Bacteriophage Products Research Articles

Personalized bacteriophage therapy outcomes for 100 consecutive cases: a multicentre, multinational, retrospective observational study

In contrast to the many reports of successful real-world cases of personalized bacteriophage therapy (BT), randomized controlled trials of non-personalized bacteriophage products have not produced the expected results. Here we present the outcomes of a retrospective observational analysis of the first 100 consecutive cases of personalized BT of difficult-to-treat infections facilitated by a Belgian consortium in 35 hospitals, 29 cities and 12 countries during the period from 1 January 2008 to 30 April 2022. We assessed how often personalized BT produced a positive clinical outcome (general efficacy) and performed a regression analysis to identify functional relationships. The most common indications were lower respiratory tract, skin and soft tissue, and bone infections, and involved combinations of 26 bacteriophages and 6 defined bacteriophage cocktails, individually selected and sometimes pre-adapted to target the causative bacterial pathogens. Clinical improvement and eradication of the targeted bacteria were reported for 77.2% and 61.3% of infections, respectively. In our dataset of 100 cases, eradication was 70% less probable when no concomitant antibiotics were used (odds ratio = 0.3; 95% confidence interval = 0.127–0.749). In vivo selection of bacteriophage resistance and in vitro bacteriophage–antibiotic synergy were documented in 43.8% (7/16 patients) and 90% (9/10) of evaluated patients, respectively. We observed a combination of antibiotic re-sensitization and reduced virulence in bacteriophage-resistant bacterial isolates that emerged during BT. Bacteriophage immune neutralization was observed in 38.5% (5/13) of screened patients. Fifteen adverse events were reported, including seven non-serious adverse drug reactions suspected to be linked to BT. While our analysis is limited by the uncontrolled nature of these data, it indicates that BT can be effective in combination with antibiotics and can inform the design of future controlled clinical trials. BT100 study, ClinicalTrials.gov registration: NCT05498363.

HTA3 Health Technology Assessment Requirements: Sensitive to Bacteriophage Products or Too Resistant to Change?

HTA3 Health Technology Assessment Requirements: Sensitive to Bacteriophage Products or Too Resistant to Change?

Gender-Responsive Design of Bacteriophage Products to Enhance Adoption by Chicken Keepers in Kenya.

Women and men keeping chickens in Kenya aspire to have a source of income, feed their families healthy food, and grow their businesses. Managing animal diseases and minimizing input costs enable their success. This study uses qualitative methods to recommend design opportunities for a veterinary product under development in Kenya that contains bacteriophages (phages) that target pathogenic Salmonella strains responsible for fowl typhoid, salmonellosis, and pullorum in chickens and foodborne illness in people. Our findings revealed the interplay between gender and two production systems: free-range and semi-intensive. Chicken keepers in both systems could benefit from phages combined with the orally administered Newcastle disease vaccine, one of the most commonly used preventive veterinary interventions, or phages as a treatment for fowl typhoid. Oral administration is less labor intensive, with greater benefits for women who have less control over family labor and reported doing more care tasks themselves. Men in free-range systems usually pay for veterinary inputs. In semi-intensive production systems, a phage-based product used prophylactically could be an alternative to expensive, intramuscular fowl typhoid vaccines. Keeping layers was common for women in semi-intensive systems, as they are more economically impacted by reduced laying caused by bacterial diseases. Awareness of zoonoses was low, but men and women were concerned about the negative health effects of drug residues in meat and eggs. Therefore, highlighting the lack of a withdrawal period for a phage product may appeal to customers. Antibiotics are used to both treat and prevent diseases, and phage products will need to do both to compete in the Kenyan market. These findings guide the ongoing design of a phage-based product with the goal of introducing a new veterinary product that meets the diverse needs of chicken keepers in Africa and serves as an alternative or complement to antibiotics.

