The pharma giant announced that its Enhertu treatment reduced risk of death by 41% in patients with metastatic gastric cancer cases.
The drug, which will move to the final stage of trials, is currently approved in the US and Japan for certain types of breast cancer.
In a separate update, the FTSE 100-listed firm shared update results of late-stage trials on Imfinzi in combination with chemotherapies.
If used to treat extensive-stage small cell lung cancer, it reduced the risk of death by 27%.
Tagrisso increases hope for cure
While the 20-30% risk reduction is the norm in cancer candidates, analysts were impressed by Friday’s morning update on Tagrisso.
The final stage of trials showed that it can reduce the risk of disease recurrence or death by 83% in non-small cell lung cancer patients.
Almost 90% of participants were still alive two years after the trial, against 53% on placebo.
Tagrisso, which is already approved in several countries for advanced or metastatic lung cancer, accounts for 15% of revenue in the first quarter of 2020.
Lung cancer accounts for about one-fifth of all cancer deaths, while 85% of diagnosis are non-small cell lung cancer.
Of these, those 30,000 patients a year who get a diagnosis for early stage, non-small cell lung cancer with an EGFR mutation could benefit from Tagrisso.
According to Shore Capital, peak sales could reach US$5bn per year.
One of the best clinical trial results in oncology history with Tagrisso in lung cancer. New standard of care for EGFR-mutated patients following surgery. https://t.co/hraUXnCxvB— P. Przewiezlikowski (@przewiezlikowsk) May 29, 2020
Although it is not a cure for cancer, it gives hope in preventing cancer from expanding if it is not possible to completely remove it with surgery, analysts said.
Shares, which have jumped 16% in the year to date despite the crisis, rose 2% to 8,905p on Friday afternoon.