The application is directed to TGF analogs/derepressors that bind to and neutralize cystine knot-containing BMP antagonists--such as the CAN subfamily of Cystine-knot proteins including sclerostin. The subject TGF derepressors can be prepared as substantially pyrogen-free pharmaceutical compositions for administration to mammals, in treating diseases such as bone diseases including osteoporosis, and any conditions with lesser-than-desired amount of BMP activity.