Provectus Biopharmaceuticals Announces Publication of Activity of Pharmaceutical-Grade Rose Bengal Sodium (RBS) Against Colistin-Resistant Gram-Negative Bacteria

Rhea-AI Summary

Provectus has announced new preclinical research published in The Journal of Antibiotics demonstrating that its pharmaceutical-grade rose bengal sodium (RBS) effectively inhibits the growth of colistin-resistant gram-negative (G-) bacteria and exhibits rapid-killing characteristics. Colistin is recognized as a last-resort treatment for severe bacterial infections and is classified by the WHO as critically important to human health. The research, led by Dr. Michio Kurosu at the University of Tennessee Health Science Center, shows that Provectus' RBS formulation (HP-RBf) has significant potential against these resistant pathogens. This reinforces the capability of RBS to contribute to combination therapies in treating infectious diseases, as stated by Dominic Rodrigues, Vice Chair of Provectus’ Board of Directors.

Positive

• Research validates RBS's effectiveness against colistin-resistant G- bacteria.
• Potential for combination therapy offers a strategic advantage in infectious disease treatment.

Negative

• None.

• Colistin is used as last-resort treatment for bacterial infections
• Provectus’ RBS effectively inhibits growth of colistin-resistant G- bacteria
• RBS also possesses rapid-killing feature
  

KNOXVILLE, TN, April 20, 2023 (GLOBE NEWSWIRE) -- Provectus (OTCQB: PVCT) today announced that preclinical research on the Company’s pharmaceutical-grade rose bengal sodium drug substance against colistin-resistant gram-negative (G-) bacteria was published in The Journal of Antibiotics, a medical periodical by Nature Portfolio for the Japan Antibiotics Research Association. Colistin is used as a last-resort treatment for infections when other drugs fail. The World Health Organization (WHO) classifies colistin as “highest priority critically important for human health.”¹

The article, entitled “Antibacterial effect of rose bengal against colistin-resistant gram negative bacteria,” may be accessed at: https://www.nature.com/articles/s41429-023-00622-1 (subscription required).

Led by Michio Kurosu, PhD, Professor, Department of Pharmaceutical Sciences, College of Pharmacy, this research work was conducted under a sponsored research agreement between the University of Tennessee Health Science Center in Memphis and Provectus. Dr. Kurosu and his colleagues showed that a formulation of Provectus’ pharmaceutical-grade, high-purity, RBS drug substance (abbreviated as “HP-RBf” in the article):

• Effectively inhibited the growth of colistin-resistant G- bacteria, and
  
• Possesses a rapid-killing feature for colistin-resistant G- bacteria.
  

Dr. Kurosu and his colleagues previously published preclinical research on HP-RBf against Gram-positive (G+) bacteria in Molecules, an open-access journal of chemistry, entitled “Antibacterial Activity of Pharmaceutical-Grade Rose Bengal: An Application of a Synthetic Dye in Antibacterial Therapies:”

• HP-RBf killed a battery of G+ bacteria, including drug-resistant strains, at low concentrations in a few minutes under fluorescent, LED, and natural light,
  
• HP-RBf eradicated G+ bacterial biofilms, including drug-resistant strains,
  
• The frequency that G+ bacteria spontaneously developed resistance to HP-RBf was extremely low,
  
• Based on toxicity data, HP-RBf may be feasible as an anti-infective drug for the treatment of skin and soft tissue infections involving multidrug-resistant microbial invasion of the skin, and
  
• Based on a whole-genome sequencing and analysis of a generated HP-RBf-resistant mutant, antibacterial activity of HP-RBf under dark conditions may implicate multiple cooperative mechanisms of action.
  

Dominic Rodrigues, Vice Chair of the Company’s Board of Directors said, “We are grateful to Dr. Kurosu and his colleagues for their innovative scientific research showing the activity of Provectus’ pharmaceutical-grade rose bengal sodium drug substance against colistin-resistant gram-negative bacteria.”

Mr. Rodrigues added, “This new research further validates a key trait of our rose bengal sodium molecule, which is the ability to meaningfully and substantially contribute to the effectiveness of a combination therapy treatment. Provectus has now demonstrated this molecular characteristic of our rose bengal sodium preclinically and/or clinically in oncology, dermatology, and infectious diseases, establishing once again the veracity of Provectus’ small molecule halogenated xanthene medical science.”

