UPDATED: Bristol-Myers adds promising survival update on breakthrough cancer drug

Bristol-Myers Squibb has added a few more brushstrokes to the very promising picture that's emerging from early-stage studies of nivolumab, a top PD-1 checkpoint receptor inhibitor billed as a major breakthrough in cancer drug research. Updating the early-stage study of the therapy, investigators said that the survival rate for heavily pretreated lung cancer patients hit 42% after one year of therapy and 24% after two years.

The data were drawn from 129 patients with non-small cell lung cancer. This was the same trial that played a starring role at ASCO last summer, as checkpoint receptor inhibitors--designed to unleash an immune system attack on cancer--emerged as a likely contender to fundamentally shift the goal posts of cancer therapy in patients' favor. At that point investigators noted that the median survival time for patients was 16.8 months across all doses.

Analysts followed up with some bullish remarks after the latest trial results arrived.

Seamus Fernandez, an analyst at Leerink Swann, expects a new drug application for nivolumab next year, putting Bristol-Myers in the lead in a three-way race to the market with Merck ($MRK) and Roche ($RHHBY).

The 24% two-year survival rate "represents an impressive improvement over relatively immature data available at ASCO 2013 (which showed 14% alive) and outperformed the mid- to upper-teen mark we were hoping for in this heavily pre-treated patient group," noted Fernandez on Monday.

"Despite what we suspect is still very immature data, the 24% 2-yr OS looks reasonably encouraging and has to be analyzed in the context of third-line therapy," noted ISI's Mark Schoenebaum, an analyst who's been tracking the field. "There are no drugs approved for squamous lung patients beyond second line currently and thus an apples-to-apples comparative analysis is hard to make." In addition, he added, the latest data are pooled among a range of doses, leaving the distinct possibility that the highest doses could be significantly better.

"Our goal with immuno-oncology is to change survival expectations and the way patients live with cancer," said Michael Giordano, senior vice president and head of oncology and immunology at Bristol-Myers Squibb ($BMY). "These are encouraging Phase I results from the expanded cohort of patients with lung cancer, the leading cause of cancer deaths globally, and we are seeking to confirm these early data in ongoing Phase III trials."

Well aware of the commercial implications--these drugs are widely expected to become a standard feature of cancer therapy, often in combination with other drugs--Bristol-Myers has ramped up an impressive slate of 25 studies to hustle nivolumab along to regulators at the earliest possible moment. Seven of those studies are considered registrational studies needed for FDA approval with late-stage trials underway for melanoma, renal cell cancer as well as lung cancer.

The updated results from the study are being presented at the World Conference on Lung Cancer.

Bristol-Myers has some competition to consider. Merck has a competing PD-1 drug--MK-3475--in the clinic and Roche has its PD-L1 drug to boast about. The biological pathway here is simple to understand. Targeting the PD-1 or PD-L1 receptor unleashes a T-cell attack on cancer cells, essentially deactivating a cloaking mechanism that has prevented an immune response. Bristol-Myers Squibb outlined even better response rates with a combination of Yervoy and nivolumab, a potential megablockbuster combination approach that could earn billions of dollars a year.

- here's the press release

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