Shares of Aveo Pharmaceuticals Inc. fell on Jan. 3 as investors were disappointed the drugmaker’s potential treatment for advanced kidney cancer missed expectations, despite faring better than a rival drug in a late-stage study.

Aveo tested the effectiveness and safety of its drug, tivozanib, compared to Bayer’s Nexavar in 517 patients. The company said tivozanib showed a statistically significant improvement in progression-free survival time, with a median of 11.9 months. That compares to a median of 9.1 months for Nexavar, or sorafenib.

Tivozanib showed a statistically significant improvement in progression-free survival in a subpopulation of patients who had no previous cancer treatments. Its median of 12.7 months topped 9.1 months for sorafenib.

Aveo is developing tivozanib with Japanese drugmaker Astellas Pharma Inc. The companies plan to release details of the study in June at the 2012 Annual Meeting of the American Society of Clinical Oncology. They also plan to submit the drug for marketing approval this year to regulators in the United States and Europe after collecting and analyzing all trial data.

The Associated Press