The United States launched the largest clinical trial of its kind Monday aimed at studying targeted therapies for cancer based on the genetic traits of tumors, a field known as precision medicine.

The U.S. National Cancer Institute plans to enroll about 1,000 patients beginning in July, experts said at the American Society of Clinical Oncology meeting in Chicago.

South Korea on Tuesday reported its first deaths from the MERS virus, following the largest outbreak outside the Middle East that has infected 25 people and triggered widespread public alarm.

A 58-year-old woman died of acute respiratory failure on Monday and tests later came back positive for MERS (Middle East Respiratory Syndrome), the health ministry said. 

Immunotherapy, which harnesses the power of the immune system in order to attack cancer, is more potent against melanoma when two agents are combined, but side effects rise too, researchers said Sunday.

Findings of a randomized phase III trial compared nivolumab (Opdivo) alone or in combination with ipilimumab (Yervoy) and found the pair was "significantly more effective than ipilimumab alone," according to the results presented at the American Society of Clinical Oncology conference in Chicago.

Modern medicine has made huge strides when it comes to treating children with cancer, and four times as many youths now survive cancer compared to decades ago, researchers said Sunday.

Life expectancy after a battle with pediatric cancer is also longer than it used to be, according to the findings released at the American Society of Clinical Oncology (ASCO) annual meeting.

China is searching for 13 people who came into contact with the first person to enter the country with the MERS virus, health officials said, adding that 64 had already been quarantined.

Eleven people who traveled on a bus with a 44-year-old man from South Korea who entered China with the disease are among the 13 that are being sought, health officials in the southern province of Guangdong said.

China's capital Monday began imposing the country's toughest ban on indoor smoking in hopes of stemming a looming health crisis.

Smoking in Beijing is now prohibited in all indoor public places, including offices, shopping malls and airports. Beijing's main terminal will close its three smoking rooms and special smoking areas will be set up at the city's 600 bus stops.

Worldwide, people who are diagnosed with melanoma are urged to have any lymph nodes that test positive for cancer removed, but researchers said Saturday the operation doesn't necessarily help patients live longer.

Instead, many patients with advanced skin cancer that has just begun to spread to the lymph nodes nearest to the skin tumor could have the tumor removed but likely skip the additional surgery, known as complete lymph node dissection, according to the results of the randomized study released at the American Society of Clinical Oncology (ASCO) annual conference in Chicago.

A federal appeals court has ruled that drug manufacturer Actavis PLC's attempted switch of patented Alzheimer's medication, which halted distribution of the old drug before its patent expires this summer, violates U.S. antitrust law.

The decision unsealed this week explains the ruling last week by a three-judge panel of the 2nd U.S. Circuit Court of Appeals that requires the Irish company to keep distributing Namenda until 30 days after its patent expires on July 11.

For the first time, a major study shows that a drug targeting the body's disease-fighting immune system may improve survival for the most common form of lung cancer.

These newer kinds of drugs have transformed treatment of melanoma, the deadliest kind of skin cancer. Studies presented at a conference Friday suggest these "immune therapies" can play a broader role in more common cancers, including lung, liver, colon and head and neck.

Congolese expert Jean-Jacques Muyembe may be little known to the public, but he has been one of the world's top Ebola investigators since the first epidemic erupted in central Africa in 1976.

Now, amid a decline in a west African outbreak that has taken more than 11,000 lives, Muyembe warns that Ebola will strike again in the future and that the deadly virus poses "a threat to the whole world".