Newer Drugs Beat Gleevec for Leukemia
Sprycel, Tasigna May Become Options to Treat Newly Diagnosed Chronic Myeloid Leukemia
Sprycel vs. Gleevec continued...
A total of 1.9% of patients on Sprycel and 3.5% of patients on Gleevec progressed to more aggressive states of CML known as accelerated or blast phases, in which leukemia cells build up and become more abnormal, causing symptoms to appear or become more serious.
While it's too soon to know if the drug extends lives, the improved responses in the Sprycel group suggest "it will significantly improve the long-term outcome" of CML patients, Kantarjian tells WebMD. The patients continue to be followed.
Kantarjian consults for Sprycel maker Bristol-Myers Squibb, which funded this study, as well as Novartis Pharmaceuticals, which makes Tasigna and Gleevec and funded the second study.
Tasigna vs. Gleevec
In the second study of 846 patients, cancer cells were almost completely wiped out in the bone marrow of about 80% of patients on Tasigna by one year, compared with 65% of patients on Gleevec. The rates of major molecular response were about 44% and 22%, respectively.
Tasigna "produced more responses and better outcomes for patients," says study head Giuseppe Saglio, MD, of the University of Turin, Italy.
All three drugs "have outstanding safety profiles," Charles Sawyers, MD, of Memorial Sloan-Kettering Cancer Center in New York, writes in an editorial in the New England Journal of Medicine. There are modest differences in side effects that may lead one patient to choose one drug over another, he writes.
For example, muscle cramps and fluid retention are more common with Gleevec, while changes on liver function tests are more common with Tasigna, he writes. Rashes and headache were more common among both Sprycel and Tasigna users than among patients on Gleevec in the new studies.
But one-year results may make it too early to "claim complete victory" against CML, Sawyers writes.
Ironically, it may come down to economic considerations, he writes, noting that Gleevec could become available in a much cheaper generic form when its patent expires in a few years.
Currently, a month's supply of Gleevec costs about $4,200, and Tasigna can run $7,900 per month, according to Novartis, which makes both drugs.