Dry eye disease is widely understood as a lack of moisture. But the science tells a more complex story.

According to the latest TFOS DEWS III consensus report, dry eye disease is driven by a self-reinforcing cycle: tear film instability leads to hyperosmolarity, hyperosmolarity contributes to inflammation, inflammation causes ocular surface damage, and the cycle begins again.

Most formulations target only one part of this cycle.

Conventional lubricants such as hyaluronic acid, carboxymethylcellulose, and lipid emulsions help replenish, lubricate, and stabilise the tear film at the surface. They do this well. But they do not fully address what is happening underneath: the osmotic stress that can continue to affect ocular surface cells, even when the surface appears supported.

This is where osmoprotection comes in.

The dry eye cycle, explained

The TFOS DEWS III report describes four interconnected processes that drive dry eye disease.

First, tear film instability causes the tear film to break up more quickly. This increases evaporation and triggers the cycle.

Next, hyperosmolarity develops. The tear film becomes too concentrated, exposing ocular surface cells to osmotic stress.

Under this stress, epithelial cells become more vulnerable to damage. Goblet cell function can also be affected, which may further compromise tear film quality.

Cell stress then contributes to inflammatory signalling. This further disturbs tear film balance and keeps the cycle going.

The critical insight is that each stage feeds into the next. Treating the surface alone may not be enough to interrupt this loop.

What is osmoprotection?

An osmoprotectant does not replace the tear film. Instead, it works at the cellular level.

Osmoprotection helps protect ocular surface cells from the hyperosmolar stress that conventional lubricants do not directly address. By acting earlier in the dry eye cycle, it supports cellular resilience and may help reduce downstream inflammatory stress signals.

It is not an alternative to lubrication. It is a complementary formulation approach that addresses a different, and often overlooked, mechanism in dry eye disease.

How Ectoine acts

Ectoine, the active molecule in medEctoin®, targets osmotic stress at multiple points in the dry eye cycle.

Under hyperosmolar conditions, Ectoine helps stabilise proteins and cell membranes. This supports the structural integrity of ocular surface cells and helps protect them from osmotic stress.

By supporting cellular resilience at an early stage, Ectoine may also help reduce downstream inflammatory signalling, one of the processes that keeps the dry eye cycle active.

In other words, Ectoine does not wait for damage to occur. It acts where osmotic stress begins to build.

What the clinical evidence shows

medEctoin® has been evaluated in clinical studies.

In a 28-day study with patients with mild to moderate dry eye disease, an overall symptom score reduction of 46% was observed. Reported symptoms included redness, burning, foreign body sensation, dryness, and tired eyes.

Tear film break-up time, also known as TBUT, improved from 5.0 seconds at baseline to 7.5 seconds after treatment, indicating improved tear film stability.

In a separate allergic eye disorder provocation study, significant irritation reduction was observed within 30 seconds after a single application.

References: btph-032-2012-BAT04, unpublished; btph-015-2018-AAT04-EES09, unpublished.

medEctoin® vs. conventional eye drops

The difference between conventional lubricants and medEctoin® is not about replacing one approach with another. It is about what each approach addresses.

Conventional drops replenish moisture, reduce friction, and help stabilise the tear film. They work mainly at the surface.

medEctoin® works at the cellular level. It helps stabilise membranes under osmotic stress, supports cellular resilience, and may help reduce inflammatory stress signalling. At the same time, it supports tear film stability and helps relieve dryness and ocular discomfort.

Crucially, medEctoin® does not only offer osmoprotection. It also supports hydration and helps stabilise the tear film, while protecting ocular surface cells from hyperosmolar stress.

For formulators, this means one ingredient can help address the dry eye cycle across multiple mechanisms: surface hydration, tear film stability, cellular stress protection, and ocular comfort.

Interested in formulating with medEctoin®?

Get in touch with our team at bd@bitop.de.