(BFM Stock Exchange) – The title of the company specializing in infectious disease vaccines suffers on the Paris Stock Exchange on Monday, April 28 after the Chikungunya vaccination campaign was suspended for the elderly. This after three cases presented serious side effects.

If the equity markets have had confusing volatility since the beginning of the year, Valneva holds the road well, displaying an increase of 36.5% over the period.

The action was supported by a flow of positive announcements, such as a new American army order for Ixiaro, the Valneva vaccine against Japanese encephalitis, or marketing authorizations in different countries for IXCHIQ, the company’s vaccine against chikungunya.

More recently, the company specializing in infectious diseases has announced the supply of 40,000 doses of this same IXCHIQ vaccine to combat the chikungunya epidemic on Reunion Island.

Following a recommendation from the High Authority for Health (HAS), these doses must first allow people to be vaccinated over 65 and suffering from comorbidity. That is to say, patients who, in addition to a first disease (here chikungunya) have a second likely to worsen the prognosis or modify the treatment.

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Vaccination suspension for 65 years and over

Since the beginning of the year, 40,000 cases of chikungunya have been identified on Reunion Island, which has raised fears of a risk of transmission to the metropolis as well as to other French overseas territories.

However, the vaccination campaign in which Valneva intervenes was interrupted at the end of last week, for people aged 65 years and more. “Vaccination remains open for people aged 18 to 64 with comorbidities,” the Ministry of Health said in a statement.

This decision was made on April 25, after three people on the island presented serious unwanted events after vaccination. These three people were over 80, with comorbidities.

“Those people have presented symptoms similar to those of a serious form of chikungunya a few days after vaccination, one of which died. The third came out of hospitalization,” said the Ministry of Health.

In a statement published on Monday, Valneva relayed the information previously communicated by the Ministry of Health and said “Labor (ER) actively in concert with the regulatory authorities on the next steps”.

“Valneva undertakes to comply with the strictest security standards and is suitable for the importance of pursuing the rigorous surveillance protocols which are in place. We appreciate the precautionary measures taken by the authorities while the exams are underway and in the context of the active vaccination campaign,” said Juan Carlos Jaramillo, the medical director of Valneva, quoted in the press release.

“We continue to encourage healthcare professionals to assess the benefit/risk of vaccination according to the medical history of each person, while we are working on a potential update of the indication of the product,” he added.

On the Paris Stock Exchange, this announcement was very badly welcomed, before the market put it into perspective. The action unscrewed by 20% after being briefly suspended at the start of the session. Around 11:20 am, the title lost only 7.7%.

“For the time being, the suspension of vaccination remains preventive, it is not a question of stopping the marketing of the vaccine. In addition, the side effects were observed on very elderly people who presented comorbidities,” notes Mohamed Kaabouni, analyst at Portzamparc.

“In the immediate future, there is no matter to be alarmed, even if it will be necessary to see what the investigation will say as to the causality between vaccination and undesirable effects. We must therefore wait and see,” he concludes.

“In the medium term (4-5 years), and according to our estimates, Ixchiq could generate a peak of annual sales around 200 million euros,” said the analyst.