Original medicare does not cover prescriptions. They are covered under medicare part D. Medicare advantage plans generally include Medicare part D. They cover biologics but at the worst rate. Generally you will go in to the u201cdonut holeu201d in the first month and depending on the drug may come out of the u201cdonut holeu201d that same month or the next month or two. Now here comes the trick. Since the co-pay is so high, most retired people cannot afford the drugs even with insurance and co-pay assistance is not automatic for people on medicare or medicaid but you can apply for assistance. You have to show evidence that you cannot afford the drugs and you do have Medicare part D or an advantage plan with a drug benefit. The drug company will collect directly from the government the money that they would pay for your prescription and by mailing the drug directly to you, keep the pharmacyu2019s part of your drug cost for themselves. They actually keep more for themselves than what they would get if they refused to help with your co-pay.