By Bill Berkrot
Dec 8 (Reuters) - A closely watched leukemia drug developed by Johnson & Johnson and Pharmacyclics Inc maintained its effectiveness in keeping the disease at bay for most patients, according to long-term follow-up data from a midstage study being presented at a major medical meeting.
The oral drug, ibrutinib, last month won U.S. approval to treat a rare and aggressive form of non-Hodgkin lymphoma known as mantle cell lymphoma. It is awaiting a Food and Drug Administration decision on treating chronic lymphocytic leukemia (CLL), a slowly progressing form of blood cancer that primarily affects people aged 65 and older.
Some industry analysts had expected the CLL approval to come at the same time as the lymphoma decision. Data from this and other studies being presented at the American Society of Hematology (ASH) meeting in New Orleans could give regulators additional comfort about the medicine's safety and effectiveness in treating CLL.
"Patients receiving ibrutinib are doing much better than historically what we're used to seeing with CLL," Dr John Byrd, a co-leader of the study, said in a telephone interview.
The 148-patient ibrutinib extension study looked at both previously untreated CLL patients and those who had relapsed or stopped responding following prior therapies.
With a median follow-up of more than 27 months of treatment, nearly all of the previously untreated, or treatment-naive, patients and almost three quarters of the relapsed and refractory patients had no evidence of the disease progressing.
REMISSIONS CONTINUE
"With extended follow-up the remissions with ibrutinib appear to be continuing and the safety of this long-term is being maintained," said Byrd, professor of internal medicine and director of hematology at the Ohio State University Comprehensive Cancer Center in Columbus.
"There has not been an increase of infections or other late-term complications, suggesting that it's going to be a drug that patients can take for a continued, extended period of time without it being a detriment," he added.
Researchers had not yet been able to determine median progression-free survival - the point at which the disease begins to worsen for half the patients in a study.
Among previously untreated patients, about 96 percent had not yet experienced disease progression, with just one of 31 patients in that group relapsing so far, researchers said.
Typically you would expect about 50 percent to see disease progression at two years, Byrd explained.
"You don't even need a statistician to see the difference. The data are better," he said.