What happened Shares of Akebia Therapeutics (NASDAQ: AKBA) were soaring 14.9% higher as of 10:53 a.m. EDT on Tuesday. The biopharmaceutical company announced positive results earlier in the day from two phase 3 clinical studies evaluating vadadustat in treating anemia due to chronic kidney disease (CKD). These studies were conducted by Akebia's commercialization collaboration partner in Japan, Mitsubishi Tanabe Pharma Corporation (MTPC). So what One of the phase 3 clinical studies was conducted on Japanese CKD patients who were on hemodialysis while the other study was conducted on Japanese patients who weren't on dialysis. The good news for Akebia was that in both studies, vadadustat achieved what's called "non-inferiority" compared to darbepoetin alfa, an erythropoiesis stimulating agent (ESA). Non-inferiority simply means that Akebia's drug didn't perform worse from a statistical standpoint than the ESA drug. Image source: Getty Images. Treatment using ESA for CKD patients with anemia has fallen because of the increased cardiovascular risk associated with the drugs. With vadadustat performing as well as a top ESA treatment, Akebia and MTPC should have a great opportunity in Japan. But what about Akebia's prospects in even bigger markets outside of Japan? The company continues to conduct late-stage clinical studies to support a regulatory approval path for vadadustat in the U.S. and Europe. The drug's success in the Japanese studies certainly bodes well for Akebia's chances in those studies. Now what Akebia plans to discuss the phase 3 study results announced today in more detail during its fourth-quarter update on March 18. The company said that its partner, MTPC, expects to file for regulatory approval in Japan later this year. The next big event for Akebia's pipeline should come in the first quarter of 2020, when the company expects to announce results from its U.S. phase 3 clinical study of vadadustat targeting dialysis patients. Results from another U.S. pivotal study for non-dialysis patients are anticipated by mid-2020. 10 stocks we like better than Akebia TherapeuticsWhen investing geniuses David and Tom Gardner have a stock tip, it can pay to listen. After all, the newsletter they have run for over a decade, Motley Fool Stock Advisor, has quadrupled the market.* David and Tom just revealed what they believe are the ten best stocks for investors to buy right now... and Akebia Therapeutics wasn't one of them! That's right -- they think these 10 stocks are even better buys. See the 10 stocks *Stock Advisor returns as of March 1, 2019Keith Speights has no position in any of the stocks mentioned. The Motley Fool has no position in any of the stocks mentioned. The Motley Fool has a disclosure policy.