Patients at Mumbai’s Tata Memorial Hospital had long been taking papaya leaf extract between chemotherapy cycles, usually without their doctors’ approval. The hospital decided to find out whether it did anything. The answer, published in 2026, sounded like a win. It has since turned into an argument.
The claim
Chemotherapy often knocks platelet counts down, sometimes as low as 50,000-1,00,000 per microlitre, when a normal count runs from 1,50,000 to 4,50,000. That raises the risk of bleeding and oncologists end up postponing treatment or lowering doses. The usual fix is a drug called romiplostim. “It is effective but is expensive and comes with side effects,” said Dr Vikas Ostwal, who led the study and teaches medical oncology there. The Times of India put the cost at up to Rs 15,000 per week.
The trial enrolled 219 patients with solid tumours. They were randomly given either a standardised papaya leaf pill or a placebo, alongside usual care. Ostwal’s team reported that the extract group recovered platelet counts significantly faster, had fewer treatment delays and dose cuts, and more often stayed on schedule. The dose was three tablets a day, at Rs 300 for a 10-day course. The paper appeared in JCO Global Oncology, the ASCO journal. Dr Sudeep Gupta, the hospital’s director, said the work “could benefit cancer patients not only in India but also across the world.”
The idea had a long tail behind it. Papaya leaf is a folk remedy for dengue, where platelets also fall, and small studies in India and Malaysia pointed that way.
The objections
Then the journal flagged the paper. It added a note saying it had been alerted to potential concerns about reproducibility and clinical interpretation and was investigating. The request came from Dr Cyriac Abby Philips, a Kochi hepatologist known online as “The Liver Doc,” who has made a name debunking pseudoscience.
His points are specific. The study began with 219 patients but the final count was narrowed to 198. In the extract group, he said, the count of recovered patients held at 83 while the denominator fell from 146 to 129. By his arithmetic that moves the recovery rate from about 57% up to about 64%, though not one more person recovered. Some recovered placebo patients were also left out, he said. He further objected that the primary endpoint moved from platelet recovery by day 7, as registered, to day 4, which was meant as an interim check.
“If researchers decide after seeing the results what counts as the primary endpoint, they can almost always find a positive outcome by pure chance,” Philips said. A retired biostatistician agreed it was a “red flag.”
Funding drew questions as well. The pills came from Micro Labs, and the study had grants from Zydus Pharma and Lupin Pharma. Lupin markets the same extract as Caripapa. Ostwal said the researchers knew the funding sources but not that one funder sold the pills.
Where it stands
The journal later placed a temporary Expression of Concern on the article. The Tata Memorial team said it stands by every finding, that the study met the “highest standards of integrity,” and that no scientific queries had reached the investigators from the journal so far. The notice, they added, would be removed promptly if the issues proved unfounded.
Ostwal, for his part, says platelet counts in patients on the pills have steadily risen by about day 4. Dr Amar Jesani, a founder of the Indian Journal of Medical Ethics, suggested one way forward: release the raw, anonymised data.
Sources
- Papaya extract pills offer hope in chemo-induced platelet fall (Times of India)
- Tata Memorial stands by study on papaya-leaf extract's impact on platelet count in chemotherapy patients (BusinessLine)
- Tata Memorial Hospital's cancer study on papaya boosting platelets under lens (Times of India report, reprinted)
