hydroxychloroquine + camostat mesylate

Hydroxychloroquine + camostat mesylate is an experimental combination therapy investigated primarily for the treatment of COVID-19. Hydroxychloroquine is a small molecule antimalarial and immunomodulatory agent that inhibits endosomal acidification, thereby interfering with viral entry and replication. Camostat mesylate is a serine protease inhibitor that blocks the activity of transmembrane protease serine 2 (TMPRSS2), which primes the spike protein of SARS-CoV-2, facilitating viral entry into host cells. The rationale for combining these drugs stems from their complementary mechanisms—hydroxychloroquine targets endosomal pathways while camostat inhibits TMPRSS2-mediated cell surface entry—potentially resulting in synergistic antiviral effects against coronaviruses[1][2][4]. This combination has been evaluated in preclinical studies and clinical trials for COVID-19 but has not received regulatory approval as a fixed-dose product.