(Reuters) - Patients with advanced melanoma who received Bristol-Myers Squibb's immunotherapies Opdivo and Yervoy had improved overall survival compared with those on Yervoy alone, with 64 percent on the combination therapy still alive after two years, according to data released on Monday.
The combination therapy won approval to treat the deadliest form of skin cancer based on its ability to delay disease worsening, known as progression-free survival, with the condition that it ultimately helps patients live longer.
Data presented at the American Association for Cancer Research meeting in Washington for the first time demonstrated that overall survival benefit.
Prior to the introduction of these new drugs that help the immune system fight cancer, including Keytruda from Merck & Co, advanced melanoma was a short-term death sentence.
The new drugs do come at a hefty price. The combination regimen used in the study costs about $145,200, Bristol said.
In the 945-patient late stage trial, median overall survival for Yervoy, known chemically as ipilimumab, was 20 months. Median overall survival had not yet been reached for the combination or for Opdivo (nivolumab) alone, with a minimum follow-up of 28 months.
After two years, 59 percent of those who got Opdivo alone were still alive, while 64 percent of patients in the combination group were alive.
"This level of survival rate at two years is really unprecedented," said Fouad Namouni, Bristol's head of medical and oncology development.
Put another way, the combination therapy reduced the risk of death 45 percent compared with Yervoy, the company said.
No new safety issues turned up in the study, Bristol-Myers said. However, the rate of serious adverse side effects was 58 percent for the combination, 21 percent for Opdivo and 28 percent for Yervoy.
"It is exciting to see that initial results suggest that the nivolumab plus ipilimumab combination provides favorable survival outcomes compared with ipilimumab alone," Dr. James Larkin, the study's lead investigator, said in a statement.
The higher rate of severe side effects should be considered when making treatment decisions, he added.
Bristol-Myers is looking to regain its standing in the burgeoning immuno-oncology field. It ceded its perceived lead to Merck last year, when Opdivo proved no better than chemotherapy as an initial treatment for advanced lung cancer, by far the biggest oncology market. Merck's Keytruda won approval as a first-line treatment for advanced non-small cell lung cancer.
Reporting by Bill Berkrot; Editing by Cynthia Osterman