What's the difference between imiquimod and topical human interferon alpha-2beta? can it be more beneficial to apply both concurrently?

Neither: surgical removal is the gold standard. There's not great data on wart viral infection if it isn't visible. If there are visible warts, surgery is the best treatment and there's no data that interferon helps at all, and slight data that Imiquimod lowers recurrence rate after surgery. There's not much data out there for a role for interferon except maybe in respiratory warts.