. "alty Tier,??? which reported that of the $54.4 billion spent on prescription drugs in 2007, $5.6 billion went to specialty drugs, generally meaning those used to treat autoimmune disorders, cancer and chronic viral infections such as HIV and hepatitis C.Of that $5.6 billion, Medicare beneficiaries who received low-income subsidies accounted for $4 billion, or 70% of the total." . . . . . . . .