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New Drugs Make Big Difference in Treating Lung, Prostate, Colon Cancers

Doctors are reporting success with newer drugs that control some kinds of cancer better than current medicines. They say these drugs reduce the risk that the cancer will come back and make treatment simpler and easier for patients.

One such drug, taken as a daily pill, called Tagrisso, comes from drug manufacturer AstraZeneca. The British-based company says Tagrisso targets a mutation in the patient's genes, unlike chemotherapy drugs, which can kill both cancerous and healthy cells.

Doctors say the new drug's side effects can be controlled long enough that it can be used for several years to help prevent the cancer from returning.

Yet Tagrisso and other newer drugs can cost $150,000 or more a year. How much patients end up paying depends on their healthcare insurance, earnings, and other considerations.

Lung cancer

Lung cancer kills more than 1.7 million people worldwide each year. Roy Herbst is a doctor with the Yale Cancer Center in the United States. He led a study of Tagrisso in 682 patients with the most common form of the disease. All had operable tumors with a mutation in a gene called EGFR. This unusual genetic structure is found in 10 percent to 35 percent of such cases, mainly among Asians and non-smokers.

About half of the patients were given chemotherapy after their tumor operation. The drug treatment uses powerful chemicals to kill the cancer cells. The patients then took Tagrisso or harmless pills called placebos.

Independent observers stopped the study in April when the effectiveness of Tagrisso seemed clear.

After two years on average, 89 percent of patients taking the drug were alive without cancer returning, compared to 53 percent of those on the placebo. Severe side effects were a little more common on Tagrisso. They included patients feeling tired and reddish skin in the mouth or around the nails.

U.S. health officials have approved Tagrisso for use in treating advanced lung cancer, and "the excitement now is moving this earlier" before the disease has widely spread, noted Herbst.

The drug costs about $15,000 a month.

Prostate cancer

Men with advanced prostate cancer often are treated with medicines to block male hormones that can help the cancer grow. The drugs are injected as shots in the arm every few months but take days or weeks to start working. They can also cause bone pain and other problems.

An experimental drug called relugolix is a different kind of hormone blocker and the first meant for use as a daily pill. The drug is a product of Myovant Sciences. Researchers tested it against shots of the drug leuprolide, an injectable man-made hormone, every three months in 930 men. They were treated for nearly a year.

The company reports that about 97 percent on the experimental drug kept hormones blocked throughout that time, compared to 89 percent on leuprolide. Four days after the start of treatment, 56% of men on relugolix and none on leuprolide had hormones blocked.

Three percent of the men taking relugolix experienced a serious heart problem, such as a heart attack or stroke. That compares to six percent of the men on leuprolide. The difference was even greater among men who suffered heart problems earlier.

Myovant is seeking approval from the U.S. Food and Drug Administration for the drug.

Colon cancer

Merck & Company manufactures Keytruda, an experimental drug, that helps the body's natural defense system find and fight cancer. Keytruda proved better than traditional chemotherapy treatments for people with advanced colon cancer and tumors with gene defects that result in a high number of mutations.

The study involved 307 patients in France. Those given Keytruda went more than 16 months on average before their cancer worsened. That compares with 8 months for those taking chemotherapy treatments. After a year, 55 percent on Keytruda were alive without worsening cancer compared to 37 percent on chemotherapy. After two years, the rate was 48 percent versus nearly 19 percent.

About 22% of people getting Keytruda had severe side effects compared to 66% on chemotherapy.

The Associated Press adds that Keytruda costs about $12,500 a month.

I'm Jonathan Evans.