Role of Bacteriophages for Optimized Health and Production of Poultry

The poultry sector is facing infections from Salmonella, Campylobacter, Listeria and Staphylococcus spp., and Escherichia coli, that have developed multidrug resistance aptitude. Antibiotics cause disturbances in the balance of normal microbiota leading to dysbiosis, immunosuppression, and the development of secondary infections. Bacteriophages have been reported to lower the colonization of Salmonella and Campylobacter in poultry. The specificity of bacteriophages is greater than that of antibiotics and can be used as a cocktail for enhanced antibacterial activity. Specie-specific phages have been prepared, e.g., Staphylophage (used against Staphylococcus bacteria) that specifically eliminate bacterial pathogens. Bacteriophage products, e.g., BacWashTM and Ecolicide PX have been developed as antiseptics and disinfectants for effective biosecurity and biosafety measures. The success of phage therapy is influenced by time to use, the amount used, the delivery mechanism, and combination therapy with other therapeutics. It is a need of time to build a comprehensive understanding of the use of bacteriophages in poultry production. The current review thus focuses on mechanisms of bacteriophages against poultry pathogens, their applications in various therapeutics, impacts on the economy, and current challenges.

Manufacturing Bacteriophages (Part 2 of 2): Formulation, Analytics and Quality Control Considerations.

Within this second piece of the two-part series of phage manufacturing considerations, we are examining the creation of a drug product from a drug substance in the form of formulation, through to fill-finish. Formulation of a drug product, in the case of bacteriophage products, is often considered only after many choices have been made in the development and manufacture of a drug substance, increasing the final product development timeline and difficulty of achieving necessary performance parameters. As with the preceding review in this sequence, we aim to provide the reader with a framework to be able to consider pharmaceutical development choices for the formulation of a bacteriophage-based drug product. The intent is to sensitize and highlight the tradeoffs that are necessary in the development of a finished drug product, and to be able to take the entire spectrum of tradeoffs into account, starting with early-stage R&D efforts. Furthermore, we are arming the reader with an overview of historical and current analytical methods with a special emphasis on most relevant and most widely available methods. Bacteriophages pose some challenges that are related to but also separate from eukaryotic viruses. Last, but not least, we close this two-part series by briefly discussing quality control (QC) aspects of a bacteriophage-based product, taking into consideration the opportunities and challenges that engineered bacteriophages uniquely present and offer.

Efficacy of phage therapy in pigs: systematic review and meta-analysis.

Limits on the use and efficacy of various antibiotics coupled with negative consumer perception of the practice have together spurred substantial research into compounds that could reduce the use antibiotics to control bacterial diseases in pigs. Bacteriophages are often among such potential compounds, and various groups have examined the efficacy of bacteriophages or bacteriophage products in limiting transmission or colonization of targeted bacteria. The study presented here provides a systematic review of such studies followed by a meta-analysis of aggregated data produced by each study. The data set was limited to inputs (n = 19; 576 total observations) from studies where: 1) live pigs were inoculated with a known quantity of challenge bacteria; 2) challenged animals were treated with a known quantity of phages; 3) concentrations of the challenge bacteria were measured in different tissues/fluids following phage treatment; and 4) SD (or SE to allow calculation of SD) was reported. Concentrations of challenge bacteria were significantly lower in phage-treated pigs versus challenged but untreated pigs (P < 0.0001; effect size = −1.06 1log10 colony-forming units [CFU]/g). The effect size of phage treatment was significantly greater (P < 0.05) in samples collected 48 to 96 h following phage treatment versus those collected ≤ 24 h following phage treatment. Likewise, effect size of phage treatment was significantly greater in piglets versus market-weight pigs. Across observations, phage treatment effect sizes were greatest (P < 0.01) in fecal samples versus ileal or cecal samples. Taken together, these data indicate that phage treatment can significantly reduce the concentrations of targeted bacteria in pigs; scenarios exist, however, where phage treatment could predictably be more or less effective.

