From: https://en.wikipedia.org/wiki/Rabies

As of 2016, only fourteen people were documented to have survived a rabies infection after showing symptoms. However, research conducted in 2010 among a population of people in Perú with a self-reported history of one or more bites from vampire bats (commonly infected with rabies), found that out of 73 individuals reporting previous bat bites, 7 people had rabies virus-neutralizing antibodies (rVNA). Since only one member of this group reported prior vaccination for rabies, the findings of the research suggest previously undocumented cases of infection and viral replication followed by an abortive infection. This could indicate that in rare cases people may have an exposure to the virus without treatment and develop natural antibodies as a result.

At least two treatment schemes have been proposed for treating rabies after the onset of symptoms, the Milwaukee Protocol and the Recife Protocol. The Milwaukee Protocol was first used in 2004 on Jeanna Giese, who became the first person known to have survived rabies without preventive treatments before symptom onset. The protocol puts a person into a chemically induced coma and uses antiviral medications to prevent fatal dysautonomia. The overall protocol is complex; the sixth version of the protocol last updated in 2018 consists of 17 pages with 22 steps of treatment, detailed monitoring, and a timeline of expected complications. The Recife Protocol follows the same principle but differs in details like termination of sedation and supplementary medication.