I wouldn't look for anything new in the way of FDA approved drugs pretty much ever again. Propecia wasn't a "blockbuster" for Merck by any stretch, and the costs of getting drugs approved are tremendous. The word on the street is that Glaxo Smith Kline cancelled the trials of Avodart (dutasteride, a 5ar-inhibitor) because it wouldn't be profitable given that its not all that different or better than propecis.
Smaller companies continue to develop new treatments, but they often don't have the solid scientific backing of the current "proven" treatments. This doesn't necessarily mean that they don't work, just that less is known about how well they work, which makes them more of a risk to rely on to save your hair. Most of the new stuff these smaller companies come up with is in the form of topicals, either anti-infflamatories, growth stimulants, DHT blockers/inhibitors, or combinations of all 3.
The more recent and exciting developments have been in tissue engineering to replace hair (hair multiplication) rather than medical treatments. The beauty of hair multiplication, should it ever come to be, is that it should be a one-off permanent treatment, that gets you back all of your lost hair.
