Diagnosed 10 months ago with advanced colon cancer, the Pittsboro woman, 63, has been improving since she started taking tumor-fighting drugs that are right for her body.

The right dose of the right drug for the right patient at the right time -- that's what personalized medicine promises.

Doctors have long known that no two patients are alike. Now screening tests and drugs are available to tailor treatments to patients' individual needs, including their genetic makeups.

The University of North Carolina is among about 10 institutions taking a lead in the effort. In August, the university established a research institute to tap into medical, public health, health economics and drug development expertise on its campus and elsewhere.

The hope is that work done at the Institute of Pharmacogenomics and Individualized Therapy, the institute's unwieldy name, can alleviate the bottlenecks that have made personalized medicine an exception, rather than standard therapy.

Researchers and doctors at the institute say there is more to learn about the complex underpinnings of many diseases. Insurers must be persuaded that such testing is worthwhile, and doctors must be educated about testing so they can prescribe treatments accordingly, they say.

"The more examples we have, the easier it will be to bring more customized therapy into common usage," said Myla Lai-Goldman, chief scientific officer and medical director at LabCorp in Burlington, which is working with the institute. LabCorp offers about 30 genetic screening tests to tailor drug treatment.

Progress is being made, they say, but slowly.

Recent developments have aided their cause. The mapping of the human genome in 2003 opened the door for researchers to delve much more deeply into the relationship between patients' genes and diseases.

Increased regulatory scrutiny of drug safety in the past two years has prompted drug makers to try harder to make sure new drugs are prescribed only to patients who won't suffer serious side effects. However, existing tools are crude, there aren't nearly enough of them and their use is not widespread.

It took three tries before Bert O'Neil, an oncologist at UNC Hospitals in Chapel Hill, found the two-drug combination that shrank the stubborn cancer that had spread from Distasio's colon to her liver.

"It would have been nice if we had gotten here right away instead of taking all the steps we took," O'Neil said. "That's where we're still operating in the Stone Ages."

HIV lessons

Cancer is one of the few areas that is seeing the push toward more personalized medicine. That work, still in its infancy, is using the lessons learned from AIDS research.

Personalized medicine took shape in the past decade as the fight against HIV, the virus that causes AIDS, intensified.

HIV quickly grows resistant to drugs and causes symptoms that can differ from patient to patient. To corral the virus, doctors rely on a blood test that provides a fingerprint of each patient's HIV. The information influences which drugs a doctor prescribes for the patient's cocktail.

The model is being copied in the fight against cancer.

About a dozen targeted cancer drugs have been approved since 1998, but only three are dramatically better than conventional treatments.

Colon cancer is notoriously difficult to treat, which limits drug options.

Like about 80 percent of all colon cancer patients, Distasio started on the standard drug combination for patients whose cancer has spread. Surgeons had removed the cancerous part of her colon. To shrink the tumor in her liver, she took a generic chemotherapy drug, another drug to help it work better and a third that was designed to interrupt the blood flow to the tumor.

The combination didn't work.

Then she tried a chemotherapy drug that was still being studied. To qualify for the study, Distasio had to undergo a genetic test, because the drug can lead to serious infections in about 10 percent of patients who have a particular genetic makeup.

That drug didn't work.

Finally, O'Neil mixed the drug cocktail that shrank the tumor in Distasio's liver: a targeted chemotherapy for colon cancer and a drug that interferes with the growth of tumor cells.

Both drugs can cause serious side effects, including severe diarrhea and skin problems.

The skin on Distasio's fingertips is cracking, and a rash covers her chin. But she said she's happy about O'Neil's winning drug cocktail.

"I was beginning to think he only knew the word 'No,' " Distasio said.

Good fortune, hunches

Lacking tests to check which drugs Distasio was most likely to respond to, O'Neil relied on the standard alternative to the generic chemotherapy Distasio had taken -- and a hunch.

For doctors to have to rely on hunches and trial and error isn't good enough, said Howard McLeod, director of UNC's pharmacogenomics institute.

"Based on the current therapy, you're dependent on good fortune," McLeod said. "We have to be smarter."

Initiatives are under way to prolong the lives and improve the qualify of life of patients suffering from cancer and other diseases. But McLeod projected that it will be at least 20 years before tests are used to personalize the drug treatment of about half of all patients.