FRIDAY, March 22, 2024 (HealthDay News) -- An already approved cancer drug could be an effective treatment for women with advanced, recurring uterine cancer, a new clinical trial shows.

Rucaparib, which belongs to a class of drugs called PARP inhibitors, extended women’s survival for more than a year and a half, on average, compared to simple surveillance following chemotherapy, researchers report.

“We improved patients’ progression-free survival, meaning time without recurrence or progression, by an average of 19 months,” said lead researcher Dr. Bradley Corr, an oncologist with the University of Colorado Cancer Center.

“Patients on placebo had a progression-free survival of nine months, whereas it was 28 months for those who had received rucaparib,” Corr added in a university news release. “This is very significant for our patients and for their care.”

Rucaparib currently is approved to treat breast, ovarian and prostate cancer, Corr said.

PARP inhibitors work by blocking naturally occurring enzymes that help damaged cells repair themselves. Unfortunately, these enzymes also help cancer cells recover from damage done by chemotherapy.

Uterine cancer, also known as endometrial cancer, affects more than 60,000 women in the United States each year, and is one of the few cancers in which cases are increasing, researchers said in background notes.

Survival for early-stage uterine cancer is high, at more than 80%, but survival rates decrease dramatically in advanced cases, the researchers said.

In the clinical trial, all patients underwent one or two courses of chemotherapy, and then half were randomly assigned to take rucaparib, which comes in pill form.

Currently, the only treatment option for uterine cancer patients following chemotherapy is to watch and wait, in hopes their cancer won’t return, researchers said.

The unfortunate reality is that most late-stage uterine cancers eventually come back after chemo, Corr said.

These results show that rucaparib can extend the time before patients’ cancer returns, Corr said.

Researchers suspect rucaparib works against uterine cancer because it blocks off DNA damage repair pathways.

For their next step, Corr and his team will analyze the tumors and patients, to better identify who most benefitted from treatment with the drug.

The findings were presented this week at the Society of Gynecologic Oncologists annual meeting in San Diego. Such research is typically considered preliminary until published in a peer-reviewed journal.

More information

Cancer Research UK has more about PARP inhibitors.

SOURCE: University of Colorado, news release, March 20, 2024