* No benefit seen in patients with high levels of PD-L1
* Opdivo trial result at odds with success of Keytruda
By Ben Hirschler
COPENHAGEN, Oct 9 Bristol-Myers Squibb
disappointed investors on Sunday as researchers detailed data
for its Opdivo cancer immunotherapy, which was already known to
have failed to do better than older chemotherapies in a closely
watched clinical trial.
Some analysts had speculated the study would at least show
Opdivo worked in a subset of lung cancer patients with a
biomarker that should make them more receptive to immunotherapy,
but there was no sign of this.
Bristol first announced the trial failure in August, since
when its shares have fallen by around a quarter, but experts
have been waiting eagerly to learn exactly what went wrong and
see if something might be salvaged from the setback.
In the event, data on Sunday showed patients actually did
worse on Opdivo, surviving only 4.2 months before their disease
worsened against 5.9 months for those on chemotherapy, although
the difference was not statistically significant.
What is more, researchers told the European Society for
Medical Oncology congress that they were unable to point to any
group of patients who did better in the trial, possibly due to
imbalances between patients in different subsets.
Bristol took a big gamble by accepting a wide range of
previously untreated lung cancer patients into its trial, in
contrast to Merck which succeeded in a similar study by
only taking people with high levels of a protein called PD-L1.
Immunotherapies like Opdivo and Merck's Keytruda work by
taking the brakes off the immune system and are known to be most
effective when tumour cells express lots of PD-L1.
Some investors had hoped Bristol would be able to point to a
clear benefit in patients whose tumours had at least 50 percent
of cells producing PD-L1. However, even in this group the trial
did not show a benefit.
Commenting on the results, Naiyer Rizvi of Columbia
University Medical Center, who was not involved in the study,
said the failure to see a benefit was unexpected and hard to
resolve with other clinical trials.
Bristol's bad news day contrasted sharply with that of
Merck, which was able to point to a double success in clinical
trials using Keytruda.
(Editing by Clelia Oziel)