Lab tests on saliva from head and neck cancer patients showed large drops in HPV and two harmful bacteria, but no one has yet chewed the gum in a trial

A chewing gum made from lablab beans cut human papillomavirus (HPV) levels by 93 percent in saliva samples and 80 percent in oral rinse samples from head and neck cancer patients, according to University of Pennsylvania researchers. The study, published in Scientific Reports, tested gum extracts on patient samples in the lab rather than in people's mouths.

The work targets a growing problem. HPV causes about 70 percent of oropharyngeal cancers in the United States- cancers of the tonsils and base of the tongue, according to the CDC- and these cancers now outnumber cervical cancer as the most common HPV-linked cancer in the country.

The appeal is simplicity — a low-cost, plant-based gum that lowers viral load in the mouth could someday support treatment or reduce spread. But the study was published in February and highlighted again this month by ScienceDaily, and it remains an early laboratory result.

A Sugar-Binding Bean Protein That Clumps Viruses

Lablab beans, also called hyacinth beans, naturally contain FRIL, a lectin, or sugar-binding protein. Many viruses carry sugar-coated proteins on their outer surface, and FRIL grabs onto those sugars.

The result is a viral pileup. "If they are aggregated, they cannot" infect cells, lead researcher Henry Daniell of Penn Dental Medicine told WHYY, describing how clumped virus particles stick together and to the gum.

HPV detection in the study relied on an ELISA test aimed at the virus's L1 surface protein, Pharmacy Times reported. Daniell has said the goal is to lower circulating HPV in the mouth before the virus integrates into human cells' DNA, the step that can start cancerous changes, particularly with the high-risk type HPV-16.

Daniell's lab has tested FRIL gum before. In 2025, a clinical-grade version neutralized more than 95 percent of two influenza strains in laboratory tests and showed strong activity against herpes simplex viruses.

Strong Lab Numbers, but No One Has Chewed It Yet

The team collected saliva and oral rinse samples from patients with head and neck squamous cell carcinoma and exposed them to gum extracts. The bean gum alone sharply reduced detectable HPV.

The team then added protegrin, an antimicrobial peptide, to target two bacteria, Porphyromonas gingivalis and Fusobacterium nucleatum, that are linked to worse outcomes in oral cancer. A single dose of the engineered gum extract reduced both to nearly undetectable levels, while beneficial mouth bacteria were not affected. Radiation therapy, by contrast, can kill helpful bacteria and allow yeast to overgrow.

The limits are substantial — this was an ex vivo study, meaning extracts were mixed with samples outside the body. No one chewed the gum. The HPV test used an assay that detects several HPV types rather than only the high-risk strains that cause most throat cancers, according to Dr. Bicuspid's report on the paper. The study also did not measure whether lowering viral or bacterial levels improves cancer outcomes.

On its own, the bean extract did little against the bacteria and, at higher concentrations, appeared to encourage some bacterial growth, possibly because of sugars in the bean powder. That is why the protegrin version was needed. Daniell has disclosed a patent interest in plant-based oral drug delivery.

From Patient Saliva Samples to Clinical Trials

The researchers say the results justify human trials in two roles: as an add-on to existing cancer treatment, and as a preventive tool to reduce infection and transmission. Daniell said the findings "support the value of advancing these therapies to clinical trials," in a Penn statement.

Penn dentist Marc Henschel, a co-investigator, told WHYY that an HPV clinical trial at Penn Medicine could also explore whether the gum helps protect partners of people already diagnosed with HPV-related cancer. The trial still requires regulatory approval, and its design and enrollment have not been published.

Head and neck cancers make up roughly 3 to 4 percent of U.S. cancer diagnoses, and many are found late, when treatment is harder, and side effects are heavier. Daniell has noted that most recently approved cancer drugs have not greatly improved quality of life or five-year survival for these patients, which is part of why his team is pursuing a cheap, locally delivered option that could run alongside standard care.

Even if trials succeed, the gum would not replace the HPV vaccine, which prevents infection with the highest-risk HPV types in the first place.

Protection That Works Today

The CDC recommends HPV vaccination at ages 11 to 12, with catch-up vaccination through age 26, and some adults up to 45 may benefit after talking with a clinician. Not smoking and limiting alcohol also lower the risk of head and neck cancers.

Warning signs that deserve a doctor's or dentist's attention include a sore throat or hoarseness lasting more than two weeks, a lump in the neck, trouble swallowing or a mouth sore that does not heal. Most such symptoms are not cancer, but persistent ones should be checked.

This gum is not available as a treatment, and no store-bought gum offers the same protection. Readers interested in research participation can watch Penn Dental Medicine's announcements for trial details.

What Readers Want to Know

What did the study find? Lablab bean gum extracts cut HPV by 93 percent in saliva and 80 percent in oral rinse samples from cancer patients.

Did people chew the gum? No. The extracts were tested on patient samples in the lab.

How does FRIL work? It binds sugars on virus surfaces and clumps viral particles together so they cannot easily enter cells.

Can the gum prevent or treat throat cancer? There is no evidence yet. Clinical trials are needed.

How common is HPV-related throat cancer? HPV causes about 70 percent of U.S. oropharyngeal cancers, now the most common HPV-linked cancer in the country.

How can I lower my risk now? Get the HPV vaccine if eligible, avoid tobacco, limit alcohol, and see a clinician about persistent throat or mouth symptoms.