An unbalanced microbiome is due to a lack of diversity of different bacteria species/strains on the skin.
This lack of diversity is common to acne-prone skin and eczema-prone skin.
By restoring the diversity of the bacteria on the skin, the microbiome is healthier, correlating to healthier skin overall. This microbiome acts as a natural healer and protector by forming an invisible shield against external aggressors.


Microbiome science has been at the core of our research in recent years. As a result, we developed a new active ingredient called Aqua Posae, a delicate strain that grows in our thermal water. Once introduced in our formulas the results were beyond our expectations: The microbiome was rebalanced.

At La Roche-Posay we have always pushed the boundaries of what is possible in skincare.
For nearly the past 10 years we have focused our energy on this new field of research, Microbiome Science.
It has really changed our approach to skincare.
Traditionally skincare was designed to correct the visible signs of skin conditions.
But what we have learned through our studies on the microbiome is that there is this invisible ecosystem of bacteria living on your skin.
And the balance between these different species play a vital function to your health.

We could see a direct correlation:
If your microbiome ecosystem was balanced your skin was healthier.
If unbalanced, problems would appears stronger.
So we thought, what if we could find a way to rebalance this microbiome, to find a better outcome.
Working with our laboratories on Microbiome Science to develop a new type of ingredient.

A delicate strain grown on our thermal water. 
A powerful prebiotic. We call it Aqua Posae.
“You see here the original strain, stored at -80c. Grown on thermal water, and it is contently monitored for 24/7. We then condition it so that it can be placed in our product at the right concentration. This process is patented and totally unique.”

Once in our product the results were beyond our expectation:
The microbiome was rebalancing, and staying balanced.
Signs of skin conditions dramatically decreased, and skin stayed healthy.
At La Roche-Posay our mission is to provide life changing dermatology  for those with sensitive skin.

We believe our Microbiome Science is the change the industry needs and we are excited to lead it that change.


We have cultivated a new ingredient.

A unique bacteria strain called Viitreoscilla filiformis is cultivated in thermal spring water.

An unique living ingredient.

Scientists has deepen their researches and they found out that this bacteria strain has unique healing and protective properties.

The process that makes it so unique
The Viitreoscilla filiformis is cultivated and grown slowly in LRP thermal spring water and gently with 24/7 care through a process called Fermogenese.

Back of card A constant care made by experts
The Biochemists track the growth by checking all the parameters making precise daily diagnosis to adjust the care to make sure it grows properly.

This strain is gently defrosted and brought back to life.
The strain is incredibly fragile and must be slowly stirred in exactly the right conditions or risk of dying or losing its unique properties. 

The culture conditions are highly controlled and stabilized during all the process;
This precious strain is really sensitive , a variation of 1 or 2 degrees can have an impact on its growth. 

It is fed oxygen, and thermal spring water while being kept at the right pressure and pH level.
To help the strain multiply and in order to give it its unique properties.

Collect of the strain at its highest level to get the best performances
When the growth rate is at it’s highest level, the laboratories collect the strain to get its best performances. 

After multiplying 1000X in population this strain is ready to be added into our products
This process is fully automated to avoid external contaminations from the environment.

This powerful prebiotic is called, at this stage of the process, Aqua Posae Filiformis and it is added in our product
This ingredient helps rebalancing your skin microbiome that is needed for patients. 

Aqua posae filiformis is made in France, coming through green science process, without added solvant and using only renewable ingredients. 
This process respects the environment by minimizing water and energy consumption. 

This ingredient enrich our formula This ingredient enriched our formulain one of the first eco-friendly factory in France.
Carbon neutral, 100% renewable energy, 100% wasterwater recycled, smart construction & green spaces. 


Discover products that contain Aqua Posae Filiformis.


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