Life-saving cancer drugs help earn large pharmaceutical companies like Novartis billions of dollars annually — and doctors say enough is enough.

In a new study published online in the American Society of Hermatology's medical journal Blood, 120 cancer researchers are fighting back, claiming that Big Pharma's premium on cancer-fighting drugs are unsustainable, expensive, and unambiguously unethical.

"As physicians, we follow the Hippocratic Oath of "Primum non nocer", first (or above all) do no harm," they write [PDF]. "We believe the unsustainable drug prices in CML [chronic myeloid leukemia] and cancer may be causing harm to patients."

Take Gleevec, for example, which CNN Money reports is widely heralded as a "miracle pill." Since 2001, it's been shown to dramatically increase a patient's chances of surviving CML, transforming it "from a lethal disease to one that is usually chronic but manageable." It's akin to taking daily medication for diabetes, and cost $30,000 a year when it first hit the market — which is pretty expensive as is.

Then the price skyrocketed:

"We agree with those who say the price we have set for Gleevec is high. But given all the factors, we believe it is a fair price," Daniel Vasella, Novartis' CEO at the time, wrote in Magic Cancer Bullet, a 2003 book he penned about his company's wonder drug.

That "fair price" nearly tripled over the past decade. An annual course of Gleevec now wholesales for more than $76,000 in the U.S., according to Novartis. The retail price that patients or their insurers pay is typically much higher. [CNN Money]

How much higher? Analysts say it now costs around $100,000 a year to gain access to this life-saving drug.

"If you are making $3 billion a year on Gleevec, could you get by with $2 billion?” Dr. Brian Druker, director of the Knight Cancer Institute at Oregon Health and Science University, tells the New York Times. "When do you cross the line from essential profits to profiteering?"

In 2012, Gleevec earned Novartis $4.7 billion — easily the company's best-selling drug ever. Big Pharma argues that high prices are necessary to fund the cost of research, development, manufacturing, and more. But a recent TIME cover story (subscription required) shows the toll that such logic has taken on the health care system, with a hard look at the exorbitant cost of medical bills. In addition to bankrupting families and sending them into debt, medical expenses now account for an estimated 20 percent of the United States' GDP — $2.8 trillion for 2013.

"I am sure I am going to be blackballed," says Dr. Hagop Kantarjian, the Blood study's lead author and chairman of the leukemia department at the University of Texas' MD Anderson Cancer Center. "My research career will be hurt… [But] pharmaceutical companies have lost their moral sense."