Bacteriophages:
Our most powerful tool
to fight against bacteria

Bacteriophages
Our most powerful tool to fight against bacteria

Bacteriophages:
Our most powerful tool
to fight against bacteria

phage
phage
phage

DEFINITION

DEFINITION

What is
a bacteriophage?

What is
a bacteriophage?

Bacteriophages, or simply phages, are the biological predators of bacteria. Found everywhere from your gut to the soil, their main function is to regulate the number of bacteria in microbiomes whether it’s in humans, animals, plants, or in the environment.

Through millions of years of co-evolution with bacteria, phages have become so specialized that they can only detect and target highly specific bacteria, leaving all other cells untouched.

By finding the right phages from the environment, we can design safe and effective medicines to prevent and cure bacterial infections, also known as phage therapy.

Bacteriophages, or simply phages, are the biological predators of bacteria. Found everywhere from your gut to the soil, their main function is to regulate the number of bacteria in microbiomes whether it’s in humans, animals, plants, or in the environment.

Through millions of years of co-evolution with bacteria, phages have become so specialized that they can only detect and target highly specific bacteria, leaving all other cells untouched.

By finding the right phages from the environment, we can design safe and effective medicines to prevent and cure bacterial infections, also known as phage therapy.

10

10

10

MILLION

MILLION

The number of phages in a drop of seawater. Phages are the most abundant biological entities on earth and occur anywhere bacteria are present.

The number of phages in a drop of seawater. Phages are the most abundant biological entities on earth and occur anywhere bacteria are present.

30

30

30

MINUTES

MINUTES

The average time it takes for a phage to eliminate its target bacterium.

The average time it takes for a phage to eliminate its target bacterium.

1

1

1

TARGET

TARGET

A phage is usually effective against a single bacterial species. Phages do not interact with human or animal cells.

A phage is usually effective against a single bacterial species. Phages do not interact with human or animal cells.

100+

100+

100+

YEARS AGO

YEARS AGO

French microbiologist Félix d’Hérelle coined the term “bacteriophage,” meaning “bacteria eater.”

French microbiologist Félix d’Hérelle coined the term “bacteriophage,” meaning “bacteria eater.”

MECHANISM

MECHANISM

How do phages work?

How do phages work?

phage
phage
phage

01

IDENTIFY BACTERIAL TARGETS

The phage scans for their specific bacterial target and attaches to unique receptors on the bacterium's surface.

01

IDENTIFY BACTERIAL TARGETS

The phage scans for their specific bacterial target and attaches to unique receptors on the bacterium's surface.

02

BACTERIAL CELL TAKEOVER

The phage injects its DNA, which hijacks the bacterium's machinery to mass-produce new phages.

02

BACTERIAL CELL TAKEOVER

The phage injects its DNA, which hijacks the bacterium's machinery to mass-produce new phages.

03

BACTERIAL LYSIS

In around 30 minutes, the bacterium bursts open to release hundreds of newly-made phages to repeat the cycle.

03

BACTERIAL LYSIS

In around 30 minutes, the bacterium bursts open to release hundreds of newly-made phages to repeat the cycle.

03

BACTERIAL LYSIS

In around 30 minutes, the bacterium bursts open to release hundreds of newly-made phages to repeat the cycle.

04

CYCLE COMPLETE

Once target bacteria are eliminated, the phages naturally diminish and are cleared by the immune system.

04

CYCLE COMPLETE

Once target bacteria are eliminated, the phages naturally diminish and are cleared by the immune system.

PHAGE 101

Phage Classification

lytic phage
lytic phage

01

LYTIC

Lytic phages rapidly destroy bacteria through lysis, which is the release of an enzyme that breaks down cell walls.

temperate phage
temperate phage

02

TEMPERATE

Temperate phages lie dormant inside bacterial DNA for varying amounts of time before eventually destroying the bacteria through cell lysis.

Phage therapy only uses lytic phages for their ability to eliminate bacteria quickly.

FUTURE applicationS

The Future of Phage Therapy

Phages hold extraordinary potential to transform how we protect life from bacterial threats. Most urgently fighting antibiotic-resistant superbugs in humans and preventing disease in livestock. However their potential applications have a great range.

TIMELINE

TIMELINE

TIMELINE

A history
of phage therapy

A history
of phage therapy

For the past 100 years, phages have journeyed from groundbreaking discovery to near abandonment. Now with advancements in microbiology and artificial intelligence, they are emerging as a solution

to the antimicrobial resistance (AMR) crisis.

1915-1917

Félix d'Hérelle and Frederick Twort independently discover bacteriophages.

1917

Félix d’Hérell uses phages to treat dysentery patients successfully,
the first recorded phage therapy.

1928

Alexander Fleming discovers penicillin.

1940s

The antibiotic era begins as penicillin's broad-spectrum effectiveness and scalable mass production overshadow phage therapy in the West.

