about $150 million annually in U.S. sales. The FDA’s deadline to make a decision is April 23.
The FDA’s advisory panel meetings can dwell on the most arcane and tangential of scientific questions, but the ultimate question usually comes down to whether the panel thinks that the evidence presented for a drug is strong enough to show that the benefit outweighs the risk—or whether more proof from clinical trials is necessary. Adam Feuerstein, an influential biotech columnist of TheStreet.com, published his seven-point case on what he sees as the weak spots in the Cell Therapeutics application.
The 140-patient study on which Cell Therapeutics’ case heavily relies is known as Extend or PIX 301. This study randomly assigned patients to get pixantrone or the physician’s choice of another chemotherapy drug. The study’s main goal was to show the treatment could completely wipe out tumors. The study reached its goal, and the finding was statistically significant. About 20 percent of patients on pixantrone (14 out of 70) had a “complete response” compared with 5.7 percent (4 out of 70) who did that well in the control group.
What about side effects? Patients in the pixantrone group had higher rates of white blood depletion, known as neutropenia, with 41 percent reporting a severe case of that effect, compared with 19 percent in the control group, according to data presented in June at the American Society of Clinical Oncology. An even more severe form of that condition, febrile neutropenia, was found in 7.4 percent of pixantrone patients, compared with 3 percent in the comparison group. There were also more cases of severe cardiac disorders reported among patients who got pixantrone—8.8 percent on the drug, compared with 4.5 percent in the control group.
While cancer drugs are allowed to have greater side effects than a new pain reliever
