* Nexavar improves progression-free survival
* Bayer to apply for marketing approval in coming months
* To present analysis of study at medical conference (Adds details, share price, background)
FRANKFURT, Jan 3 German drugmaker Bayer said its cancer treatment Nexavar reached a goal of improving the survival of patients with a certain type of thyroid cancer in a late-stage clinical trial.
The company said on Thursday it planned to submit data from the trial in the coming months in a bid to win regulatory approval to sell Nexavar as a treatment for radioactive iodine (RAI) refractory differentiated thyroid cancer.
It would present a detailed analysis of the study, in which 417 patients took part, at an upcoming medical meeting, it added, without providing details.
Shares in Bayer were 0.3 percent higher at 72.18 euros by 1149 GMT, outperforming a 0.3 percent decline by Germany's blue-chip DAX index.
Nexavar, developed jointly with Onyx Pharmaceuticals , is already approved to treat liver and kidney cancer in more than a 100 countries, with peak sales seen at 750 million euros ($993 million) a year.
The drug, which made 725 million euros of sales in 2011, missed its goal in a trial with lung cancer patients last year.
There are more than 160,000 new cases of thyroid cancer each year, and about three times as many women are diagnosed with it as men, making it the sixth most common cancer in women, according to Bayer.
RAI-refractory thyroid cancer is more difficult to treat than most types and has a lower survival rate.
($1 = 0.7553 euros) (Reporting by Maria Sheahan and Frank Siebelt; Editing by Mark Potter)