Efficacy of commercial bacteriophage products against ESKAPE pathogens

The ever-rising prevalence of multidrug-resistant bacteria necessitates the search for a therapeutic alternative to antibiotics. Using therapeutic products based on virulent bacteriophages might provide such an alternative. The aim of our study was to evaluate the efficacy of commercial phage products and natural bacteriophage monoisolates recovered from environmental sources against clinical strains of Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, and Pseudomonas aeruginosa. We compiled a collection of 147 strains that were subsequently genotypes using the MLST method. The efficacy of bacteriophages was evaluated in spot tests. The highest efficacy was demonstrated by "Staphylococcal bacteriophage" (86%, effective against S. aureus), "Purified polyvalent pyobacteriophage" (87.8%, effective against K. pneumoniae), and a group of phage products against P. aeruginosa, including "Pseudomonas aeruginosa bacteriophage" (87.5%), "Complex pyobacteriophage" (79.5–90%) and "Purified polyvalent pyobacteriophage" (90–92.5%). The efficacy of "Intesti bacteriophage", which targets E. faecium, was 4.2%. The efficacy of commercial phage products against S. aureus and K. pneumoniae was higher than the efficacy of individual phage monoisolates (60% for the S. aureus phage vB_SauP-436-3w and 5.9% for the K. pneumoniae phage vB_Kp_M_ Seu621). Thus, all tested commercial phage products were highly effective against P. aeruginosa, K. pneumoniae and S. aureus. There are no commercial phage products on the market against other ESKAPE pathogens, including Acinetobacter baumannii and Enterobacter cloacae. Besides, there are no effective phage products against E. faecium. This dictates the need for new effective bacteriophages against these species.

Bacteriophage Therapy: Developments and Directions.

In an era of proliferating multidrug resistant bacterial infections that are exhausting the capacity of existing chemical antibiotics and in which the development of new antibiotics is significantly rarer, Western medicine must seek additional therapeutic options that can be employed to treat these infections. Among the potential antibacterial solutions are bacteriophage therapeutics, which possess very different properties from broad spectrum antibiotics that are currently the standard of care, and which can be used in combination with them and often provide synergies. In this review we summarize the state of the development of bacteriophage therapeutics and discuss potential paths to the implementation of phage therapies in contemporary medicine, focused on fixed phage cocktail therapeutics since these are likely to be the first bacteriophage products licensed for broad use in Western countries.

Approaches to optimize therapeutic bacteriophage and bacteriophage-derived products to combat bacterial infections.

The emerging occurrence of antibiotic-resistant bacterial pathogens leads to a recollection of bacteriophage as antimicrobial therapeutics. This article presents a short overview of the clinical phage application including their use in military medicine and discusses the genotypic and phenotypic properties of a potential “ideal” therapeutic phage. We describe current efforts to engineer phage for their improved usability in pathogen treatment. In addition, phage can be applied for pathogen detection, selective drug delivery, vaccine development, or food and surface decontamination. Instead of viable phage, (engineered) phage-derived enzymes, such as polysaccharide depolymerases or peptidoglycan-degrading enzymes, are considered as promising therapeutic candidates. Finally, we briefly summarize the use of phage for the detection and treatment of “Category A priority pathogens”.

Evaluation of bacteriophage products against burn wound Methicillin-resistant Staphylococcus aureus (MRSA) infections

Abstract Background The major problem in the management of burn wounds are infections. Methicillin-resistant Staphylococcus aureus (MRSA) is one of the major cause of infection in burn wounds. Antibiotic resistant bacteria around the world has become a major therapeutic challenge. Bacteriophages and their lysine are suggested as an antimicrobial alternative agent. Phage display technique is suggested for production of recombinant lysine by Nano carrier technology. The approach of this study was to evaluate the potential of recombinant Nano phage efficacy in MRSA burn wound infection in vivo. Materials and methods The 3rd degree burn wounds were induced in 54 rats and infected with MRSA ATCC 33591 via the topical route in four groups. Burn wound size was measured in 0, 14, 21, 28 days. The efficacy of Nano phage gel was assessed on the basis of percentage collagen deposition, granulation tissue, neovascularization, fibroblastic maturity, re-epithelization, and scar formation in rats following treatment in 14, 21, 28 days. Results The results showed that the percentage of wound size were 3 cm on base line day and the average macroscopic wound healing rates were increased in the prevention groups receiving the recombinant Nano phage gel and natural phage gel, in the treatment groups with secondary infection receiving the recombinant Nano phage gel and the natural phage gel, and in the two control groups respectively. The average microscopic wound healing rates were increased in the prevention groups receiving the recombinant Nano phage gel and natural phage gel, in the treatment groups with secondary infection receiving the recombinant Nano phage gel and the natural phage gel, and in the two control groups respectively. Conclusions In conclusion the recombinant Nano phage gel is efficacy to treat and prevent MRSA burn wound infection.

