
Takeda is thought to be furthest ahead in development with TAK-426 – a purified, inactivated, alum-adjuvanted, whole Zika virus vaccine candidate – after Sanofi Pasteur dropped its development programme for another whole, inactivated vaccine last year in the wake of a decision by the US federal funding body BARDA to reduce financial assistance.
BARDA opted to put its financial aid behind a single candidate and selected TAK-426 as the most likely to make it through to market.
Laurence De Moerlooze, Takeda’s global Zika programme lead, said: “As soon as Takeda received funding from BARDA, we mobilised a team and prioritised development of this vaccine candidate, initiating a phase I trial within 15 months of contract signature.
“With fast track designation, the ongoing support of BARDA, and the abilities of our organisation, we are confident that we will continue to make expedient progress.”
Takeda isn’t the only company with an active programme in this area, however. Last year Inovio Pharma and GeneOne Life Sciences reported phase I data with their synthetic GLS-5700 DNA vaccine in the New England Journal of Medicine (NEJM), concluding that it was safe and generated virus neutralising antibodies in about half of all samples tested.
Meanwhile, the National Institute of Allergy and Infectious Diseases (NIAID) in the US reported positive phase I results for a pair of DNA vaccine candidates in The Lancet last month, and is now preparing for phase II testing.