The trial involved 732 patients in hospitals across the UK, German, Sweden and France who had undergone surgery to remove their tumour. Around half of patients on the trial received one chemotherapy drug, gemcitabine, and the other half received a combination of chemotherapy drugs, gemcitabine and capecitabine.
At this time the standard treatment for patients who have undergone surgery is for them to be administered gemcitabine alone.
According to the study twenty-nine per cent of the patients given a combination of the two chemotherapy drugs lived for at least five years compared with only 16 per cent of patients given gemcitabine alone.
The study, which has been published in The Lancet, states that this new combination of drugs approach should be the new standard of care for pancreatic cancer patients who have had surgery to remove their tumour.
This trial was originally set up in 2008 to address the poor pancreatic cancer survival rates.
The results, which were first presented at the American Society of Clinical Oncology (ASCO) in June 2016 but have now been peer-reviewed, show that this treatment plan is predicted to double the number of patients who survive their disease for at least five years.
Trial lead, Professor John Neoptolemos at the University of Liverpool's Institute of Translational Medicine, and Director of the Liverpool Clinical and Cancer Research UK Trials Unit, said: "This is one of the biggest ever breakthroughs prolonging survival for pancreatic cancer patients.
"When this combination becomes the new standard of care around the world, it will give many patients living with the disease valuable months and even years."
Peter Breaden, 67, a retired lab manager and grandfather of five from Merseyside, was diagnosed with pancreatic cancer in April 2010. Following surgery in May 2010 he was to start chemotherapy in the July and was offered the chance to take part in the trial.
Peter said: "I know that new drugs and techniques need to be developed so when the doctors told me about the trial, there was no hesitation in my mind - I wanted to get involved.
"I was very grateful for the opportunity to contribute to this trial. For six months I had chemotherapy on three weekly cycles after my surgery. I am pleased to have been part of a trial that has been such a success. Research is absolutely essential and needs all our support."
Professor Peter Johnson, Cancer Research UK's chief clinician, said: "Pancreatic cancer is a notoriously difficult disease to treat. Nearly 10,000 patients are diagnosed each year in the UK so we urgently needs new ways to treat and manage the disease.
"Research that tells us more about how the disease grows and spreads - and trials like this one - will be key to improve survival for patients living with the disease."
Neoptolemos JP, Palmer DH, Ghaneh P, Psarelli EE, Valle JW, Halloran CM, Faluyi O, O'Reilly DA, Cunningham D, Wadsley J, Darby S, Meyer T, Gillmore R, Anthoney A, Lind P, Glimelius B, Falk S, Izbicki JR, Middleton GW, Cummins S, Ross PJ, Wasan H, McDonald A, Crosby T, Ma YT, Patel K, Sherriff D, Soomal R, Borg D, Sothi S, Hammel P, Hackert T, Jackson R, Büchler MW; European Study Group for Pancreatic Cancer.
Comparison of adjuvant gemcitabine and capecitabine with gemcitabine monotherapy in patients with resected pancreatic cancer (ESPAC-4): a multicentre, open-label, randomised, phase 3 trial.
Lancet. 2017 Jan 24. pii: S0140-6736(16)32409-6. doi: 10.1016/S0140-6736(16)32409-6.