Elaboration of Pharmacopoeial Quality Standards for Bacteriophage Products

Bacteriophages are novel safe and efficacious medicinal products that are used for treatment of intestinal infections and purulent inflammations. The fact that virulent phages can be adapted to fight antibiotic-resistant bacterial strains makes this group of medicines a promising means of treatment of infections associated with medical interventions. The elaboration of quality standards for bacteriophage products will enable alignment of the quality requirements and test methods. There are no monographs on bacteriophage products in pharmacopoeias of other countries, therefore, the development of general chapters on groups of test methods used in bacteriophage quality control and monographs on bacteriophages for the State Pharmacopoeia of the Russian Federation (Ph. Rus.) was a very relevant and timely initiative. The aim of the study was to elaborate pharmacopoeial quality standards for bacteriophages approved in the Russian Federation for therapeutic and prophylactic indications. The authors of the study analysed product specification files and master production records for bacteriophages produced in the Russian Federation. They determined common GMP-compliant production steps, the selection criteria for bacteriophage strains and bacteria production strains, and cultivation and storage conditions. The authors standardised bacteriophage quality parameters and brought the test methods in line with the test procedures described in the Ph. Rus., 14th ed. The study summarised test methods used for identification of bacteriophages and determination of their specific activity. The main results of the study were included into the general monograph «Bacteriophages» and individual monographs on bacteriophage products that were included into the current edition of the Ph. Rus. Further studies and elaboration of new quality standards for mono- and multicomponent bacteriophage products, and the use of such products in clinical practice will improve prophylaxis and treatment of various infectious diseases.

Bacteriophage Production in Compliance with Regulatory Requirements.

In this chapter we review bacteriophage production requirements to help institutions, which wish to manufacture bacteriophage products for human use in compliance with the applicable regulatory expectancies, defining production processes and implementing relevant controls ensuring quality, safety, and efficacy of the final products. The information disclosed in this chapter can also serve as a basis for discussions with competent authorities regarding the development of expedited bacteriophage product development and licensing pathways, including relevant and pragmatic requirements, and allowing for the full exploitation of bacteriophages as natural controllers of bacterial populations.

Therapeutic use of bacteriophages in animals and in foods to reduce contamination.

Abstract Bacteriophages are viruses that are able to infect and kill bacterial cells. This capability indicates that they may have the potential to become new antibacterial agents, as an alternative to antibiotics. Yet, while bacteriophages are relatively new to Western researchers, they have been extensively used in the former Eastern Block and its successors, including use in human clinical medicine. Western research on this topic is far more limited. Bacteriophage products have recently been licensed in the USA for control of two different bacteria: Listeria monocytogenes and Escherichia coli O157:H7. Neither of these products is, however, approved for direct administration to humans or animals. The use of bacteriophages to treat bacterial infections in humans or animals is a much more complex issue, but there has been a considerable amount of research into this field, and results are quite promising. Bacteriophage therapy and prevention of bacterial pathogens has been assessed in numerous species, and animals are also used as models for human disease. The behaviour of bacteriophages is, however, not as predictable in vivo as it is in artificial laboratory models. There is also concern regarding possible undesirable outcomes of bacteriophage therapy, such as the development of bacterial resistance to bacteriophages, and even the possibility of transfer of virulence or resistance genes, via bacteriophages, into other bacteria. Therefore, extensive research is still required into the behaviour of bacteriophages in vivo , but research to date shows considerable promise.

5580725 Method of eliminating genetic routes for bacteriophage evolution and products produced thereby : Klaenhammer Todd R; Moineau Sylvai Raleigh, NC, United States Assigned to North Carolina State University

5580725 Method of eliminating genetic routes for bacteriophage evolution and products produced thereby : Klaenhammer Todd R; Moineau Sylvai Raleigh, NC, United States Assigned to North Carolina State University

Inactive T4 progeny virus formation in a temperature-sensitive mutant of Escherichia coli K12

We describe a mutant (W22) of Escherichia coli K12 W3350 in which viable T-even phage production is temperature sensitive. The uninfected bacterium is indistinguishable from the wild-type parental strain at both low and high temperatures. We show by electron microscopical observations and in vitro complementation that at the nonpermissive temperature viral particles are produced that are unable to infect a T4-sensitive host because of a functional defect in the tail fibers. The rest of the particle is normal and can be activated by incubation with fiber containing extracts. Necessary and sufficient for the expression of temperature sensitivity is the synthesis of early bacteriophage products at the nonpermissive temperature. We suggest that a host protein is involved in viral morphogenesis.