Hey Rman,
A belated welcome back. Been busy with non-biotech related stocks. Just wanted to say welcome back to you and hi to all my friends here and to spread the good LGND news:
Targretin(TM) Causes Complete Regression Preclinically in 72% of Breast Cancer Tumors
Study in Animal Model Demonstrates Targretin More Effective Than Tamoxifen;
Ligand Evaluates Phase II Clinical Trials for Breast Cancer
SAN DIEGO, Feb. 11 /PRNewswire/ -- Targretin(TM) (LGD 1069), a member of an increasingly important new class of drugs called retinoids, caused complete regression in 72 percent of established breast cancer tumors in one of the most commonly used rat models of this disease, according to a study published by scientists from Ligand (LYE-gand) Pharmaceuticals Inc. (Nasdaq: LGND) in the current issue of Cancer Research.
Previous research (Cancer Research, December 1996) demonstrated that Targretin (tar-GRET-in) is equally as effective as tamoxifen at preventing the emergence of breast cancer tumors in this animal model, which was designed to test prevention. The current study is the first to compare the treatment potential of Targretin and tamoxifen both individually and in combination therapy. The use of tamoxifen alone resulted in complete regression in 33.3 percent of tumors, compared to Targretin's rate of regression in 72 percent of tumors. Tamoxifen is currently the most widely prescribed breast cancer therapy.
"We are particularly pleased with these exciting results in established tumors and the implications for the treatment of breast cancer. These findings build on Ligand's previous studies that focused on breast cancer prevention, and we now have determined that Targretin is effective in the treatment of well-established tumors," according to Richard Heyman, Ph.D., Senior Director of Ligand's department of Retinoid Research.
Targretin is a synthetic retinoid analogue discovered by Ligand scientists which selectively activates a subclass of retinoid receptors called retinoid X receptors (RXRs) which play an important role in cellular activities.
In the placebo controlled study, one group of animals with established tumors was randomized to receive Targretin, one group received placebo, and a third group received tamoxifen. Animals administered Targretin received an oral dose of 10, 30, or 100 mg/kg, and animals administered tamoxifen received subcutaneous injections of 150 or 800 micrograms/kg.
Additional evaluation of animals receiving low doses of both Targretin (10 mg/kg,) and tamoxifen (150 micrograms/kg) showed that tamoxifen efficacy was enhanced substantially when given in combination with Targretin. Tissue analysis of the Targretin-treated tumors showed a reduction of tumor malignancy, an increase in cellular differentiation and a sharp decrease in cellular proliferation.
"These data reinforce the role this new class of retinoids may have in breast cancer treatment, particularly in combination with proven treatments like tamoxifen," said Michael Sporn, M.D., professor of Pharmacology and Medicine, Dartmouth Medical School.
Ligand scientists have previously reported that Targretin does not alter estrogen, progesterone, or prolactin levels in this scientific model, and that Targretin can inhibit the uterine cell growth stimulation by estrogen and tamoxifen.
"The ability of Targretin to cause tumor regression in an animal model of established tumors provides a strong basis for a clinical trial in advanced breast cancer," said Steven Reich, M.D., Ligand Vice President of Clinical Research. "The additional activity of the combination of tamoxifen and Targretin is important because so many women with breast cancer are receiving tamoxifen. We are currently reevaluating our Phase II clinical trial options with Targretin in breast cancer given these exciting preclinical findings."
Ligand is conducting three pivotal trials for the treatment of patients with cutaneous T-cell lymphoma, including one Phase III trial with Targretin Gel and two Phase II/III trials with Targretin Capsules; Phase II/III trials with Targretin Capsules in patients with advanced lung cancer; Phase IIb studies for ovarian, head and neck cancer and Kaposi's sarcoma; and Phase II trials with Targretin Gel for the treatment of actinic keratosis.
Since 1989, Ligand Pharmaceuticals Incorporated has established a leadership position in gene transcription technology, particularly intracellular receptor (IR) technology and Signal Transducers and Activators of Transcription (STATs). Ligand has applied IR and STATs technology to the discovery and development of small molecule drugs to enhance therapeutic and safety profiles and to address unmet patient needs in cancer, women's and men's health and skin diseases, as well as osteoporosis, metabolic, cardiovascular and inflammatory disease.
SOURCE Ligand Pharmaceuticals Inc. |
