TIRUCHY: The Harshamitra Super Specialty Cancer Centre here, which is among the first in the country to conduct Phase II trials of low-dose radiation therapy for Covid-19, has submitted its preliminary results to ICMR and medical journals, which show oxygen demand of patients coming down by as much as half within 48 hours of reception of a single dose.
The trial, named WINCOVID-19, was registered in ICMR/CTRI in October 2020, and has recruited about 50 patients so far. As per doctors, the preliminary results from 25 patients under the trial have shown rapid improvement in oxygenation status within 48 hours of reception of a single dose of radiation treatment. The recovery rate is 88 per cent.
HOW RADIATION THERAPY WORKS ON COVID INFECTION
“Our trial has been designed in such a way that we don’t deny any treatment as per standard government guidelines. We give low-dose radiotherapy apart from the regular treatment. This treatment does not work on the virus, it works on the immune system. Most Covid deaths occur due to immune overreaction, called cytokine storm. Low-dose radiotherapy brings an anti-inflammatory effect. It acts on inflammatory cells, called macrophages. There are two types of macrophages: pro-inflammatory and anti-inflammatory. Low-dose radiotherapy reduces pro-inflammatory macrophages and increases anti-inflammatory macrophages,” said Dr G Govindaraj, surgical oncologist. Ideal candidates are those who require oxygen and have CT scores below 20/25 (<80 % lung damage). Radiation therapy makes sure that the patients don’t deteriorate further.
“Ideally, it should be given a week from de-saturation (oxygen levels going down). If it is given after more than two weeks, the response is less,” Dr Govindaraj added.
The trial has now completed the exploratory phase and found that the radiation therapy is not associated with any acute toxicity and is associated with rapid improvement in oxygenation status and rapid improvement in the well-being of the patients. The dose of radiation used is 0.5 Gy, called as low-dose radiotherapy. It is less than one hundredth of dose of radiation used in cancer treatment.
PRELIMINARY RESULTS
Most patients who required 8-10 litres of oxygen required only 4-5 litres within 48 hours of the radiation treatment. Most patients in the study returned to ambience air in four to five days.
Emory University in the US and AIIMS, New Delhi published their preliminary results of their phase I trials last year.
The WINCOVID-19 trial is now in the comparative phase, evaluating the difference in outcome between the patients who have been treated with radiation and those who have not been treated with it.
Dr Govindaraj is the principal investigator of this study. Dr P Sasipriya and Dr Vivek Sundaram are the co-investigators. Dr Praveen Kumar M, Dr Venkatraman P, D Manigandan, Dr Gunasekaran, Dr Janakiraman, Brindha T, Prabhu R, R Shree Vaishnavi, Manimaran R and Selva Kumar K form part of the trial research team.