PARIS (AP) — Drugmaker Sanofi is abandoning two drugs in the late stages of development after trials revealed they weren't more effective than other therapies.

One drug, iniparib, was given to lung cancer patients in combination with chemotherapy and compared to treatments of chemotherapy alone. The company said Monday iniparib did not improve the patients' survival rate.

Another, the blood thinner otamizaben, was tested against a combination of heparin and eptifibatide, both of which prevent blood clots. It did not prove more effective than those therapies.

The failures of these studies are a blow to Sanofi, which is struggling to develop new drugs after patents on several of its blockbuster drugs expired. It was especially hard hit the loss last year of the patent for Plavix, which was the world's second best-selling drug.