The high price charged for Avastin, a drug that has proved moderately effective against colon cancer and is about to be used against breast and lung cancer, seems hard to justify on any ground other than maximum profit for its maker. The pricing scheme planned by Genentech and its majority owner, Roche, is a sign of how the rising cost of new life-extending drugs may affect American healthcare unless ways are found to mitigate the trend.

Genentech’s pricing for Avastin will drive its cost to $8,800 a month for lung cancer and $7,700 a month for breast cancer, up from the $4,400 cost for colon cancer patients. The manufacturers go beyond the standard argument that high prices are needed to recoup research costs and add a new twist: the price reflects the value of this medicine to society. That is surely debatable. Avastin, while prized by oncologists as a genuine advance, extends the life of a typical patient with late-stage colon cancer by only five months. The drug will add several months to the lives of patients with late-stage breast and lung cancer, though individual patients may do better or worse. Those gains seem modest. This is not a miracle drug, bringing huge benefits to society. The high price seems to have been imposed mostly because the companies figured the market would bear it.