Drug companies and cancer

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So….where are we now with new therapies that are actually saving lives for people with cancer?  As I have discussed before, have we seen any progress in the last ten years?  We have certainly advanced our knowledge of cancer and signaling pathways and have even come up with new strategies to target cancer.  Let me make a quick list of the things we have learned in the last ten to 15 years…

1.  We have now started looking for mutations in patients with certain kinds of cancer such as advanced melanoma (BRAF mutation V600E) as a means of identifying patients who should respond favorably to drugs that target those mutations.

2. Immunotherapy has potential to work (and does so in rare cases) but still not well against some cancers.   Antibody therapy is used against some cancers such as B cell cancer and even now in skin cancer with some success.  Things that help boost the immune system do show limited efficacy in some cancers. 

3.  Drug companies have developed some interesting other types of therapies that rely on dendritic cell vaccines and a few others.  A vaccine is a bit different from antibodies in that they are material that you can use that comes from the cancer cell itself or from a newly designed product (e.g. human dendritic cells given bits of tumor antigens) to patients to help them boost their anti cancer immunity.  These have limited effects and only work with certain patients and we can’t always anticipate who will benefit and who won’t.  Other approaches include the use of cancer RNA, DNA, cytokine stimulated dendritic cells, etc.  Only one drug in this class has been approved by the FDA so far and that is against very advanced protate cancer.

4. Small peptides (proteins) and other small molecules are being developed now that target various newly discovered cancer specific pathways (again we have learned a great deal about pathways in cancer that don’t exist in normal cells).  In melanoma (skin cancer) about 45 different cancer specific peptides have been identified (ones that the immune system recognizes and trials or pre clinical research is being conducted with many of them). 

5.  We have learned that treating cancers with drugs that target specific mutations (a classic example is Gleevec(R) that targets the BCR:ABL protein in a cancer called CML) have the potential of driving the cancer to become resistant to that drug (via further mutations).  This is somewhat similar to the anti-viral therapy for AIDS (HIV-1 disease).

  6.  We can sub-classify cancer better and stage it better.  It is not clear that this helps with treatment, but it certainly helps to give the patient individualized prognosis (e.g. give them with more accuracy his/her life expectancy with a cancer at a specific stage).  In some cases it does help to prolong life.

7.  Some drugs on the market can now be analyzed for long-term efficacies.  For example, for some drugs that have been used for 10 years or more for the same patient (same cancer) we can come up with better 10 year survival rates, etc.  This, of course, can be done on patients who were treated with a cancer therapy (even immunotherapy) ten years ago, even if the drug was stopped.  We can and have gotten better numbers now at longer term survival (perhaps in the future cure rates will be measured at longer time points than 5 years).

8.  Viral vaccines against papilloma virus for teens (females only) is going to revolutionize the HPV associated cancers.  These vaccines (initiated in many countries now) are going to reduce significantly the risk of getting certain cancer in women…the biggest of which is cervical cancer.  It will be interesting to see if the same can be done in the future for other viral associated cancers such as liver cancer (HCV or HBV), stomach cancer, and a few others (e.g. EBV and NPC). 

Anyhow, there is much we have learned (and this was not comprehensive).  However, it is not clear that we are truly extending the lives of many patients with cancer (better than we were ten years ago).  It seems that for advanced cancer patients we are in the same position as we were years ago.  Certainly for newly diagnosed cancers such as prostate cancer, we can do more now than ever to get most patients to continue to live cancer free lives.  We have a long way to go…we have got to find treatments that work for patients with cancers that have metastasized for example.  We have got to figure out how to keep costs low.  We have got to figure out how to do better screening or if screening is really necessary. Other avenues that are gaining interest are treatment that do not rely on “western medical” interventions.  This area will continue to grow.

Thanks for reading….please leave me comments!

Cancer made simple! 

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