Early Prostate Cancer Kept at Bay in 2 Studies for High-Risk Men

(Bloomberg) -- Men with an early form of prostate cancer who are at high risk of seeing it spread and turn deadly may benefit from treatment with Johnson & Johnson and Pfizer Inc. drugs that slow progression of the disease.

J&J’s experimental medicine apalutamide and Pfizer’s prostate cancer drug Xtandi delayed the worsening of the most common tumor by more than 70 percent compared with a placebo in two separate studies. The results, which are being presented at a medical meeting devoted to genital and urinary cancers in San Francisco, could offer an alternative for men whose cancer is progressing yet considered early-stage because localized to their prostate.

More than 164,000 men in the U.S. will be diagnosed with prostate cancer in 2018 and almost 30,000 will die from it, trailing only lung cancer in terms of mortality, according to the American Cancer Society. Right now patients with early disease typically undergo surgery, radiation and, if needed, treatment to deprive the tumor of testosterone that fuels its growth. But there is no approved follow-on therapy for those with worrisome blood test results who don’t yet have visible evidence that the prostate cancer has metastasized.

The situation has been agonizing for those men, who often are handled with what’s called “watchful waiting.” Many remain in limbo as levels of a protein tied to progression rises in their blood. With no clear evidence of the cancer in other parts of their bodies, they can’t be treated with drugs that are approved only for later stages of cancer.

“These patients can have a poor prognosis, and until now, the optimal management of their cancer remained an enigma,” said Sumanta Pal, co-director of the City of Hope’s kidney cancer program in Duarte, California, who reviewed the findings on behalf of the American Society of Clinical Oncology. “These findings suggest there may finally be a treatment that holds real promise for extending their health and their lives.”

‘Unmet Need’

J&J’s study, called Spartan, tracked 1,207 men with tumors that no longer responded to hormone therapy, known as castration-resistant prostate cancer, and show rapidly rising levels of prostate specific antigen in their blood. Men treated with J&J’s apalutamide went for 40 months, or 3.3 years, before the cancer metastasized, compared with 16 months in the placebo group.

“It’s a big unmet need,” said Eric Small, a professor of medicine at the University of California in San Francisco, who led the Spartan study. “Currently there is no approved standard of care.”

Xtandi, a drug made by Pfizer and Astellas Pharma Inc., is already the standard of care for advanced prostate cancer that doesn’t respond to hormone therapy and has spread, with more than 75,000 patients in the U.S. having been treated with it, according to Pfizer.

‘Catalyst for Change’

The new study being presented at the annual Genitourinary Cancers Symposium in San Francisco involved 1,400 patients with early stage prostate cancer. It found that men given Xtandi survived for a median of 36 months before the cancer spread, compared with 14.7 months for those given a placebo.

Doctors’ familiarity with the drug may speed earlier use of the medicine, Pal said in a conference call with reporters.

“This is going to be the catalyst for change,” Mace Rothenberg, Pfizer’s chief development officer for oncology, said in a telephone interview. “This is going to provide a much stronger foundation and rationale and level of evidence for treating men in this situation with Xtandi than has previously existed.”

Xtandi, which costs more than $10,000 for a 30-day supply, is projected by analysts to reach $1 billion in sales in 2020 for New York-based Pfizer.

There are about 65,000 men in the U.S. living with non-metastatic prostate cancer that doesn’t respond to hormone therapy and about 20,000 patients are diagnosed each year.

Overall, the cancer death rate in the U.S., including for that of prostate cancer, is declining, according to a new report by the American Cancer Society. That’s partly because of the improvements made to care and treatment, Rothenberg said.

The companies have requested approval for both drugs from the U.S. Food and Drug Administration as well as the European Medical Association.

To contact the reporters on this story: Michelle Fay Cortez in Minneapolis at mcortez@bloomberg.net, Jared S. Hopkins in New York at jhopkins38@bloomberg.net.

To contact the editors responsible for this story: Cecile Daurat at cdaurat@bloomberg.net, Timothy Annett

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