Two cancer drugs from Bristol-Myers Squibb Co. could change the standard of care for patients with deadly skin and blood malignancies, according to new studies.
The leukemia pill Sprycel worked better and faster at eliminating malignant cells than Novartis AG’s Gleevec, the standard treatment, a study of newly diagnosed patients found. The drug ipilimumab kept about a quarter of patients battling late-stage melanoma alive for two years -- about twice the proportion with current therapies, a separate trial showed.
The drugs are central to a plan by the New York-based drugmaker to bolster its share of the $52 billion cancer market, and counter generic competition by 2016 to products with $11 billion in annual sales. Sprycel sales could rise with expanded approval as a first-choice therapy. Ipilimumab, if approved, would be the first new melanoma drug in more than a decade, and the only one shown to extend survival in the sickest patients in a large-scale study, said Renzo Canetta, Bristol-Myers’s vice president of oncology clinical research.
“I’ve been taking care of patients with melanoma for almost 25 year and these results are really significant,” said Lynn Schuchter, chief of hematology at the University of Pennsylvania Health System, at the American Society of Clinical Oncology meeting in Chicago, where the data was reported today. “We have not had any therapy that has prolonged survival for patient with stage-four melanoma, period.”
$1 Billion in Sales
Once approved, ipilimumab may have $1 billion in annual sales within five years, said Linda Bannister a health-care analyst at Edward Jones & Co. in Des Peres, Missouri. Expanded use of Sprycel, already approved as a second-line option for patients who fail on Gleevec, could more than double sales to $900 million by 2015, said Tony Butler, an analyst with Barclays in New York.
Bristol-Myers said it plans to use the Sprycel finding to seek expanded U.S. approval for the drug as an initial treatment for the form of blood cancer called chronic myelogenous leukemia or CML. The company said in March it plans to seek regulatory clearance for ipilimumab this year and aims to get it in the hands of doctors in 2012.
“Sprycel could become the next frontline drug for CML and could replace Gleevec,” said Hagop Kantarjian, a leukemia specialist at the University of Texas MD Anderson Cancer Center in Houston, who studied the drug. “For anyone who has a new diagnosis, they should consider this new kind of inhibitor as a viable option that could be better.”
History of Gleevec
Gleevec was the first drug approved that suppresses a cell signal known to cause cancer rather than poison the tumor cells, as with chemotherapy. Before Gleevec became available, CML patients lived an average of three to five years, according to the American Society of Hematology. Novartis is also racing to get a next-generation leukemia drug, Tasigna, approved as a first-line therapy.
The latest study on Sprycel focused on its ability to attack cells with a defective chromosome in the bone marrow called the Philadelphia chromosome, named after the city where it was discovered. In CML, which affects about 5,000 people a year in the U.S., the Philadelphia chromosome produces a gene called Bcr-AbL, which leads to the overproduction of white blood cells. Gleevec, Sprycel and Tasigna stop this chain of events.
In the study, 77 percent of patients taking Sprycel had a confirmed complete cytogenetic response, meaning no cells with the Philadelphia chromosome could be found, compared with 66 percent taking Gleevec. An absence of tumor cells is an indicator of longer survival, said Canetta in a telephone interview. The study followed 519 newly diagnosed patients for at least 12 months.
Patients given Sprycel were more likely to have a loss of platelets and fluid build-up in the lungs while patients taking Gleevec were more likely to have fluid retention under the skin. Patients taking Gleevec were also more likely to have nausea, rash and muscle pain.
Doctors will probably need longer-term data on the benefit of Sprycel and Tasigna over Gleevec for 24 to 36 months before they routinely prescribe the newer treatments as a first-line therapy, said Seamus Fernandez, an analyst with Leerink Swann & Co. in a research report.
Price may also keep doctors and patients on Gleevec, said Kantarjian. When generic copies of Gleevec enter the market in 2015 it will cause the price to fall from its average wholesale price of $4,340 for a month’s supply. The wholesale price of Sprycel is $6,950 at the 100-milligram dose, Bristol-Myers said. Cancer Institute said in a July 2008 report.
The ipilimumab trial, funded by Bristol-Myers, followed 676 patients with advanced melanoma who had failed to benefit from two treatments currently available, interleukin-2 or dacarbazine. It was divided into three parts, with one group getting ipilimumab, a second an experimental cancer vaccine developed by the National Cancer Institute called gp100, and the third a combination of the two.
Patients taking ipilimumab alone lived an average of 10.1 months, according to the study, almost four months longer than those given the gp100 vaccine.
Combining the two drugs produced no additional improvement compared with ipilimumab alone. While 24 percent of patients on the Bristol-Myers drug were still alive two years after entering the trial, only 14 percent of those on gp100 lived that long.
Ipilimumab is derived from mice that were genetically altered to create a human version of an antibody, a part of the immune system. The antibody is designed to accelerate the immune system, enabling a second component, white blood cells called T-cells, to go after the cancer the same way they would a foreign invader such as a virus.