With nanotechnology, scientists triple efficacy of breast cancer drug

NEW DELHI: Cancer drugs come with a host of side-effects. A lot of research has gone into ensuring they don’t end up killing cells they are not meant to, or start piling up in organs they should heal. Docetaxel, widely used to treat breast cancer, has been one such ‘problem’ drug. It’s highly toxic, difficult to target and keeps accumulating in the body.
Now, a group of scientists from Haryana and Delhi have fine-tuned a method to use docetaxel safely, with nanotechnology.In India, one in 22 women develops breast cancer and this procedure could potentially help lakhs.
“Docetaxel is a very old drug. It was developed at a time toxicity standards were not stringent. So, we wanted to create an alternative,” Dr Avinash Bajaj, corresponding author of the study published in the reputed German journal ‘Angewandte Chemie’, told TOI. The main problem with docetaxel is that it’s not water-soluble. “That causes high toxicity, especially in the liver and kidneys.” Bajaj and his team — from the Regional Centre of Biotechnology (Haryana), Amity University (Haryana) and National Institute of Immunology (New Delhi) — switched to nanomicelles, a type of nanoparticle which is water-absorbent outside but not inside.
“Nanoparticles help to make the drug more soluble … Kidneys quickly excrete small drug molecules out, but nanoparticles reduce drug excretion significantly. As a result, more of the drug accumulates in the tumour and not in the other organs. The treatment outcome is 2-3 times better than it is with the FDA-approved docetaxel,” Bajaj said. When they gave a conventional dose to four rabbits, all died. Those administered the drug through nanomicelles survived.
Even with drugs that use nanotechnology — there are a few —a vehicle is needed to take the nanoparticles to the tumour. “Most nanoparticle-based drug delivery systems lead to uncontrolled release into the blood, causing systemic toxicity. We have used the strategy of vehicle-less delivery. We pair it with a lipid, fat. More docetaxel is delivered in a single dose and it is targeted at the tumour,” Bajaj said. “Intravenous injection causes accumulation of the nanomicelles inside the tumour, sparing other organs. The enzymes produced inside the tumour break the chemical bond, release the docetaxel and the tumour cells are killed.”
Using nanotechnology to deliver cancer drugs also opens up options for a wider range of patients. “It is especially useful for those who have an allergic response to chemotherapy or have high blood sugar,” said Dr Suhas Aagre, medical oncologist at the Asian Cancer Institute, Mumbai. “Nano meds are 15-20% more expensive. But the outcomes are better.” Bajaj added that the procedure could also be applied for treatment of other diseases like Covid-19 or to deliver anti-inflammatory drugs like steroids.