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Immunocidin - Anti-cancer immune system booster

In the 1890's, a New York city physician Dr. William Coley realized cancer cures might be possible - even for late-stage patients - after experiencing a bacterial infection.


He wasn’t the first person to notice this; other physicians in Germany had recorded similar occurrences.


But Dr. Coley was the first to create a new therapy using a mixture of weakened bacteria and began treating hundreds of patients.


The result was remarkably successful.


He also shared the formulation of the so-called “Coley’s toxin” with other doctors, many of whom were also able to help patients.



Coley's toxins used to treat carcinoma, melanoma, sarcoma, blood cancers
Coley's toxins were used to treat operable and inoperable cancers with remarkable results, even compared to today's modern standards. For example, 134 out of 312 inoperable patients survived more than 5 years with the help of his treatment.


It wasn’t known at the time, but Coley had created a form of cancer immunotherapy – a way of fighting cancer by stimulating the patient’s immune system to kill tumor cells.


But unfortunately, due to the introduction of radiation therapy and chemotherapy, Coley’s toxin fell by the wayside. Today, Coley’s toxin is no longer available in the US or Canada.


(Although there have been attempts to revive its production, getting regulatory approval has been impossibly hard).


The nearest thing to Coley’s toxin that is currently clinically used is called BCG (Bacillus Calmette-Guerin), to treat bladder cancer patients. For roughly 70% of patients with early-stage bladder cancer, BCG treatment can effectively stop cancer recurrence.


But because BCG consists of living bovine tuberculosis bacteria, there is a finite possibility of harming the patient with an unwanted infection and also causing serious complications. BCT also tends to be poorly tolerated by some patients.


Is there a safer alternative?


Since the 1960s, researchers have been studying cell walls of bacteria that contain many different compounds that stimulate our immune system.


One of these technologies, called Mycobacterium Cell Wall Fraction (MCWF), has been developed into anticancer immunotherapy - Immunocidin - for veterinary use.


The same technology was developed into a human bladder cancer formulation that progressed to Phase III clinical testing.

In the 1990s, Immunocidin was approved by regulators in the US and Canada for treating mixed mammary tumors and mammary adenocarcinoma in dogs.

A small Canadian company, NovaVive Inc., produces Immunocidin today (at a manufacturing site in Athens, GA).


Can Immunocidin also help dogs with other types of cancer?


MCWF is a strong immunostimulant, with the potential to treat different cancer types, regardless of the location or origin.


(Coley’s toxin was also used to treat many types of cancer)


According to Graeme McRae, the president of NovaVive and one of the inventors of Immunocidin, the product was first tested to treat mammary tumors, even though there were indications that the formulation could be effective for other cancer types. In order to obtain regulatory approval for anticancer therapy, the product must be tested for safety and show some efficacy in a certain tumor type.


New studies are evaluating how Immunocidin might help canine patients with osteosarcoma, bladder cancer, and other tumor types (see below).


It's important to note that veterinarians are permitted to use regulator-approved therapies to treat other types of cancer (“off-label”) if they are comfortable doing so and believe it may help their patients.

What’s in Immunocidin and how does it work?


The active ingredient of Immunocidin is the purified fragments of cell walls from a soilborne bacterium called Mycobacterium phlei. This bacterium is non-pathogenic (does not cause disease) and is commonly found in the environment, including in soil and on the leaves of plants.


The cell walls naturally contain a high concentration compounds that stimulate the immune system, including muramyl dipeptides, trehalose dimycolate, mycolic acid, and glycolipid lipoarabinomannan.


These compounds activate macrophages and other white blood cells and produce cytokines such as IL-6, IL-8, IL-12, IL-18 and TNF-α that help turn on the immune system to fight disease.


The formulation also contains bacterial nucleic acids (e.g. DNA) that have an anti-cancer effect, according to Miriam Cervantes DVM Ph.D., a research scientist at NovaVive.


How is it administered?


Immunocidin was initially approved for intra-tumoral injection treatment.

Newer protocols, currently under study, involve administering the product by IV infusion and as an oral dose.

A dog under Immunocidin therapy for her hemangiosarcoma
Jewell is being treated with Immunocidin for hemangiosarcoma

What kind of side-effects might there be?


Some dogs might experience lethargy, fever, or vomiting, depending on how the product is administered and their level of sensitivity. If Immunocidin is injected into the tumor, there may be some injection site pain and there may be discharge from the tumor as it breaks down.


In what ways might Immunocidin help dogs with cancer?


Immunocidin may:


-help a dog who is not a candidate for receiving surgery or other standard-of-care treatment

-help a dog who has relapsed or did not respond to a prior therapy,

-help recurrence of cancer.


What does its anti-cancer efficacy depend on?


How well it works depends on many factors, including:

-the dog’s overall health especially his or her immune system

-the tumor and tumor microenvironment

-the dosage, how it’s administered, and the frequency of administration.

-whether it is administered before the surgery as a neoadjuvant or after surgery

-whether it is combined with chemotherapy or other therapies