I don't know of any scientific evidence that azelaic acid works as a 5a-reductase inhibitor, other than one single in vitro study. I've never seen even a single study that tested it topically on living animals, whether they be rats, mice, hamsters, stumptailed macaques, humans, or anything else. I tend to doubt that it works to suppress DHT when applied topically. I think your good results were probably just from the minoxidil.