Ramatroban as a Novel Immunotherapy for COVID-19

Area of Science:

• Immunology
• Virology
• Pharmacology

Background:

• SARS-CoV-2 infection impairs innate and adaptive immunity, leading to severe disease, particularly in older adults.
• Respiratory viruses, including SARS-CoV-2, induce cyclooxygenase-2 (COX-2) to produce prostanoids like Prostaglandin D2 (PGD2) and thromboxane A2.
• Airway PGD2 levels rise with age, and PGD2 signaling via DP2 receptors suppresses crucial immune responses (interferon-λ production and myeloid monocyte-derived suppressor cell activity).

Purpose of the Study:

• To investigate the potential of Ramatroban, a dual DP2 and TP receptor antagonist, as a therapeutic agent for COVID-19.
• To explore Ramatroban's ability to reverse SARS-CoV-2-induced immune suppression and prothrombotic states.

Main Methods:

• The study reviews existing literature on SARS-CoV-2 pathogenesis, prostanoid pathways, and Ramatroban's known pharmacological actions.
• It analyzes the molecular mechanisms by which PGD2 and thromboxane A2 contribute to COVID-19 severity.
• It evaluates Ramatroban's efficacy in preclinical models and its clinical safety profile from allergic rhinitis treatment.

Main Results:

• Ramatroban demonstrated the potential to reverse PGD2-mediated immunosuppression and thromboxane A2-induced prothrombotic effects.
• These reversed processes mirror key pathological mechanisms observed in SARS-CoV-2 infection.
• Ramatroban has a well-established safety profile from its use in treating allergic rhinitis.

Conclusions:

• Ramatroban's dual antagonism of DP2 and TP receptors offers a promising therapeutic strategy against SARS-CoV-2.
• It may counteract critical aspects of COVID-19 pathogenesis, including immune suppression and thrombosis.
• Ramatroban warrants further investigation as a novel immunotherapy for COVID-19.