The Free Filep Karma Campaign says Indonesia must adhere to international obligations on the treatment of prisoners by addressing the Papuan political prisoner's medical needs.
Mr Karma, who is serving a 15-year jail term in Jayapura for raising the banned Papuan Morning Star flag, has been seriously ill but officials have refused to pay for his treatment.
The UN Working Group on Arbitrary Detention recently declared Mr Karma's detention illegal under international law.
A human rights lawyer who works with the Campaign, Melinda Janki, says she understands the prisoner's need for treatment is urgent.
"But even if it wasn't urgent, the fact is that the state of Indonesia has a legal obligation to give him proper medical treatment because he is in prison and there are UN standards for the minimum treatment of prisoners."
Melinda Janki of the Free Filep Karma Campaign