This Drug ‘Sponge’ Sits in the Veins to Minimize the Side Effects of Chemo

Chemotherapy is a lifesaver for millions of patients. Since its advent, chemotherapy has saved the lives of millions of people and prolonged the lives of millions more.

Most chemo drugs are very strong – they have to be – and doctors walk a fine line between giving too little, which would not work well, and giving a higher dose that will kill the cancerous cells but will cause major side effects.

Any use of chemo usually comes with nausea, vomiting, immune system suppression and hair loss. The fear of the harsh side-effects leads many cancer patients to not want to undergo chemo in spite of the potential benefits of the drugs.

If you google chemo side-effects, you see page after page of medical advice on what to do to alleviate the symptoms. But what patients really hope for is no side effects at all. A new medical discovery can actually mitigate these side effects without giving up any of the benefits of chemo treatment.

Scientists have created sponges that when inserted into the bloodstream will absorb excess drugs and prevent dangerous side effects, according to a UC Berkley news release. Chemo may even be able to be used in higher doses to some tumors that do not respond to other treatments.

The drug sponge is actually an absorbent polymer coated onto a cylinder that is 3-D printed specifically for every patient to perfectly fit into the vein that carries blood flowing outside of the organ being treated.

Once inserted, the ‘sponge’ sops up any of the drugs that the tumor does not absorb and prevents them from reaching and possibly harming other organs. When tested in pigs, the polymer absorbed 64 percent of the chemo drug injected.

“Surgeons snake a wire into the bloodstream and place the sponge like a stent, and just leave it in for the amount of time you give chemotherapy, perhaps a few hours,” said Nitash Balsara, a professor of chemical and biomolecular engineering at the University of California, Berkeley, and a faculty scientist at Lawrence Berkeley National Laboratory.

The device is part of a collaboration of UC Berkeley, University of California, San Francisco, and the University of North Carolina at Chapel Hill.

Steven Hetts, the Chief of Interventional Neuroradiology at the UCSF Mission Bay Hospitals, treats tumors of the eye and brain by threading catheters through the bloodstream directly to the tumor site, but half the dose escapes the target organ. He started thinking about how the blood could be filtered to prevent this and approached Balsara in search of a solution.

“An absorber [or sponge] is a standard chemical engineering concept,” Balsara said. “Absorbers are used in petroleum refining to remove unwanted chemicals such as sulfur. Literally, we’ve taken the concept out of petroleum refining and applied it to chemotherapy.”

The results of the study were published on January 9, 2019, in ACS Central Science, an open-access publication of the American Chemical Society.

The team is looking to obtain conditional approval from the US Food and Drug Administration to investigate the use of the sponge in humans. The chances of this being approved are pretty good because the chemo filter is a temporary device that is being used with an already existing and approved treatment.

Testing in humans is still a couple of years away according to Hetts. If this device is approved, it could go a long way in making cancer treatment gentler and in many cases, more effective.