Original sentence: His most controversial political stance is that he is an AIDS dissident; he maintains that the common belief that HIV causes AIDS has not been backed up by sufficient scientific research, yet for political/commercial reasons further research questioning this belief is suppressed.In public he is very outspoken about this point
Edited sentence: His most controversial political stance is that he is an AIDS dissident; he believes that HIV does not cause AIDS, and in public he is very outspoken about this point