NovoMed Treatment Platform Technologies
In many situations phage therapy can be
superior to antibiotics. This is particularly true in wound care applications,
treatment of osteomyelitis
and chronic infections.
Wound infection is a common risk for patients with chronic nonhealing wounds, causing high
morbidity and mortality. Currently, systemic antibiotic treatment is the therapy of choice,
despite often leading to several side effects and the risk of an insufficient tissue
penetration due to impaired blood supply (typicaly in diabetics).
Antibiotic drug resistance and skin wound infection are a growing concern in all
parts of wound management. The risk of wound infection increases as disorders in the
local environment (e.g., blood supply and eschar) favor bacterial growth rather than
host defense. This can lead to impaired wound healing, bacteremia, or even sepsis and
is associated with high morbidity and mortality.
Today's mainstay for the treatment of wound infection is systemic antibiotic therapy,
even though it is associated with increased development of antibiotic drug resistance and
adverse side effects. Moreover, most systemic agents have poor tissue penetration;
for example, in burn wounds, blood vessels, which normally carry a systemic antibiotic
to the wound, are destroyed.
Topical antibiotics are also very important but currently limited in their clinical use.
To date, no topical broad-spectrum antibiotic with FDA approval is available for the treatment
of skin wound infections.
Treatment of Chronic Wounds
In wound care applications, after normal debridement procedures, bacteriophages are applied
directly to the wound and are highly effective toward clearing Staphylococcus aureus,
Pseudomonas aeruginosa and other pathogens from the wound. Application is performed by
wetting the bandage with a liquid phage preparation.
Amino acid based biodegradable polymers imbedded
with bacteriophages significantly enhance the treatment process, as follows:
- biodegradable polymers are absorbed by the body, leaving no toxic byproducts;
- as the polymers biodegrade on the wound, phages are continuously eluted, providing a
constant application of the medication;
- the amino acids have anti-inflammatory and growth-factor properties; and
- there are significantly fewer bandage changes thereby reducing treatments costs; there is less
pain and discomfort to the patient due to reduced number of bandage changes.
Osteomyelitis is generally treated by the systemic administration of antibiotics and continuous
irrigation after curettage of the lesion, and bone graft is performed secondarily to treat any
bone defect. This treatment is associated with major invasion, and also has adverse effects on
other organs. There is little high quality evidence on the relative effectiveness of various regimens of
antibiotic therapy for osteomyelitis or septic arthritis.
Treatment of Osteomyelitis
Treatment of osteomyelitis with phage therapy typically begins with irrigation (depending the diagnosis),
as is the case with antibiotic therapies, however the patient does not suffer adverse
effects of antibiotics. Given that biodegrable polymers are fully absorbable and produce no toxic byproducts,
the time required for irrigations can be reduced or eliminated by applying the polymers then closing the incision;
the polymers will continue to elute bacteriophages and other medications for an extended period.
A biofilm is a structured consortium of bacteria embedded in a self-produced polymer matrix
consisting of polysaccharide, protein and DNA. Bacterial biofilms cause chronic infections
because they show increased tolerance to antibiotics and disinfectant chemicals as well as
resisting phagocytosis and other components of the body's defence system. The persistence of,
for example, staphylococcal infections related to foreign bodies is due to biofilm formation.
Likewise, chronic Pseudomonas aeruginosa lung infection in cystic fibrosis patients is caused
by biofilm-growing mucoid strains.
Treatment of Chronic Infections
Treatment of chronic infections typically requires "complex therapy", meaning that
a combination of bacteriophages and other medications are expertly combined to help clear the
biofilm and underlying infection. In very difficult cases, treatment can require several
courses of treatment over some years; however, much improvement is realized in cases of chronic UTI's,
chronic prostatitis and chronic sinusits.
Efficacy of Topically Delivered Moxifloxacin against
Wound Infection by Pseudomonas aeruginosa and Methicillin-Resistant Staphylococcus aureus
Antimicrob. Agents Chemother. May 2011 vol. 55 no. 5 2325-2334
F. Jacobsen, C. Fisahn1, M. Sorkin, I. Thiele1, T. Hirsch, I. Stricker, T. Klaassen, A. Roemer, B. Fugmann and L. Steinstraesser
Antibiotic treatment of osteomyelitis: what have we learned from 30 years of clinical trials?
International Journal of Infectious Diseases, Volume 9, Issue 3 , Pages 127-138, May 2005
Luca Lazzarini, Benjamin A. Lipsky, Jon T. Mader
Antibiotic resistance of bacterial biofilms
International Journal of Antimicrobial Agents Volume 35, Issue 4, April 2010, Pages 322–332
Niels Høibya, Thomas Bjarnsholt, Michael Givskov, Søren Molin, Oana Ciofu