Bristol-Myers Squibb on Monday unveiled the first overall survival data from the Phase III CheckMate-067 study, showing that median overall survival had not been reached in patients with previously untreated advanced melanoma who received either Opdivo (nivolumab) alone or in combination with Yervoy (ipilimumab). Meanwhile, the results, which were presented at the American Association for Cancer Research (AACR) annual meeting, indicated that patients given Yervoy alone had a median overall survival of 20 months, with a minimum follow-up of 28 months.
"This level of survival rate at two years is really unprecedented," commented Fouad Namouni, Bristol-Myers Squibb's head of medical and oncology development. Data showed that the two-year overall survival rates were 64 percent for the Opdivo plus Yervoy combination, 59 percent for Opdivo alone and 45 percent for Yervoy alone.
In the study, 945 patients with previously untreated advanced melanoma were randomised to treatment with Opdivo in combination with Yervoy, Opdivo monotherapy or Yervoy monotherapy. The co-primary endpoints of the study were overall survival and progression-free survival, while secondary endpoints included the objective response rate, efficacy by tumour PD-L1 expression level and safety.
Study results showed that Opdivo in combination with Yervoy reduced the risk of death compared to the Yervoy arm by 45 percent, while Opdivo monotherapy was associated with a 37-percent lower risk of death. Meanwhile, the proportion of patients who experienced complete responses in the combination arm reached 17.2 percent, compared to 14.9 percent for Opdivo alone and 4.4 percent for the Yervoy monotherapy arm.
Bristol-Myers Squibb noted that the risk of disease progression versus treatment with Yervoy alone was significantly reduced by 58 percent in the combination arm and 46 percent in the Opdivo monotherapy arm. Additionally, the drugmaker indicated that the objective response rates in the Opdivo and Yervoy combination group, Opdivo monotherapy and Yervoy monotherapy arms were 58.9 percent, 44.7 percent and 19.0 percent, respectively.
The company further said that although the study was not designed to compare the combination regimen to Opdivo alone, the results indicated that Opdivo plus Yervoy reduced the risk of death by 12 percent versus Opdivo monotherapy, with the risk being diminished by 26 percent among patients expressing PD-L1 <1 percent.
Commenting on the news, Evercore ISI analyst Umer Raffat noted that the finding is an important distinction that could have implications for an ongoing study in lung cancer. "Could the [Opdivo and Yervoy] combo have a better shot in the <1 percent PD-L1 cohort," Raffat questioned, continuing "we shall see."
In 2015, Opdivo and Yervoy were cleared  by the FDA for the treatment of patients with BRAF V600 wild-type unresectable or metastatic melanoma, marking the first approval of a two-drug immuno-oncology regimen in the US. Earlier this year, Bristol-Myers Squibb decided against seeking accelerated approval of the regimen in the US for the first-line treatment of lung cancer following a review of data.
For related analysis, read ViewPoints: Opdivo/Yervoy combo improves survival in melanoma, but toxicity remains an issue .