Keytruda offers new hope for lung cancer patients

LOS ANGELES (KABC) -- Researchers call the drug Keytruda a new and exciting option in treating the leading cause of cancer deaths worldwide.

One local lung cancer patient experienced what doctors describe as an astonishing recovery.

A few years ago, 61-year-old Cary Parton's only health complaint was nagging back pain. His wife brought him to the emergency room. After a CT scan, doctors discovered tumors on his spine, but the news got worse.

"Well, we hate to tell you this Mr. Parton but you have cancer throughout your body," Parton recalled.

Parton had been a smoker. Doctors diagnosed him with non-small cell lung cancer, the type involved in about 85 percent of cases. But, after chemo and radiation, the tumors got even bigger.

That's when Dr. Edward Garon enrolled him in a clinical trial involving an immunotherapy drug called Keytruda.

"In many patients, it has proven to be a very effective option," said Garon.

Some cancer cells are marked with proteins that make them invisible to the immune system. Keytruda targets these proteins and blows their cover.

"What the cell is doing is using a camouflage," said Garon. "It is masquerading as a normal cell when in fact it is a cancer cell and is something that is damaging to the body."

The drug, which is already in use to treat melanoma, arms the patient's immune system to attack the cancer. Findings from the trial show side effects were better tolerated than chemotherapy.

"I have a bit of a dry mouth right now, and that's probably the biggest reaction," said Parton.

According to the Federal Drug Administration, trials show that tumors shrank in 41 percent of patients treated with Keytruda. The effect lasted between two to nine months.

Now, nearly three years later, Parton continues to get regular infusions.

"I'm about 95 percent reduction in the size of the tumors," said Parton.

"I think that we are starting to see that immunotherapy is a pillar of cancer care, and that has happened quite quickly," said Garon.

Parton feels like he's gone from being on the verge of death to someone who feels healthy and active.

"It's a journey I wouldn't want anybody else to go through, but in my case it's made me hopefully a better person," said Parton.

Doctors say Parton may reach a point where he doesn't need Keytruda anymore or his lung cancer may be managed as a chronic disease.

The next step for researchers is to find out how it may be used in other types of cancer.