Peroxide injections may boost radiotherapy treatment

Peroxide injections may boost radiotherapy treatment

Hydrogen peroxide, which is used as a common disinfectant, could help make radiotherapy for cancer treatment more effective. Injections of peroxide combined with sodium hyaluronate, an ingredient used in skin care and which is also licensed for treating stiff knee joints, may make the environment at the point of injection more toxic for cancer cells in a tumour.

Studies involving breast cancer patients in Japan have found that Kochi Oxydol Radiation Therapy for Unresectable Carcinomas (KORTUC) leads to more successful treatment with radiotherapy than radiation therapy alone. In one study published in the September 2021 issue of Molecular and Clinical Oncology, half of 30 breast cancer patients who had bulky tumours over 5cm in diameter who were expected to survive at least a year, had clinical complete response after three months, in other words
the tumour was no longer identifiable on scans.

Now the injections will be tested in a UK phase 2 trial on WOMEN with larger tumours or those who disease has spread beyond the breast. Breast cancer patients often have radiotherapy after surgery to lower the risk of the cancer coming back the bigger the tumour, the worse the success rate. Radiotherapy is also offered to patients with breast cancer that has spread to the bone or brain, for instance, which cannot cure the disease but can extend survival and improve quality of life.

There is limited data on how effective radiotherapy can be for those women with locally advanced disease, when it has not yet spread beyond the breast and local lymph nodes, and lots of factors change the outcome including size of the tumour age and whether the cancer is hormone receptor positive. In one major retrospective study published in the November 2021 issue of Oncology which looked at over 41,000 patients with LABC, compared with no radiation, patients with locally advanced breast cancer receiving postoperative radiotherapy had a 38 per cent lower risk of mortality than those who did not received radiation therapy. The 5-year survival rate was 80 per cent for LABC patients who received postoperative radiotherapy but just around 60 per cent for those who had no radiotherapy. KORTUC could widen this gap still further by making radiotherapy more effective.

Now a trial involving 184 breast cancer patients, starting in September 2025 at six hospitals in the UK including the Marsden and two medical centres in India, to further investigate the effectiveness of the injection in women with larger tumours and where the cancer has spread to local lymph nodes.

In an earlier trial at the Royal Marsden NHS Trust in London, involving 12 women with breast tumours sized 3cm or more in diameter which were surgically inoperable showed that the jabs helped control tumour growth or up to two years.

The women received twice weekly injections (the injection procedure lasts 10-15 minutes and is done under local anaesthetic) of the mixture directly into their tumour for three weeks before they had radiotherapy. The results of the study, published in the International Journal of Radiation Oncology, Biology and Physics in 2020, showed that the injections alongside radiotherapy appeared to be safe and in women who had not responded well to other therapies, including chemotherapy or biological therapies it helped control the growth of a tumour for between 12-24 months.

IN THE NEW KORTUC trial, sponsored by the Institute for Cancer Research London, half the group of patients will receive the injections plus radiotherapy and the other half will receive radiotherapy only.
‘Hydrogen peroxide is a cheap, well understood and readily available compound, and our study shows that it could boost the effectiveness of radiotherapy,’ says Dr Navita Somaiah, A clinician scientist at the Institute for Cancer Research and clinical oncologist at the Royal Marsden. ‘Our hope is that using this solution will mean that many patients with breast cancer will be able to have more effective treatment, or even open up new treatment options.’

She says that the treatment could be used for ‘multiple cancer types’ and adds this new trial ‘will test whether it is as promising as we expect for improving outcomes for patients’. While we know it best as a cleaning agent in fact hydrogen peroxide is produced by every cell in the body and has a range of functions including acting as a messenger between cells. At higher levels, it becomes toxic to DNA, as well as the membranes around cells and other essential cell components such as proteins and hormones.
THE solution in this injection is many times weaker, 0.5 per cent, compared with the amount of F Hydrogen peroxide used in antiseptic wipes to sterilise wounds and cuts and household cleaning products.

THE hydrogen peroxide in the body is broken down into oxygen and water by an enzyme catalase, and harmlessly excreted from the body. However the injection creates a high oxygen environment in the tumour which stresses the cancer cells, which have evolved to thrive in low-oxygen environments. They have evolved to be this way because cancer tumours can grow rapidly and the network of blood vessels bringing oxygen to their cells OFTEN can’t keep up, leaving some cells starved of oxygen, or ‘hypoxic’. As a result being in the oxygen-rich environment created by the hydrogen peroxide weakens the cancer cell which then becomes vulnerable to radiotherapy.

KORTUC was Invented by Professor Yasuhiro Ogawa, an emeritus professor at the faculty of medicine at Kochi University in Japan in 2006 and was originally developed for treating advanced breast cancer, soft tissue sarcoma and cervical lymph node metastasis but it has also shown significant effects on tumours in the lung, bones, soft tissue and urological system.

A 2023 study published in Oncology Letters involving 14 women with recurrent cervical cancer, found that KORTUC II, given two hours before interstitial brachytherapy (ISBT), a form of radiotherapy administered as radioactive pellets placed within the tumour, improved the prognosis for patients. The tumour did not get bigger in 79 per cent of patients who underwent ISBT as well as KORTUC, compared with 63 per cent of those having only radiotherapy. The reported side-effects of KORTUC have been limited to discomfort at the injection site for up to 24 hours.

Dr Hattie Brooks, research information manager at Cancer Research UK says: ‘While the Phase 2 KORTUC study is in its early stages, we look forward to seeing whether the findings of this study could help improve the effectiveness of radiotherapy for some types of breast cancer, helping more people with the disease live longer, better lives.’

Professor Karol Sikora, a clinical oncologist based in London and former director of the World Health Organisation Cancer Programme, is more cautious. He told Good Health: ‘We have only seen a preliminary study so far and there were only 12 patients in study. There are a lot of good ideas but it needs a lot more work to study the dose response and potential for unpleasant side effects. The phase 2 trial results are necessary before anyone will get excited.’