AstraZeneca's new ovarian cancer drug has been approved by the U.S. FDA, following approval by the European Commission. AstraZeneca foresees sales of around $2 billion per annum from this drug, according to a Reuters report.

Competition for ovarian cancer drugs includes Roche AG's Avastin drug for patients with recurring ovarian cancer, which was approved in November, and a new drug from Amgen which is in the trial stage.

The new cancer drug Lynparza belongs to a class of drugs called poly ADP-ribose polymerase (PARP) inhibitors. The drug is for women who have advanced ovarian cancer associated with defective BRCA genes.

"Today's approval constitutes the first of a new class of drugs for treating ovarian cancer," Dr Richard Pazdur, a director at the FDA's Center for Drug Evaluation and Research, said in a press release.

Approval of the AstraZeneca cancer drug follows a clinical trial of 140 women suffering from BRCA mutation-associated ovarian cancer. Thirty-four percent of patients experienced partial shrinkage or complete disappearance of their tumors for an average of eight months, according to FDA reports.

The cancer treatment drug Lynparza has a number of side effects, including nausea, fatigue, vomiting, diarrhea, headache, decreased appetite, and joint and muscle pain. Serious side effects include lung inflammation and a condition where the bone marrow is unable to produce enough blood.

Women must undergo a genetic test to confirm that they have BRCA gene mutations before they can be treated with the new ovarian cancer drug. The FDA approved the test at the same time as the drug. Women with defective BRCA genes have an increased risk for ovarian and breast cancer. Normally, the BRCA gene repairs genetic material and suppresses tumor growth. When the gene is mutated it cannot function. It is believed that 10 to 15 percent of all ovarian cancer is associated with these mutations, according to the FDA.

In 2014, nearly 22,000 American women were diagnosed with ovarian cancer, according to reports and more than half will eventually die from the disease.