Researcher develops strategy to identify antimicrobial drugs that tackle drug-resistant pathogens

A researcher from Purdue University’s College of Veterinary Medicine has developed a novel method of repurposing drugs to act as a potent antimicrobial agent for treatment of both superficial and invasive infections.

Mohamed Seleem’s discovery is being lauded as particularly significant in that the two drugs he has developed show promise in tackling the global issue of bacterial resistant to conventional medicine. The developments that this associate professor of microbiology has made are driven by this urgent need to develop new strains to tackle infectious disease

He comments, “In the United States alone, more than two million individuals are stricken each year with infections caused by multi-drug resistant pathogens. Invasive fungal infections afflict millions of patients annually, resulting in nearly one-and-a-half million deaths. The demand for antifungals is at an all-time high because current antifungal treatments aren’t working very well and can’t be administered very conveniently.”

Seleem identified that while 30% of newly approved FDA drugs and vaccines have been repurposed, no drug has been thoroughly investigated and repurposed for use as an antibacterial or antifungal. He and his team are currently screening 3,200 of the 4,000 available to test, and identifying the most promising candidates for repurposing.

He says: “We take a drug that is being used for, say, heart disease and we re-use it as something like a topical ointment over the skin. The drug hasn’t been changed, but the method of application and purpose has. We have ready information about the drugs from previous research for its initial purpose, but we conduct tests in the new model since they have never been used as an antifungal or antimicrobial, to reveal any information we may need.”

The two most promising drugs he’s found so far, auranofin and ebselen, have been observed to be potent antimicrobial agents capable of killing MRSA, a bacterium responsible for several difficult to treat infections. Auranofin is a treatment for rheumatoid arthritis, while ebselen is intended for treatment for stroke, hearing loss and bipolar disorder.

Seleem adds: “Through our trials we have found that these two drugs have the ability to disrupt adherent staphylococcal biofilms, the most frequent cause of infections originating in hospitals. We’ve found also that they suppress toxin production and key resentment factors and reduce excessive host-inflammatory responses associated with these toxins, significantly reducing bacterial load and enhancing wound healing.

“In addition, both drugs have many advantageous qualities including oral bioavailability, potent bactericidal activity in a clinically achievable range, very low frequency of resistance, and syngertistic activity with conventional antibiotics.”

With plans to research further drug repurposing applications, in fields such as acne and toenail fungus, Seleem is hopeful that his work attracts the attention of the market. His innovation has been patented through the Purdue Research Foundation Office of Technology Commercialization.

Sean Murray