Pharmalot… Pharmalittle… Your ASCO Round-Up
1 CommentBy Ed Silverman // May 15th, 2008 // 11:42 pm
Some folks will be pulling all-nighters reading the abstracts released by the American Society of Clinical Oncology this evening. (Please look here). But if you simply want to glean a few highlights, here are the latest news summaries moving over our transom…
Lilly Drug Slows Lung Cancer (The Wall Street Journal)
Rash Most Common Side Effect In Vectibix Trials (Yahoo/Reuters)
Avastin Improves Brain Cancer Survival (Yahoo/Reuters)
Herceptin Enhances Tykerb For Breast Cancer (Yahoo/Reuters)
Amgen Says Denosumab Combats Rare Bone Tumors (Yahoo/Reuters)
Gregory D. Pawelski
If one enormously expensive drug doesn’t work well for most patients, give two enormously expensive drugs. And if that doesn’t work, trial-and-error three, or four or more. If Tykerb blocks the activation of both EGFR and HER2, why give Herceptin which blocks only HER2? And when there are too many receptors, the cancer cell still continues to grow and divide.
Cancer cells have many mutations in many different pathways, so even if one route or two is shut down by a targeted treatment, the cancer cell may be able to use other routes. Targeted drugs have not been accompanied by reliable, specific predictive tests allowing for rational and economical use of these drugs. Molecular diagnostics approved often have been mostly or totally ineffective at identifying clinical responders to the various therapies.
If you find one or more implicated genes in a patient’s tumor cells, how do you know if they are functional (is the encoded protein actually produced?). If the protein is produced, is it functional? If the protein is functional, how is it interacting with other functional proteins in the cell? Are you sure that you’ve identified every single protein that might influence sensitivity or resistance to these drugs?