New research suggests oncologists can feel more confident about using immunotherapy to treat cancer in patients with a range of co-morbidities including autoimmune diseases, a conference has heard.
Dr Alex Menzies, a medical oncologist at Melanoma Institute Australia and Royal North Shore Hospital, told the COSA Annual Scientific Meeting that data garnered through clinical trials has not answered questions about how safe and effective immunotherapy is for patients with co-morbidities like auto-immune diseases, organ transplants, chronic viral infections, poor heart or kidney function or brain metastases, who are ineligible for trials.
This has presented challenges for clinicians.
“There’s a whole lot of people we see in clinic every day that come in that would never have got on a trial and yet we need to try and work out whether it is it safe and effective to treat these people with these new medicines that have been such a breakthrough in medicine,” Dr Menzies told the limbic.
To answer this question Dr Menzies and his colleagues carried out a retrospective pooled data analyses based on individual patient outcomes from major cancer centres around the world, looking at the toxicity and efficacy of a range of immunotherapies.
In two studies, they pooled data on outcomes of melanoma patients who had an autoimmune disease and were treated with ipilimumab or anti-PD 1 antibodies, comparing results with clinical trials that used the same drugs.
They found the same rate of usual side effects such as skin rash and thyroid gland inflammation in both cohorts, and similar rates of cancer response, suggesting the treatment can be safe and effective in patients with autoimmune disease.
“What was really interesting was what happened to the underlying autoimmune disease,” Dr Menzies said.
“What we saw was in about 40% of patients these immune diseases flared, but they were very easily managed and very few patients had to stop their immune therapy.
“We saw that rheumatological conditions flare most of the time but others like inflammatory bowel disease or inflammatory nerve conditions seldom flared – and they are the ones we think are more risky.”
The pooled analyses were published in Annals of Oncology in 2017 and JAMA Oncology in 2016.
“The take-home message from these studies is that these drugs can be used safely and effectively in selected patients with autoimmune disease.”
Another pooled analysis looked at patients who had previously had an organ transplant, later treated with immunotherapy.
“There is not a lot of data out there, but certainly there is a risk of rejecting the organ transplant with these drugs, but there are also a large number of patients who have been treated without any rejection of their transplant and some of whom have responded to the therapy as well. So it’s not black and white.
“I think overall what we are seeing is there is a lot of uncertainty with the use of these drugs in the real world, however from the data we are seeing, it looks like these drugs are safe, are active and can be used in the broad population.”
“It means that many patients who may have otherwise been denied treatment can now get potentially life-saving treatment.”
“Most cancers one day will be treated with immunotherapy,” Dr Menzies said.
Currently the only immunotherapy drugs that patients can access on the Pharmaceutical Benefits Scheme are for melanoma, lung cancer and kidney cancer.
Several clinical trials are ongoing across many cancer types, with access likely to expand soon for patients with head and neck cancer, bladder cancer, colorectal cancer and Hodgkin’s lymphoma.