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A cancer cure in an ice cream tub

Rapamycin was developed from Easter Island soil. De Agostini/Getty Images

In 1982 a microbiologist smuggled old ice cream tubs over the border from Montreal to New Jersey – in them was a mysterious compound “that was going to become a billion-dollar drug and save millions of lives”, says Avir Mitra in The Dirty Drug and the Ice Cream Tub, a Radiolab podcast. In the 1970s Surendra Nath Sehgal had created, developed and patented rapamycin, a drug that suppresses the immune system. But his employer, a pharmaceutical company, decided it had no use.

Sehgal was convinced otherwise, so he stole his samples and put them in his home freezer. When his job was relocated from Montreal to New Jersey, the samples in their tubs went too, ending up in the family freezer. (Rapamycin was developed from a soil sample taken from Easter Island, hence its nickname “the dirty drug”.) Five years later, at another pharmaceutical company, he realised his immuno-suppressant drug might help patients with kidney disease – transplants were a new field, and organ rejection was a huge problem. Amazingly, the home-frozen samples were still active. Sehgal experimented with help from other scientists, and by 1999 had won official approval for rapamycin. Sure enough, the drug transformed organ transplantation.

By then, Sehgal had been diagnosed with stage 4 colon cancer. Given just six months to live, he turned to rapamycin, which arrests cell growth. He began self-administering – and his tumour disappeared. But was his recovery down to rapamycin? To find out, he stopped taking it, even though his wife begged him not to. Sadly he soon had an answer: the cancer spread irrevocably to his lungs. Sehgal died in 2003, aged 70.

Today rapamycin is vital as a treatment for renal cancer and is used to prevent the rejection of stents, the small devices transplanted into hearts to keep them pumping. There’s also promising research into its ability to stimulate anti-ageing effects in areas such as cognitive ability, heart disease and strokes. Thank goodness those ice cream tubs stayed frozen all those years.

Listen to the podcast here.