Shares of Omeros Corporation (OMER) closed the day up 72% after the company announced positive phase 2 results in patients with thrombotic microangiopathies -- TMAs. These TMAs occur when a blockage of small blood vessels -- known as capillaries -- become blocked in vital organs such as the brain and kidney. 

When this blockage occurs red blood cells can't travel through the brain/kidney and form traffic flow problems -- clots. That is why this TMA disease is a rare life-threatening disorder that can possibly lead to death. In addition to enrolling patients with TMA, the trial also enrolled patients with atypical hemolytic Uremic Syndrome -- TMA occurring more often.

The phase 2 results were positive as observed with some patients in the clinical trial. For instance two patients in the mid dosage cohort saw a platelet count improvement of 48%. In addition one patient in the high dose cohort saw a 68% improvement in the platelet count. This is huge because pateints with TMA and aHUS have low platelet counts and are not able to transfer red blood cells as easily. 

Omeros Corporation will now meet with the FDA later this year to possibly discuss a phase 3 trial plan that will allow the company to move forward with this program. Considering these patients don't have many options, this trial didn't compare the company's drug against a placebo compound. Instead in order to determine efficacy, the company evaluated a mean change from baseline for these patients. This is how positive efficacy was determined for this trial and the FDA is on board with this method.