Reference

1. Critically important antimicrobials for human medicine, 6^th revision. Geneva: World Health Organization; 2019.

About Provectus

Provectus Biopharmaceuticals, Inc. (Provectus or the Company) is a clinical-stage biotechnology company developing immunotherapy medicines for different diseases that are based on a class of synthetic small molecule immuno-catalysts called halogenated xanthenes (HXs). Provectus’ lead HX molecule is named rose bengal sodium (RBS).

The Company’s proprietary, patented, pharmaceutical-grade RBS is the active pharmaceutical ingredient (API) in the drug product candidates of Provectus’ clinical development programs and preclinical formulations of the Company’s drug discovery programs. Provectus’ pharmaceutical-grade RBS displays different therapeutic effects at different concentrations and can be formulated for delivery by different routes of administration. The International Nonproprietary Names Expert Committee of the World Health Organization selected “rose bengal sodium” for the nonproprietary name of the Company’s API.

RBS may target disease in a bifunctional manner. Direct contact may lead to cell death or repair depending on the disease being treated and the concentration of Provectus’ RBS utilized in the treatment. Multivariate immune signaling, activation, and response may follow that may manifest as stimulatory, inhibitory, or both.

The Company believes that it is the first entity to advance an RBS formulation into clinical trials for the treatment of a disease. Provectus believes that it is the first and only entity to date to successfully, reproducibly, and consistently make pharmaceutical-grade RBS at a purity of nearly 100%.

Provectus’ small molecule HX medical science platform includes clinical development programs in oncology, dermatology, and ophthalmology; proof-of-concept in vivo drug discovery programs in oncology, hematology, wound healing, and animal health; and preclinical in vitro drug discovery programs in infectious diseases and tissue regeneration and repair.

Information about the Company’s clinical trials can be found at the National Institutes of Health (NIH) registry, ClinicalTrials.gov. For additional information about Provectus, please visit the Company’s website at www.provectusbio.com.

FORWARD-LOOKING STATEMENTS

The information in this press release may include “forward-looking statements,” within the meaning of U.S. securities legislation, relating to the business of Provectus and its affiliates, which are based on the opinions and estimates of Company management and are subject to a variety of risks and uncertainties and other factors that could cause actual events or results to differ materially from those projected in the forward-looking statements. Forward-looking statements are often, but not always, identified by the use of words such as “seek,” “anticipate,” “budget,” “plan,” “continue,” “estimate,” “expect,” “forecast,” “may,” “will,” “project,” “predict,” “potential,” “targeting,” “intend,” “could,” “might,” “should,” “believe,” and similar words suggesting future outcomes or statements regarding an outlook.

The safety and efficacy of the agents and/or uses under investigation have not been established. There is no guarantee that the agents will receive health authority approval or become commercially available in any country for the uses being investigated or that such agents as products will achieve any particular revenue levels.

Due to the risks, uncertainties, and assumptions inherent in forward-looking statements, readers should not place undue reliance on these forward-looking statements. The forward-looking statements contained in this press release are made as of the date hereof or as of the date specifically specified herein, and Provectus undertakes no obligation to update or revise any forward-looking statements, whether as a result of new information, future events or otherwise, except in accordance with applicable securities laws. The forward-looking statements are expressly qualified by this cautionary statement.

Risks, uncertainties, and assumptions include those discussed in the Company’s filings with the SEC, including those described in Item 1A of the Company’s Annual Report on Form 10-K for the year ended December 31, 2022 and Provectus’ Quarterly Report on Form 10-Q for the quarter ended September 30, 2022.

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Contact:

Provectus Biopharmaceuticals, Inc.
Heather Raines, CPA
Chief Financial Officer
Phone: (866) 594-5999

FAQ

What is the significance of Provectus' recent study on PVCT?

Provectus' study highlights the effectiveness of its RBS drug against colistin-resistant gram-negative bacteria, a major concern in antibiotic resistance.

When was the research on Provectus' RBS published?

The research was published on April 20, 2023.

What is the main finding of the research conducted by Provectus?

The research found that Provectus' RBS effectively inhibits and rapidly kills colistin-resistant G- bacteria.

Who led the research on Provectus' RBS?

The research was led by Dr. Michio Kurosu at the University of Tennessee Health Science Center.

What does the WHO say about colistin?

The WHO classifies colistin as critically important for human health, often used as a last-resort antibiotic.