The case in Hamm, Hamburg, was detected by insurer AOK when officials questioned the amount being paid out for drugs.

The men, named by authorities as Ronald N., 45, and Frank F., 51, worked with pharmacist Wilhelm S., to fill repeat prescriptions for expensive HIV drugs costing up to €1,300 a time.

Their doctor was reportedly innocent of any collusion, believing the men when they told him they had lost prescriptions, or had had them stolen.

Wilhelm S. filled only some of the prescriptions, but charged the AOK for all of those written, and shared in the profits with the two patients.

It is thought such fraud, while not often on such a spectacular scale, are often perpetrated throughout Germany.

Hermann Bärenfänger, spokesman for the Techniker Krankenkasse insurer told the Hamburger Abendblatt, “There is a real black market for health insurance cards, which you can clearly see at some train stations.”

He said the efforts of investigators at the TK hindered around €30 million worth of fraud last year – and this at an insurer which represents around 10 percent of the German market.