The Smart-Pill Solution

[gdpawel]

Monoclonal antibodies like Herceptin, are large molecules that attach to specific proteins on the outside of cancer cells and do not have a convenient way of getting access to a large majority of the targeted cells on the inside, which are protected from the drug. Plus, there is multicellular resistance, the drugs affecting only the cells on the outside may not kill these cells if they are in contact with cells on the inside. The cells may pass small molecules back and forth. This would be a very good reason Tykerb, a small molecule drug, may be much better than Herceptin.

However, each of these new targeted drugs are not for everybody (just as conventional cancer drugs are not for everybody). Even when the disease is the same type, different patients' tumors respond differently to the same agents. As the saying goes, "don't throw out the baby with the bath water." If a drug works extremely well for a certain percentage of cancer patients, identify which ones. If one drug or another is working for "some" people (not average populations), then obviously there are others out there who would also benefit.

The study of cell function analysis tells us that even when the disease is the same type, different patients' tumor respond differently to the same agents. Herceptin (or any other large molecule targeted drug) may be more beneficial to some patients than Tykerb, Sutent, or any other small molecule targeted drug.

Whatever the percentage of patients benefit from these drugs, the point is, "targeted drugs are not for everybody." Pre-tests can help identify the individual cancer patient the drug works extremely well for, or it can tell that the drug is resistant. This could be Tykerb, Tarceva, Iressa, Sutent or Nexavar, because of being small molecule drugs. It is important to "personalize" cancer treatment, and this can be accomplished by "testing the tumor first."

There are huge economic problems here. Pharma cannot make drugs unless they can realize a profit. The ordinary trial system will not suffice if we are to encourage new drugs for restricted numbers of patients. More and more physicians and patients are turning to individualized therapies to treat cancers. Without individualized testing the efficacy of these drugs, it's difficult to determine which drugs are best for patients who don't respond to standard therapies.