About Staphefekt™

Staphefekt™ is a novel agent for use on intact skin, for the control of Staphylococcus aureus (S. aureus), including methicillin resistant Staphylococcus aureus (MRSA). MRSA is a leading cause of nosocomial infections that have become difficult to treat since it has become resistant to a large variety of conventional antibiotics.

In nature, phages use bacteria to replicate. In this sense, phages can be regarded as bacteria’s natural enemies and endolysins can be viewed as their ’weapons’ to kill their bacterial host. Every two days half of all bacteria on earth are killed by phages. As bacteria evolved into different species, so did their phages. As a result, for every bacterial species there are now phages. When phages replicate, for which they need bacteria as their host, they use enzymes, called endolysins, to open the bacterial cell wall.

Staphefekt™ has been copied from natural phage endolysins. Staphefekt™ is target cell (S. aureus) specific. Commensal bacteria are not affected, and it kills also the strains that have already acquired resistance to conventional antibiotics such as MRSA.

Bacterial killing by Staphefekt™ is independent of the bacterial metabolism. This renders Staphefekt™ a highly effective anti-Staphylococcal agent, highly refractory to resistance induction.


In vitro studies have shown endolysins have two key properties in treating bacterial infections:

  1. Selective rapid killing of specific bacteria

    In vitro data showed that lysis of Staphylococcus aureus (S. aureus) by Staphefekt™ is dose dependent (OD did not differ between MSSA and MRSA (58+/-11.6% vs. 65+/-4,1% with 30 microgram/ml, mean +/- SD, p>0.05) , specific (only 1-15% reduction was observed with the four control strains), and efficient (a thousand-fold reduction of viable bacteria in the first four hours was observed in bactericidal studies).

  2. Very limited likelihood of emerging resistance

    Antibiotic Resistance Induction of resistance against Staphefekt™ could not be achieved in vitro (this was tested with one strain of MSSA and MRSA in duplo by passing 18 incubation cycles with a sub-optimal concentration of Staphefekt™, Mupirocin and Lysostaphin and monitoring the MIC’s at every cycle. No induction of resistance was observed with both strains for Staphefekt™ over time, while a significant increase of MIC’s was observed with mupirocin (4-8 fold increase) and lysostaphin (>4.000-fold increase).


In one case series, after the local application of Staphefekt™ for one week, S. aureus was eradicated from the lesions of all S. aureus positive rosacea patients, while other skin inhabitants remained present. In another case series, lesional S. aureus carriership, symptom relief and corticosteroid use were analysed after Staphefekt™ treatment. In six cases, S. aureus was found in skin cultures before treatment (three patients with constitutional eczema, two with contact dermatitis and one with peri-oral dermatitis). In 5 of 6 patients, symptoms diminished during treatment with Staphefekt™, and patients reported less or no need of corticosteroids.

Staphylococcus aureus

Staphylococcus aureus in Healthcare Settings

General Information about Staphylococcus aureus
Staphylococcus aureus [staf I lō-kok is aw ree us] (S. aureus), is a type of bacteria that about 30% of people carry in their noses. Most of the time, S. aureus does not cause any harm; however, sometimes S. aureus causes infections. In healthcare settings, these infections can be serious or fatal, including:

  • Bacteraemia or sepsis when bacteria spread to the bloodstream.
  • Pneumonia, which predominantly affects people with underlying lung disease including those on mechanical ventilators.
  • Endocarditis (infection of the heart valves), which can lead to heart failure or stroke.
  • Osteomyelitis (bone infection), which can be caused by S. aureus bacteria traveling in the bloodstream, or by direct contact, such as following trauma (puncture wound of foot or intravenous (IV) drug abuse).

S. aureus bacteria can also become resistant to certain antibiotics. These drug-resistant S. aureus infections include: Methicillin-resistant Staphylococcus aureus (MRSA) and Vancomycin-resistant Staphylococcus aureus (VRSA)

Populations at risk for Staphylococcus aureus infection

Anyone can develop a S. aureus infection, although certain groups of people are at greater risk including those with chronic conditions such as diabetes, cancer, vascular disease, eczema, and lung disease. In a healthcare setting, the risk of more serious S. aureus infection is higher because patients often have weakened immune systems or have undergone surgical procedures or had intravenous catheters placed into veins.

Reference: US Centers for Disease Control, 2014

Staphylococcus aureus on human skin

Our skin flora contains billions of bacteria, of which the vast majority protect our skin. A good bacterial balance is necessary to maintain a healthy skin. Disruption of this balance can lead to, or aggravate, skin problems. No other bacterium causes more infections than Staphylococcus aureus. This bacterium is often found on the skin of people and animals. It can lead to serious (internal) infections and inflammation of the skin.

30% of the population carry S. aureus permanently;
50% of the population are regular carriers;
in 20% of the population it is never or hardly ever found.

Staphylococcus aureus presents itself mainly on the skin, in the nose and hair, the armpits hands and perineum. A person’s immune system can help keep these bacteria under control, but when the immune system is weakened or suppressed, or the skin barrier is not intact, S. aureus bacteria can cause infections.

This can result in redness and irritation of the skin, a burning and stinging sensation, spots, pimples, pustules and bumps, and infections. Many of these symptoms are characteristic for acne, eczema, rosacea and skin irritation.