Drug developer Zosano Pharma Corp said a mid-stage study testing its experimental patch to treat low blood sugar met the main goal.

The company said the patch, ZP-Glucagon, normalized blood sugar in all the patients who received it.

ZP-Glucagon is the lead treatment that Zosano is developing. The company is also developing a therapy for osteoporosis in early studies.

The company said on Tuesday the study compared ZP-Glucagon to an intramuscular injection that is meant to reverse low-blood sugar in patients who are given insulin to treat Type 1 diabetes.

Zosano said the patch was well-tolerated.

Up to Monday's close, the Fremont, California-based company's shares had lost about 75 percent of their value since they went public on Jan. 27.