Treating urge to prevent crime
The project is grounded on the principle that sexual attraction to children is a medical problem, and as Beier said, "not a crime" until the urge is acted upon.
The World Health Organization too classifies paedophilia as a "sexual preference disorder".
Over one or two years, during two-hour sessions every week, the patient is taught to develop strategies to stop himself from acting on his tendencies or from consuming child pornography.
The programme also helps the patient to acquire a level of empathy towards potential victims, which could go towards dissuading him from hurting them.
The patient can choose to remain anonymous throughout the treatment, even with his therapist, and at the end of the programme, he can request follow-ups.
Medical help, such as chemical castration, is also offered on a voluntary basis.
Scientists from around the world including countries in North America as well as Switzerland and India, have been watching the project with interest.
"In France, we are still at the starting point on creating a programme that is similar to Germany's," said a psychiatrist at France's health and medical research institute Inserm, Serge Stoleru.
He said the response from authorities had been that "paedophilia is a tricky subject."
But even in Germany, one of the countries scarred by a massive paedophile priest scandal in the Roman Catholic Church, the therapy programme is controversial.
Not only is there strong societal pressure against the programme, Beier said that even in the pharmaceutical world, there is "great reticence" towards developing medicine for paedophiles that could take effect rapidly.
However, Jerome Braun, who leads a child protection foundation called Hansel and Gretel that co-funds the therapy programme, said that prevention work must not only be targeted at bringing awareness to potential victims in kindergartens or schools.
"It should also look at potential criminals because each act prevented is a child saved," he said.