Antiinflammatory activity of alpha-methyl-3-phenyl-7-benzofuranacetic acid (R-803).

The antiinflammatory activity of R-803 (alpha-methyl-3-phenyl-7-benzofuranacetic acid), a new nonsteroidal drug, has been demonstrated. The oral administration of R-803 inhibits carrageenan-induced edema of the rat's paw, ultraviolet-induced erythema of guinea-pig skin, adjuvant-induced and 6-sulfonamidoindazole-induced arthritides of the rat at doses in the range of 1.0 to 6.0 mg/kg. It also inhibits the cotton pellet-induced granuloma in the rat at higher doses.