Why Prolia May Be The Better Drug For Reducing Bone Breaks And Recurrence After Breast Cancer

“As people age, the risk of fracturing a bone – whether it’s a hip, a wrist, vertebrae, an ankle or toe, climbs steadily. For women and men who live after a cancer diagnosis, the risk of breaking bone is greater.

“At this year’s San Antonio Breast Cancer Symposium, Dr. Michael Gnant of Vienna gave an update on a major trial of denosumab in its capacity to reduce fractures and possibly stave off metastases. This drug is manufactured and sold by Amgen in a low-dose form as Prolia. Prolia is a monoclonal antibody that doesn’t require intravenous administration; it’s injected under the skin, just twice each year.

“The ongoing trial, by the Austrian Breast and Colorectal Cancer Study Group (ABCSG), includes over 3,400 postmenopausal women with non-metastatic, hormone receptor positive breast cancer. All participants took an aromatase inhibitor, a standard treatment given to lower hormone levels, and were randomized to receive either low-dose (60 milligrams) denosumab or a placebo injection under the skin, twice yearly.”

Bone Drugs Equal as Breast Cancer Therapies

“One bone-preserving drug is as good as another in early stage breast cancer, a researcher said here.

“In a large randomized trial, there were few differences in anti-cancer efficacy among three different members of the bisphosphonate class, according to Julie Gralow, MD, of the University of Washington in Seattle.

“And the overall safety of the drugs was also similar, Gralow reported at the annual meeting of the American Society of Clinical Oncology.

“But the study might not help settle a continuing controversy in oncology over the use of the drugs, which normally are prescribed to slow bone embrittlement by inhibiting the action of osteoclasts.”

Osteoporosis Drugs Might Help Prevent, Treat Cancers with HER Gene Abnormalities

The gist: New research shows that drugs used to treat osteoporosis might help prevent or treat certain types of lung, breast, and colorectal cancer. These drugs, called bisphosophonates, might work against tumors that have abnormalities in the HER gene.

“Researchers have discovered that bisphosphonates inactivate human epidermal growth factor (EGF) receptors to exert antitumor effects, and they say the widely prescribed osteoporosis drugs may prove to be a cheap and useful adjuvant to current therapies for HER-driven cancers.

“Bisphosphonates directly bind to and inhibit HER kinases, including commonly mutated forms that drive non-small-cell lung cancer and other cancer growth and resistance to tyrosine kinase inhibitors, according to two studies published online this week in the journal PNAS Early Edition, by researcher Mone Zaidi, MD, of Mount Sinai School of Medicine, in New York City, and colleagues.

“If the findings are confirmed, bisphosphonates could potentially be repurposed for the prevention and adjuvant treatment of breast, lung, and colorectal cancers that are driven by HER (human EGF receptor), the researchers wrote.

” ‘There is quite a lot of anecdotal literature as well as a few clinical epidemiologic studies suggesting that women who take bisphosphonates (for osteoporosis) have a lower risk for breast and colorectal cancer,’ Zaidi told MedPage Today.

“He added that several studies of cancer patients treated with intravenous bisphosphonates for bone metastasis suggest the drugs have positive effects on tumor cell burden.”

Too Few Prostate Cancer Patients Get Bone-Strengthening Meds: Study

“Many men on hormone therapy for prostate cancer aren’t getting bone-strengthening drugs they may need, new Canadian research contends.

“Hormone therapy, which suppresses male hormones called androgens, helps stop cancer cells from growing. But one consequence of the treatment is weakening of the bones, which can lead to fractures. To reduce this risk, men can be given oral bisphosphonates, such as Fosamax, or an intravenous treatment once a month or once a year with similar drugs, such as Reclast.

” ‘There seems to be a clear mismatch between Canadian guidelines regarding bisphosphonate usage in men undergoing hormone therapy for prostate cancer and actual clinical practice,’ said lead researcher Dr. Shabbir Alibhai, a senior scientist at the University Health Network in Toronto.

“While the low rates of bisphosphonate prescriptions may be appropriate for patients who are at low risk for fracture, most men with osteoporosis or other bone conditions should be taking a bisphosphonate, he said.”

Radium-223 Dichloride Effective in CRPC, Regardless of Prior Docetaxel

The gist: The drug Xofigo (aka radium-223 dichloride) is often used to treat bone metastases in patients with castration-resistant prostate cancer. New research results show that it is safe and effective for these patients whether or not they have previously been treated with the chemotherapy drug docetaxel.

“Radium Ra 223 dichloride appeared safe and effective in patients with castration-resistant prostate cancer and symptomatic bone metastases regardless of whether they received prior docetaxel, according to a subgroup analysis from a randomized phase 3 trial.

“Results of the ALSYMPCA showed radium Ra 223 dichloride [radium-223 (Xofigo, Bayer)], a targeted alpha-emitter, extended OS compared with placebo in patients with castration-resistant prostate cancer and symptomatic bone metastases. The agent also appeared well tolerated.

“Researchers established prior docetaxel treatment as a trial stratification factor.

“In the prespecified subgroup analysis, researchers sought to assess the effect of prior docetaxel treatment on efficacy and safety outcomes.”