Pancreatic cancer cell. Credit: LRI EM Unit.
An experimental drug that stimulates the immune system, used in combination with chemotherapy, shrank tumours in patients with pancreatic cancer, according to a preliminary US clinical trial.
Published in The Lancet Oncology, results from the trial suggest the experimental therapy could allow more pancreatic cancer patients to have surgery – offering them the best chance of survival.
However experts cautioned that larger studies would be needed to confirm the findings.
Pancreatic cancer is often diagnosed too late for patients to be offered surgery, as their disease has started to spread. At this point, doctors can use chemotherapy and combinations of other therapies to control the disease, but survival remains low for these patients.
According to study leader Professor David Linehan, based at New York’s University of Rochester Medical Center, any research that could make more pancreatic cancer patients eligible for surgery would be ‘exciting’.
The immunotherapy drug, known as PF-04136309, attacks certain immune cells found in pancreatic tumours. These cells prevent other parts of the immune system from attacking the cancer. Research has shown that the drug can alter this response, and help turn the immune system on again.
The study included 47 patients with the most common type of pancreatic cancer – ductal adenocarcinoma – which had begun to spread. Of the patients enrolled in the trial, 39 received the experimental combination and eight received chemotherapy alone.
The majority of those given the combination saw their tumours stop growing, while some even saw their tumours shrink – known as a partial response. One patient’s tumours disappeared.
Compared to the group which received chemotherapy alone, the response rate for this group was almost double that initially predicted by the team. Furthermore, the early trial results concluded the experimental combination had proved tolerable and safe.
Professor Andrew Biankin, a Cancer Research UK expert in pancreatic cancer based in Glasgow, said: “There is a desperate need for new ways to treat pancreatic cancer. And this promising early stage study suggests that treatments that harness the power of the immune system may be of benefit to people with pancreatic cancer when combined with chemotherapy.
“Immunotherapy treatments have shown real promise for treating other types of cancer, so if a similar approach could be used to treat people with pancreatic cancer that would be great news.
“Just how important this could be for patients now needs testing in larger clinical trials. But if these studies do offer patients a chance of surgery then this could be of great benefit to those affected by pancreatic cancer.”
While three patients withdrew from the trial following side-effects, the overall reaction to PF-04136309 was found to be no worse than with standard chemotherapy.
The team now plans to lead a larger (phase 2) trial to further test the new therapy further.
- Nywening, T., et al. (2016). Targeting tumour-associated macrophages with CCR2 inhibition in combination with FOLFIRINOX in patients with borderline resectable and locally advanced pancreatic cancer: a single-centre, open-label, dose-finding, non-randomised, phase 1b trial. The Lancet Oncology. DOI: 10.1016/S1470-2045(16)00078-4