EDITORIALS Disease insights hold promise
New insights into the underlying cause of some life-threatening ailments have opened doorways to novel forms of treatment, and could lead to breakthroughs in the near future. The first of these insights concerns the role of inflammation. It has long been known that some diseases, among them asthma, irritable-bowel syndrome and Crohn’s disease, are caused, in part, by chronic inflammation.
But over the past few years, it has become evident these maladies are merely the tip of an iceberg.
It appears that a significant number of heart attacks and certain cancers are also due to chronic inflammation. This points the way to a deeper understanding of these ailments, and potentially, to radically new kinds of therapy.
A four-year research project that concluded last year followed 10,000 heart-attack victims. The study found that treating these patients with anti-inflammatory drugs reduced repeat attacks by 24 per cent.
More strikingly, and unexpectedly, among patients given the highest doses, cancer deaths fell 51 per cent. Experts in the field say this study has ushered in “a new era of therapeutics.”
The second insight has to do with the mechanisms that give rise to genetic disorders.
Last year, researchers in Britain announced they had decoded the toxic substance that causes Alzheimer’s disease. To date, the drugs that are available merely slow the onset of symptoms, and even then, only to a modest degree.
But now that the genetic malfunction that causes Alzheimer’s is better understood, the way is open for computer modelling to identify new treatments that might halt damage to the brain.
Similar intuitions about the workings of ALS (Lou Gehrig’s disease) have led the U.S. Food and Drug Administration to approve the first new drug for this disorder in more than two decades. Tests showed the medication slowed the loss of physical function by 33 per cent.
A new form of gene therapy has produced dramatic results in a year-long clinical trial of patients with type A hemophilia. (There are two types — A and B — of which the former is more common.) The disease, usually hereditary, causes internal bleeding as the clotting process is disrupted.
There were only nine participants in the trial — too few to draw lasting conclusions. But in six of the seven patients who received the highest dose, bleeding stopped entirely.
Last, several clinical trials are underway in patients with melanoma, a potentially fatal skin cancer. The trials were made possible by a better understanding of the genetic structure of this tumour.
In the past, cancers were primarily treated with surgery, chemotherapy and radiation. But these are blunt tools, in particular chemotherapy, which simply targets any cell that divides more rapidly than usual. That’s why recipients lose their hair — hair cells subdivide more quickly than other cells.
The newest cancer treatments are much more precisely focused. Rather than attack the entire cell, they attach signalling mechanisms to its surface that eliminate the cell’s ability to divide unchecked.
Caution is needed here. The history of medicine has seen its share of disappointments; drugs that looked promising at first, but ultimately failed; novel procedures that caused intolerable side-effects. There are no guarantees.
But what does give cause for hope is the emergence of fundamental new insights into the mechanisms of disease.
In the past, medical science often proceeded from cure to cause. Drugs were found that helped, but no one could say why. That process is being reversed.
Instead, as we see further into the causes of ill health, cures are beginning to reveal themselves. How far these gains will advance in 2018 is unclear. But it does seem that we are on the verge of genuine progress.