Bionovo describes a new class of therapeutic compounds

Dec 2 2007

Bionovo, Inc. has announced the publication of a groundbreaking paper in the journal Molecular and Cellular Endocrinology covering the isolation, identification and description of a pure chemical compound, liquiritigenin, which represents a new class of therapeutic compounds showing promise for the safe treatment of menopausal symptoms.

Liquiritigenin is an active ingredient in Bionovo's drug candidate, MF101, which just successfully completed a Phase 2 study, and is now being prepared for pivotal Phase 3 testing.

The paper, entitled "Liquiritigenin is a plant-derived highly selective estrogen receptor beta agonist" provides details of the selective transcriptional activation of liquiritigenin to the estrogen receptor beta, highlights the advantages of an estrogen receptor beta targeted drug and discusses the isolation and structural identification of the pure chemical compound from Bionovo's MF101.

In brief, the currently available estrogen therapies used to treat menopausal symptoms are non-selective to both of the two known estrogen receptors, alpha and beta. Because of this non-selectivity, all estrogens marketed to treat menopausal symptoms have the potential to cause elevated risks for breast and uterine cancers due to the proliferative effects on breast and uterine tissues mediated through the estrogen receptor alpha. Selective activation of the estrogen receptor beta, however, does not lead to proliferation of MCF-7 breast cancer cell lines or an increase for uterine cancer in mouse xenograph models. Bionovo is taking advantage of the differential effects caused by the two estrogen receptors on cancer formation by developing selective estrogen receptor beta drugs. The mechanism of action of MF101 as a selective estrogen receptor beta therapy may provide a safer, long-term alternative to treat menopausal symptoms.

"Our study findings show a pure chemical compound from MF101 that is selective to the estrogen receptor beta which could lead to multiple novel therapies for the treatment of common conditions such as menopausal hot flashes, vaginal dryness and osteoporosis," said Dale Leitman, M.D., Ph.D., Center for Reproductive Sciences, University of California, San Francisco, principal investigator of the study and member of Bionovo's Scientific Advisory Board. "Unlike any of the drugs we currently prescribe to women, MF101 and liquiritigenin are highly selective to the estrogen receptor beta, and from a mechanistic standpoint, they could be safer drugs to treat many symptoms of menopause."

"We are very pleased to have advanced our ability to characterize MF101 by isolating this chemical compound and this new discovery will significantly strengthen our intellectual property position for our lead compound," added Isaac Cohen, chairman and CEO of Bionovo. "Given the increasing population of women entering menopause, and the lack of safe and effective treatments for these women, we are excited to be on the forefront of developing more selective and safer alternative drugs for this enormous indication."

MF101 is an oral drug designed for the treatment of hot flashes and night sweats in peri-menopausal and menopausal women. MF101 is a novel estrogen receptor beta selective agonist and unlike currently available hormone therapies, does not activate the estrogen receptor alpha, known to be implicated in tumor formation. Two hundred and seventeen women were enrolled into a double-blind, placebo-controlled, randomized Phase 2 clinical trial under the directorship of Dr. Deborah Grady in early 2007. Trial results showed that MF101 10 grams/day was statistically superior to placebo at reducing hot flashes and was extremely well tolerated with no serious side effects.