Tesaro Inc said its experimental ovarian cancer drug niraparib met the main goal of prolonging survival in patients, without the disease worsening, in a late-stage trial, sending its shares to a record high.

The Waltham, Massachusetts-based company's shares more than doubled to $77.

About 22,000 women are diagnosed with ovarian cancer in the United States every year, and nearly 80 percent are diagnosed after it has progressed to a severe stage.

The trial which enrolled more than 500 patients, included subjects some of whom had a BRCA gene mutation. BRCA is a tumor suppressing gene, and ovarian cancer patients who carry this mutation are more treatable as they respond better to chemotherapy.

Analysts said the data increased the probability of niraparib being used as a first-line treatment for ovarian cancer and BRCA-related breast cancer.

"The data was even better than our bullish expectations," Mizuho Securities analyst Eric Criscuolo said.

The results had a positive read-through to Clovis Oncology Inc, which is developing a similar drug. Clovis shares were up 19 percent in morning trading.

Shares of Myriad Genetics Inc also rose 7.3 percent. The diagnostic company makes a test, which was used to recruit patients into Tesaro's trial.

In patients with BRCA mutation, progression-free survival for those treated with niraparib was 21 months, compared to 5.5 months for those on a placebo.

In patients without the BRCA mutation, who are relatively more difficult to treat, the progression free survival was 9.3 months compared to 3.9 months, for those on placebo.