delanceyplace.com 7/1/13 - the hard business of new medical treatments

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In today's selection -- the hard business of new medical treatments:

"Most new medical treatments and technologies are about a half century in the making. Theodore Friedmann, one of the founders of gene therapy and director of the Gene Therapy Laboratory at the University of California, San Diego, offers two examples. 'The first bone marrow transplant was done in 1957. It took twenty years before the survival rate crept above one percent.' The survival rate improved when immunity-suppressing drugs came on the scene in 1978, and when a dozen years later other drugs became available that boost the number of bone marrow stem cells entering the bloodstream.

"Cancer chemotherapy is Friedmann's second example of a medical technology slow to mature. The first clues that some cancers could even be treated came from post-World War I autopsies that revealed too few white blood cells in people poisoned with mustard gas. Might lowering the white blood cell count help people with leukemia, who make too many such cells? Could a toxin in one situation be an effective treatment in another? In 1948 Sidney Farber, a pathologist at Harvard Medical School, discovered the compounds aminopterin and methotrexate, which became the very first chemotherapies. They were used to treat acute leukemia in children. 'At first the cure rate was very low. By the 1980s it was sixty to seventy percent, and now it is eighty-five to ninety percent. It took three to four decades to tweak the delivery system, refine the drugs, and add radiation. Each decade, the survival rate jumped ten percent. Cancer chemotherapy is the best example of how we learn from problems,' says Friedmann. ...

"In 1796, young James Phipps tended the garden of Edward Jenner, an English physician with an interest in infectious disease. ... James was eight years old when the doctor tried something on him that would become the smallpox vaccine, which ultimately rid the world of this extremely disabling disease. At the time, smallpox killed a third of its victims, and 80 percent of infected children. Painful blisters covered the body and blindness was a frequent complication. Each year, millions died.

"For many years in many parts of the world, people had been inoculated against smallpox. This entailed transferring a scraping from a sufferer's skin lesion to a scratch on a healthy person, which was more likely to produce a mild case than a severe one. It was also well known that dairymaids did not contract smallpox. Jenner, after hearing a milkmaid say, 'I shall never have smallpox for I have had cowpox,' put these facts together to hypothesize that scratching the skin of a healthy person with drippings from the much milder cowpox could protect against smallpox. So he scratched the skin on young James's arm and rubbed into it material from a cowpox pustule found on the hand of a dairymaid, Sarah Nelmes. For a few days afterward, James had only a mild headache, chills, and poor appetite.

James Gillray caricatured recipients of the vaccine developing cow-like appendages.

"James received his first 'vaccination,' consisting of cowpox-carrying pus, on May 14. The test came on July 1, when Jenner rubbed material from a smallpox pustule into a scratch on James's arm. The boy didn't develop smallpox then, or at any of several other times when the doctor repeated the smallpox exposure. Nor did James pass any pox to the two children who slept with him. He lived, in fact, until the then-great age of sixty-six. It's unlikely that James knew he was in an experiment."