On Monday, two big pharmaceutical companies delivered some good news about one of their projects. Merck (NYSE:MRK) and AstraZeneca (NASDAQ:AZN) announced in separate press releases that their cancer drug Lynparza received approval by Japan's pharmaceutical regulator for the treatment of three types of the disease: prostate, ovarian, and pancreatic.

The country's Ministry of Health, Labor, and Welfare approved Lynparza as a maintenance treatment following the administration of first-line chemotherapy in patients with certain types of those cancers.

Cancer attacking an organism.

Image source: Getty Images.

"For patients in Japan diagnosed with each of these types of cancer, there are very few treatment options," the companies quoted Merck Research Laboratories' head of global clinical development, Roy Baynes, as saying.

"Approvals for treatments such as Lynparza, the first PARP inhibitor to be approved in these specific types of metastatic castration-resistant prostate cancer and metastatic pancreatic cancer in Japan, enable us to advance this evolving era of personalized medicine and change how these cancers are treated," he added.

According to the two companies, this year nearly 11,000 women in Japan received a diagnosis of ovarian cancer. Over the course of 2020, more than 5,000 died from it. Meanwhile, there were over 100,000 new cases of prostate cancer in the country during the year, and roughly 44,000 new cases of pancreatic cancer.

This is the latest green light for Merck and AstraZeneca's drug, which won its first major approvals in 2014 from the U.S. Food and Drug Administration (FDA) and the European Union's European Medicines Agency (EMA).

Both stocks closed higher on the news, although Merck's 0.4% gain trailed the 0.9% rise of the S&P 500 index. AstraZeneca shares increased by 1.8% on the day.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.