Pfizer Sees Hope in Drug to Treat Two Cancers
The first thing you notice after entering Catherine J. Mackey’s roomy corner office at Pfizer Inc.’s sprawling research labs in La Jolla is the Ouija board set out on a table. Mackey jokes she uses the game to divine which of the many molecules from the labs is likeliest to become a successful drug.
Picking a winner is one of the toughest jobs in the pharmaceutical business, but Mackey, the La Jolla research chief, is close to delivering Pfizer’s first biotechnology drug for cancer.
Called Sutent, the drug doesn’t attack cancer cells directly but starves them by cutting off their blood supply. The once-daily pill showed promise in a rare digestive-tract cancer and kidney cancer in company-sponsored studies presented over the weekend at a medical meeting in Orlando, Fla.
Pfizer’s research in the gastrointestinal stromal tumors, or GIST, is furthest along, and Sutent may be approved as a treatment for the digestive-tract cancer next year, analysts say.
The pill moves Pfizer, the marketing behemoth that made Viagra a household word, squarely into a category dominated by science-driven biotechs. Mackey, who had her office painted purple and took up surfing with the scientists from nearby Scripps Research Institute, said it was no accident that Pfizer situated labs in San Diego.
“Here you have the biotech culture,” said Mackey, noting the city contains one of the world’s largest clusters of biotechnology firms.
Sutent is in the same class as Genentech Inc.’s Avastin, an intravenous drug that is on its way to becoming a multibillion-dollar-a-year product. The drugs won’t directly compete because Avastin has not been approved for GIST or kidney cancer. Sutent would be an important addition for Pfizer, which recently withdrew its arthritis pill Bextra and watched Celebrex sales sink.
Behind Sutent is an enormous investment by Pfizer in biotechnology drugs for cancer. The company is plowing nearly $1 billion into cancer research, and has 14 experimental drugs in human tests.
“I’ve been told our oncology portfolio is among the strongest, if not the strongest, in the industry,” William Slichenmyer, vice president for worldwide therapeutics, said at a news briefing in Orlando on Sunday.
A day earlier, the company presented new research at the annual meeting of the American Society of Clinical Oncology showing that Pfizer’s pill significantly delayed progression of cancer in patients with GIST who had become resistant to Gleevec, a Novartis pill. Sutent delayed progression of cancer by 6.3 months compared with 1.3 months for patients on a placebo.
The study was halted in January to allow all patients to receive Sutent, but the results weren’t disclosed until Saturday. Three hundred patients participated in the late-stage clinical trial, the final test needed for Food and Drug Administration approval.
The outcome is significant because most patients develop resistance to Gleevec, the only approved treatment for GIST, after two to three years. The disease affects 2,000 to 5,000 patients a year in the U.S.
The doctor who led the clinical trial, George Demetri of Dana-Farber Cancer Institute in Boston, said the drug was “another source of hope to patients ... another step toward a cure.”
Sutent was effective in shrinking kidney cancer tumors in two early-stage trials, according to research that also was released Saturday. Forty percent of a total of 169 patients with advanced kidney cancer saw their tumors shrink by at least 30%, according to the data. Patients took a two-week break from the drug every four weeks to recover from side effects, which include extreme fatigue. The treatment schedule was the same for GIST patients.
The physician who led the early-stage trials, Robert Motzer of Memorial Sloan-Kettering Cancer Center in New York, said his patients didn’t complain about being tired. About 36,000 patients in the U.S. are diagnosed with kidney cancer each year and one-third of them die. Just 15% of patients respond to standard drugs used to treat the disease.
“These are patients with a lethal malignancy,” Motzer said. “Fatigue is not high on their list of concerns.”
Pfizer is in the process of conducting the final round of tests needed in order for Sutent to receive FDA approval as a treatment for kidney cancer. If those tests are successful, analysts say, Pfizer could begin marketing Sutent to kidney cancer patients in 2007.
By then, Pfizer could face some formidable competition from Onyx Pharmaceuticals Inc., an Emeryville, Calif.-based biotech that has teamed with German drug firm Bayer. The two companies are expected to receive approval of their kidney cancer drug sorafenib by early next year.
But in what some Wall Street analysts described as a marketing coup, Onyx and Bayer have received FDA permission to begin distributing the drug free to advanced kidney cancer patients who have no other options as part of an “expanded access” program. David Bouchey, an analyst with RBC Capital Markets, said sorafenib could become available at some cancer centers by next week and eventually reach 6,000 patients.
The program could widen sorafenib’s lead over Pfizer’s Sutent to 18 months, Bouchey said. “That is a very significant first-to-market advantage,” he said.
Sorafenib, like Sutent, also blocks formation of blood vessels that nourish tumors. On Saturday, the companies revealed results of a clinical trial of 900 patients, the final human test needed for FDA approval. Sorafenib delayed progression of cancer by six months compared with three months for patients on a placebo. The once-daily pill also causes fatigue, but it is not so severe that patients need a break from treatment.
Michael Atkins, a cancer specialist at Beth Israel Deaconess Medical Center in Boston, said, “When patients go on these drugs, they stay on them forever.” Patients will decide “what [side effects] they can live with.”
Pfizer picked up Sutent as part of its acquisition of Pharmacia in 2003, a deal that made New York-based Pfizer the world’s largest drug company. Almost immediately, Pfizer put the Sutent program under review. Scientists who had been working on the drug worried it might be canceled.
“Pfizer is such a huge company and this is just a speck,” said one of the scientists, Laurie M. Strawn, who is now with Pfizer.
In Boston, Demetri also was concerned and thought about synthesizing the drug in his lab at Harvard Medical School if Pfizer dropped the project. He contemplated getting foundations to fund the project.
Pfizer surprised them all when it greenlighted clinical trials in GIST and kidney cancer. But it put Pharmacia’s plan to broadly test Sutent in breast, lung and colon cancer on hold until recently. Slichenmyer said that Pfizer had to spread its research dollars across many disease categories. But the delay meant Sutent fell behind Avastin in three common cancers.
You won’t find Mackey’s team consulting the Ouija board to determine the outcome of this drug race.
Michael Varney, head of drug discovery in La Jolla, said, “What does it take to have a successful drug? You need the best clinical program, the best marketing. We’re in this to win.”
While the total U.S. markets for Sutent in GIST and kidney cancer don’t exceed $750 million, Lipitor, Pfizer’s cholestorol-lowering drug, posted 2004 sales of $10 billion.
