Astra's Lynparza Boosts Survival in Ovarian Cancer Patients

(Bloomberg) -- Ovarian cancer patients gain an estimated three years before their tumors worsen when they take Lynparza, a drug from AstraZeneca Plc and Merck & Co., according to a study that doctors said will transform how women are treated when they’re first diagnosed.

The risk that patients would die or their cancers would progress was 70 percent lower among those who got Lynparza than in a group receiving only standard therapy, according to the study. The results may prompt doctors to begin adding Lynparza to the first round of treatment for patients who have mutations in cancer-related genes called BRCA1 and BRCA2.

The findings are a positive sign for treatment of ovarian cancer, which will strike about 300,000 women worldwide this year, and position Lynparza far ahead of competitors. More than half of women who receive standard treatment -- surgery to remove diseased tissue and chemotherapy -- relapse within three years.

“There’s a real hope that this treatment will perhaps lead to an increase in the cure rate,” said Jonathan Ledermann, clinical director of the UCL Cancer Institute in London. “There’s no doubt that this is a big step forward.”

Future Blockbuster

The median time to tumor worsening or death in the standard treatment group was 13.8 months, according to findings presented Sunday at the European Society of Medical Oncology Congress in Munich. In the Lynparza group, that median point hadn’t been reached yet -- about 60 percent of the women hadn’t had their tumors get worse at the three-year mark.

The results, also published in the New England Journal of Medicine, are another milestone for Lynparza, projected to sell almost $600 million this year for Astra and become a $1 billion seller by 2020. Merck gained some of the rights to the drug last year in a co-development deal called an externalization agreement.

Lynparza is already approved in breast cancer as well as for patients who have relapsed after their first round of ovarian cancer treatment. The drug, called a PARP inhibitor, blocks a mechanism tumor cells use to repair their DNA, inhibiting or halting growth.

Other companies are developing PARP inhibitors with an eye to expanding in ovarian cancer treatment. Tesaro Inc.’s Zejula is approved for use in recurrent ovarian cancer, and the company has said it expects results for its drug in first-line ovarian cancer by the end of next year.

Pfizer Inc. oncology chief Andy Schmeltz said the company is testing its drug, talazoparib, plus chemotherapy for previously untreated advanced ovarian cancer. The company is also studying the drug in combination with its immune oncology therapy Bavencio. While the U.S. pharma giant may lag some of its rivals, it will still have an important role to play in treatment of the stubborn cancer, he said.

Some of the women in the Lynparza study were upset that the study called for stopping the drug at the end of two years, said Kathleen Moore, a professor of gynecologic oncology and a director at the University of Oklahoma’s Stephenson Cancer Center. However, ongoing data suggest that longer treatment wasn’t needed to prevent cancer from recurring, said Moore, who was the trial’s lead investigator.

“I really feel like we’ve provided convincing data that we don’t have to treat indefinitely,” Moore said. “I feel much more comfortable stopping at two years now. And I wonder if maybe we could have stopped earlier.”

The results represent the most significant improvement in progression-free survival for newly diagnosed cancer patients in recent history, said Dave Fredrickson, Astra’s global head of oncology.

“Ovarian cancer hasn’t seen so many new options in the recent decades,” said Solange Peters, head of medical oncology at University Hospital of Lausanne in Switzerland, who wasn’t involved in the study. “It’s really something which will completely change the way we treat ovarian cancer.”

©2018 Bloomberg L.P.