1950s

Antibiotics begin widespread use as growth promoters in animal farming.

1940s-1990s

The Soviet Union and Eastern Europe continue developing phage therapy while the West abandons phage research.

1990s

The AMR crisis (antimicrobial resistance) sparks renewed interest in phage therapy.

2006

The European Union bans antibiotic use as a growth promoter in animal farming.

2015

DeepMind's AlphaFold shows AI’s ability to tackle complex biological structure prediction problems, paving the way for new use cases for phage therapy.

2025

Alphagos receives world's first phage platform authorization for use in animal farming.

1915-1917

Félix d'Hérelle and Frederick Twort independently discover bacteriophages.

1917

Félix d’Hérell uses phages to treat dysentery patients successfully,
the first recorded phage therapy.

1928

Alexander Fleming discovers penicillin.

1940s

The antibiotic era begins as penicillin's broad-spectrum effectiveness and scalable mass production overshadow phage therapy in the West.

1950s

Antibiotics begin widespread use as growth promoters in animal farming.

1940s-1990s

The Soviet Union and Eastern Europe continue developing phage therapy while the West abandons phage research.

1990s

The AMR crisis (antimicrobial resistance) sparks renewed interest in phage therapy.

2006

The European Union bans antibiotic use as a growth promoter in animal farming.

2015

DeepMind's AlphaFold shows AI’s ability to tackle complex biological structure prediction problems, paving the way for new use cases for phage therapy.

2025

Alphagos receives world's first phage platform authorization for use in animal farming.

FAQS

FAQS

Frequently asked questions

Frequently asked questions

What is phage therapy?

Phage therapy is the use of bacteriophages to treat pathogenic bacterial infections.

What is phage therapy?

Phage therapy is the use of bacteriophages to treat pathogenic bacterial infections.

Are phages safe for humans?

Phages have an excellent safety profile because they're naturally occurring and highly selective. They only attack specific bacterial targets, leaving human cells and beneficial bacteria untouched.

Are phages safe for humans?

Phages have an excellent safety profile because they're naturally occurring and highly selective. They only attack specific bacterial targets, leaving human cells and beneficial bacteria untouched.

What happens to all the phages after a bacterial infection is treated?

Phages cannot survive without their host bacteria. The body’s immune system naturally clears out any remaining phages that are no longer needed. This is done by white blood cells responsible for clearing out debris and dead cells from the body (macrophages).

What happens to all the phages after a bacterial infection is treated?

Phages cannot survive without their host bacteria. The body’s immune system naturally clears out any remaining phages that are no longer needed. This is done by white blood cells responsible for clearing out debris and dead cells from the body (macrophages).

Are animals treated with phages safe to eat?

Yes. Humans and animals are naturally in contact with high amounts of bacteriophages produced natively in the gastrointestinal tract as well as food, water, and the environment.

Are animals treated with phages safe to eat?

Yes. Humans and animals are naturally in contact with high amounts of bacteriophages produced natively in the gastrointestinal tract as well as food, water, and the environment.

Can bacteriophages replace antibiotics?

Phage therapy represents a paradigm shift in treating bacterial infections and can greatly reduce the need for antibiotics. It is unlikely there will ever be one tool capable of treating all bacterial infections, but phages are a powerful tool to prevent and cure bacterial infections in addition to antibiotics, vaccinations, and good hygiene practices.

Can bacteriophages replace antibiotics?

Phage therapy represents a paradigm shift in treating bacterial infections and can greatly reduce the need for antibiotics. It is unlikely there will ever be one tool capable of treating all bacterial infections, but phages are a powerful tool to prevent and cure bacterial infections in addition to antibiotics, vaccinations, and good hygiene practices.

Why isn’t phage therapy already widely available?

The main reasons are technological development and regulatory pathways. Phage therapy couldn't be scaled initially because scientists lacked both the laboratory tools for precise phage identification and the technology to design personalized phage medicines quickly enough. Advances in microbiology and artificial intelligence are now changing this. 

The biological nature of phages also requires a different regulatory approach than traditional antibiotics (a chemical). Regulatory agencies around the world are actively working to establish pathways for this promising technology in order to relieve the burden of the antimicrobial resistance (AMR) crisis.

Why isn’t phage therapy already widely available?

The main reasons are technological development and regulatory pathways. Phage therapy couldn't be scaled initially because scientists lacked both the laboratory tools for precise phage identification and the technology to design personalized phage medicines quickly enough. Advances in microbiology and artificial intelligence are now changing this. 

The biological nature of phages also requires a different regulatory approach than traditional antibiotics (a chemical). Regulatory agencies around the world are actively working to establish pathways for this promising technology in order to relieve the burden of the antimicrobial resistance (AMR) crisis.

Can I use it on my pets?

Today Alphagos is only for use on farms by prescription of a veterinarian.

Can I use it on my pets?

Today Alphagos is only for use on farms by prescription of a veterinarian.