Researchers at Oxford University are beginning the first human trial of a personalised cancer treatment this week.
The new drug, called CXD101, will be investigated alongside a new test which could predict which patients could be successfully treated by this class of drug.
One of the major challenges in drug development is that each patient responds differently to treatment. The presence of a test which could determine whether a patient could be successfully treated by the drug would save time for patients with quickly-developing cancers, avoid the cost of unnecessary treatments and prevent damaging side effects.
Lead researcher Nick La Thangue, Professor of Cancer Biology at the University of Oxford, said, “This is really the shape of things to come, and avoids the problem of testing drugs on patients who have little chance of benefiting from the treatment.”
Professor Mark Middleton, the clinical lead for the trial and Professor of Experimental Cancer Medicine at Oxford University, said, “As we grapple with the affordability of new drugs we are always looking for ways to define who benefits from new treatments. If we can develop a test to say who should have a new drug we save the NHS money, patients from trying ineffective treatment and spare them side effects unless there’s a good chance of benefitting from treatment. For CXD101 there’s a long way to go to reach this goal, but by evaluating the biomarker from the start we stand the best chance of making it clinically useful.”
The clinical trial will investigate CXD101, a next-generation histone deacetylase (HDAC) inhibitor. This blocks HDAC enzymes, which are important in the regulation of gene expression. Blocking these enzymes can stop cancer cells from multiplying, and may even kill cancer cells entirely.
The test for the efficacy of the drug involves measuring the levels of a protein biomarker, HR23B. A high level of protein has been shown to make tumours more vulnerable to CXD101.
The trial will involve 30-40 cancer patients. The first group will be given increasing doses of the drug to determine the most effective dose. The second group will be tested for the biomarker, and those with high levels will be treated with the best dose of the drug.
This has significant implications for the future of cancer treatment, and can be effective on a wide spectrum of cancers for late-stage cancer patients. Professor La Thangue said, “Any cancer could be high in HR23B, from breast cancers to blood cancers, so we are screening a broad range of patients to identify anyone who might benefit.”
Personalised medicine has been growing in popularity over the past decade to increase the efficiency of treatment. Samuel Kim, a first year medic at Oxford University, said: “Personalised medicine has been the next ‘big thing’ in medicine for a while now, and it is good to see novel treatments being trialled here at Oxford. However, I do worry that it will follow much the same story as gene therapy; something that promises so much, but has delivered so little.”
The drug and associated test are still in Stage I of clinical trials, and it will be a minimum of 10 years before it is implemented as a treatment for cancer.
Marco Narajos, online editor of Bang Science and a first year medic, commented, “Whilst the trial for CXD101 and the biomarker is exciting, we’re definitely not out of the woods yet. Certainly, we don’t know yet if it works, how much it will cost the NHS, and whether it will cause short term or long term side effects, and call me a cynic, but certainly it won’t be a panacea for cancer. The drug is meant for late-stage cancer patients, and potentially it will be useful to extend the lives of these patients, even if for a few months. We can still be hopeful, and I am excited to see the results of the trial.”
