Carrageenans as Broad-Spectrum Microbicides: Current Status and Challenges

Area of Science:

• Marine biotechnology
• Natural product chemistry
• Antimicrobial drug discovery

Background:

• Red algae yield diverse carbohydrates, notably sulfated polysaccharides with antimicrobial properties.
• Carrageenans (CGs) demonstrated significant antiviral potency and safety in preclinical studies, positioning them as potential microbicides.
• Clinical trials failed to validate CGs' anticipated benefits, necessitating a re-evaluation of their development.

Purpose of the Study:

• To comprehensively review preclinical and clinical data of carrageenan-based microbicides.
• To assess the potential for a second pharmacologic development attempt of CGs as preventive microbicides.
• To identify future research directions for successful CG-based antimicrobial prophylactic development.

Main Methods:

• Summarized in vitro toxicities and in vivo safety profiles of CGs.
• Compiled in vitro, ex vivo, and in vivo antiviral activities against a range of viruses.
• Described antiviral mechanisms of action and the development of antiviral resistance.

Main Results:

• CGs exhibit broad-spectrum antiviral activities against viruses including HIV, herpesviruses, and respiratory viruses.
• Preclinical data indicate favorable safety profiles, but clinical efficacy remains unproven.
• Understanding of CGs' antiviral modes of action and resistance development is crucial.

Conclusions:

• Carrageenans possess promising antiviral properties, but clinical translation challenges persist.
• A thorough re-evaluation of CG development is essential for future research.
• Further investigation into CGs' strengths and weaknesses can guide the development of effective antimicrobial prophylactics.