European biotech company Valneva is on the road to a Zika vaccine that’s safe for pregnant women

There is no recipe for the perfect vaccine. Despite the ever-increasing sophistication of vaccine technology, development often comes down to what researchers call “suck it and see.” Still Valneva’s vaccine could potentially be used in public health emergencies in as little as two years. That could save the lives of hundreds of babies.

Until recently Zika affected relatively few people. The estimated cost of a vaccine for the disease is EUR149-468 million. So a Zika vaccine was not on the radar. Other severe and potentially fatal mosquito-borne diseases such as malaria, dengue, and West Nile virus affect millions of people each year, making a vaccine for them a higher priority. That all changed with the explosive spread of Zika in the Americas and the potential link with microcephaly (reduced head size and brain damage) in the babies of women infected while pregnant.

Now a vaccine is a high priority. A big challenge is to ensure that a vaccine—which typically might include an agent similar to the harmful disease it’s intended to cure—doesn’t itself harm foetuses. Valneva’s response is to make a vaccine that’s a Purified Inactivated Vaccine (PIV). “Inactivated vaccines” use a disease-causing agent such as a virus or bacteria that has been killed by chemicals, heat, or radiation, for example. They stimulate the immune system to protect against the actual disease, which researchers call a “live wild-type infection”. That means that, even if the disease-causing agent in the vaccine crosses the placenta, it does not infect the foetus because it has been “inactivated.”

More quickly on the market

Valneva, which is headquartered in Lyon, develops vaccines for travellers or focuses on neglected diseases prevalent in developed countries. It started work on the Zika virus by using a similar process to one of its other vaccines—for Japanese encephalitis, originally licensed from the Walter Reed Army Institute of Research, the largest biomedical research facility administered by the US Department of Defense. US and European regulatory agencies already licenced the Japanese encephalitis vaccine, so Valneva believes this will make regulatory approval quicker for the Zika vaccine. So far the company’s Zika vaccine “demonstrated excellent purity and overall had a biological, chemical and physical profile comparable to our commercially produced Japanese encephalitis vaccine” said Franck Grimaud, Valneva’s deputy chief executive.

Lyme vaccine on the way

Valneva is also making progress on vaccines against:

• clostridium difficile, an  infectious diarrhoea commonly affecting patients in hospitals or long-term care facilities
• Lyme Borreliosis, a serious illness transmitted by infected ticks

Valneva’s Lyme vaccine addresses OspA, a protein in the bacteria that infects ticks. Currently, there is no licensed vaccine available to protect humans against Lyme disease. According to the Center for Disease Control and Prevention, 300,000 cases of Lyme disease are reported each year in the US alone, making it the most commonly reported tick-borne illness. In Europe, as many as 200,000 cases are diagnosed each year.  Valneva recently received approvals from the Food & Drug Administration and the Belgian health authority to initiate the Phase I clinical study of its Lyme vaccine candidate in the US and EU.

A proven track record

Valneva spends approximately 20% of its expected 2016 revenues on research and development. A quarter of its 400 employees work in R&D. It files about 25 patents per year.

That approach so far developed two vaccines for travellers:

• Ixiario, for Japanese Encephalitis, a viral neurological disease that kills approximately 20 000 people each year
• Dukoral, which protects against enterotoxigenic escherichia coli (Etec) and cholera (which kills up to 120 000 each year)

Both Valneva vaccines prevent diseases for which there are no other approved products in Europe. In the case of Japanese encephalitis, there’s also no product in the US.

EU finance for innovators

Valneva got a EUR 25 million loan from the European Investment Bank in June 2016. The EIB financing will support the research and development of vaccines including for Lyme and Zika. “This is an innovative financing operation, which will have a real impact on the health and daily life of Europe's citizens,” says EIB Vice-president Ambroise Fayolle. “Valneva is an excellent example of a truly European company. It was created by a European cross-border merger and has operations in France, Austria, Sweden and the United Kingdom,” commented EIB Vice-President Ambroise Fayolle ahead of the contract signing ceremony.