Shares in Bristol Myers Squibb (NYSE: BMY) tumbled again as rival Merck's (NYSE:MRK) immunotherapy drug Keytruda.scored well in a clinical trial for lung cancer.
Bristol Myers’ own immunotherapy treatment, Opdivo, failed its phase III trial for non-small cell lung cancer in August with no improvement in previously untreated patients.
Over the weekend, however, Merck said that Keytruda halved the rate of disease progression and reduced the number of deaths by 40%.
In combination with established chemotherapy drugs, meanwhile, it was twice as effective as chemotherapy alone.
A spokesman for the university where the research was carried out said the results may have marked a new day for lung cancer treatment.
Merck had already announced that Keytruda had performed well in the trial, but this was the first time the data had been published.
Keytruda is part of the new wave of immunotherapy boosting treatments for cancer that enable the body to recognise rogue cells and destroy them.
Lung cancer is seen a US$10bn plus market and while Opdivo is approved for other treatments, its failure here has wiped billions off Bristol Myer’s value.
Shares today were 9% lower at US$50.3 as analysts suggested it may now never catch up Merck, with Keytruda set to become the new standard of care.