Periodic Reporting for period 2 - LeadtoTreat (Targeted Nano-formulations for Treatment of MRSA: A multicomponent platform for nano-formulated treatment of resistant microbial infections)
Reporting period: 2023-03-01 to 2024-08-31
The primary objective of LeadtoTreat is to develop a flexible, targeted nanoparticle system for delivery of synergistic antimicrobial treatments, demonstrated with MRSA targeting nano-formulations of difficult-to-formulate-drug leads towards multidrug resistant S. aureus bacterial infections.
This platform technology will be demonstrated by converting a highly active, but water insoluble and protein binding, novel compound into targeted nano-formulations for treatment of methicillin-resistant Staphylococcus aureus (MRSA) infections with proven in vivo and in vitro safety. Furthermore, LeadtoTreat aims to identify novel synergistic combinations of antibiotics and potentiators and convert these into highly active targeted nano-formulations for treatment of MRSA infections.
The treatment of bacterial infections on a global scale is facing the enormous challenge of rapidly increasing predominance of antibiotic resistant strains. It is estimated that up to 50,000 lives in Europe and the US and 700,000 lives globally are lost each year due to drug-resistant microbes. These numbers are increasing rapidly, and by 2050, 10 million lives a year and a cumulative 100 trillion USD of economic output are at risk due to the rise of drug-resistant infections. Particularly MRSA infections are a great threat worldwide, especially in hospitalized patients. MRSA colonizes typically in surgical sites, wounds and burns, bone joints, the respiratory system, and implants, and can develop into infection of the central nervous system and in the blood stream (bacteraemia).
The work in research period 2 has covered an extensive screening of the activity of antibiotics and potentiators against the entire test panel of MRSA strains established in the first research period or on subsets of it. Screening has been performed both with combinations of two antibiotics and combinations of antibiotics and potentiators, and a few promising synergistic combinations have been revealed. For the present reporting period, our focus has been on identifying robust combinations of antibiotics with synergistic effects.
All immunization campaigns were finished by partner NTB in research period 2. The general immune response from the animals was very good and nanobody candidates against the targets have been identified, selected and produced for validation. A total of 15 nanobodies were selected for further work in the project. The production and optimization of these candidates will be performed in the coming months.
Work preparing suitable POPZ materials for effective encapsulation has continued in research period 2. Focus has been on developing the best possible PEG-based POPZ for encapsulation. Some challenges with reproducibility of POPZ synthesis (particularly yield and molecular weight) have caused some delays but have been addressed and solved. Alternative to PEG as the hydrophilic substituent and immune masking agent, have been evaluated.
Different protocols for production of nanoparticles have been developed and the effects on the size, size distribution and encapsulation efficiency have been evaluated. In this work, some batch effects of the constituents have been observed. Although issues of behavioral differences are resolved, these issues have caused some delay in the delivery of formulations to further in vitro and in vivo testing. We have also worked on the translational aspect of nano-formulation. For that reason, we have verified that the particles have very long stability both with regard to physical (size) and chemical stability.
Methods for in vitro evaluation of antibiotic effect of nano-formulations as well as for in vitro safety testing have been evaluated and are now ready for testing of new formulations. The in vivo work in the project is delayed due to the unforeseen technical challenges in material for formulations and formulation work. The in vivo work has been rescheduled and we would like to emphasize that it is feasible to complete all in vivo work within the project time.
The project has also explored alternatives to PEG for immune masking of nano-formulations. Furthermore, the project has generated new nanobodies with potential interests beyond the the LeadtoTreat project. In the coming period will the antibiotic nano-formulations be further developed and optimized regarding in vitro and in vivo efficacy and safety. In the coming period will the project also focus on evaluation of potential means for exploitation of the results. Options will include evaluation of further public funding from national and international funding bodies, e.g. application to EIC Accelerator/Transition or to the OITB PHOENIX. It is the intention of the consortium that the collaboration continues beyond the project to ensure a successful implementation of the results