On December 8, 2016 Radius Health, Inc. (Nasdaq:RDUS), a science-driven biopharmaceutical company focused on developing innovative therapeutics in the areas of osteoporosis, oncology and endocrine diseases, reported data from two ongoing Phase 1 studies of RAD1901, an oral selective estrogen receptor degrader (SERD), in patients with estrogen receptor positive (ER+) breast cancer, which were presented this morning at the San Antonio Breast Cancer Symposium 2016 (Press release, Radius, DEC 8, 2016, View Source [SID1234517005]).

Schedule your 30 min Free 1stOncology Demo!
Discover why more than 1,500 members use 1stOncology™ to excel in:

Early/Late Stage Pipeline Development - Target Scouting - Clinical Biomarkers - Indication Selection & Expansion - BD&L Contacts - Conference Reports - Combinatorial Drug Settings - Companion Diagnostics - Drug Repositioning - First-in-class Analysis - Competitive Analysis - Deals & Licensing

                  Schedule Your 30 min Free Demo!

As of the cut-off date of October 7, 2016, 20 patients have been treated in the RAD1901 Phase IB safety expansion cohort at the 400 mg dose. These patients are heavily pretreated ER+, HER2-negative advanced breast cancer patients who have received a median of 3 prior lines of therapy. Of the enrolled patients, 19 out of 20 had measurable disease at baseline and there were two confirmed partial responses by RECIST criteria. Across the Part A dose escalation (n=13) and safety expansion cohort (n=20), 14 patients were on study drug for greater than or equal to 4 months, 5 patients for greater than or equal to 6 months, and 7 patients remained on study drug. RAD1901 was well-tolerated with the most common adverse events being low grade nausea and dyspepsia.

In the ongoing European Phase I RAD1901 FES-PET trial, the first three-patients were enrolled at 400 mg as of the October 7th cut-off date and achieved a reduction in 18F-FES uptake ranging from 79%-91% at day 14 compared to baseline. One patient had a confirmed partial response by RECIST criteria. All three patients remained on study drug with mean duration of treatment of 5.64 cycles. Adverse events reported to date have been grade 1 and 2 and manageable. This study will enroll 5 additional patients in the 400 mg QD cohort followed by 8 patients in the 200 mg QD cohort. No dose limiting toxicities have been reported across any of the studies in the RAD1901 program.

"The single-agent clinical activity and duration of response demonstrated with RAD1901 in the heavily pretreated population may be important in addressing the major challenge of resistance facing patients with ER positive advanced breast cancer," said Dr. Virginia Kaklamani, Professor of Medicine, UT Health Science Center San Antonio, leader of the Breast Cancer Program, Cancer Therapy & Research Center, and investigator on the study.

"An oral, well-tolerated and effective SERD could become an important adjunct in combination therapy for patients and we look forward to the results of additional studies," said Professor George W. Sledge Jr., Professor and Chief of Medical Oncology at Stanford University Medical Center, and member of Radius’ Oncology Clinical Advisory Board.

Dr. Virginia Kaklamani and Dr. George Sledge will participate in a Radius hosted investor meeting and webcast later today to highlight the RAD1901 data presented at SABCS at 8 p.m. CT. The webcast and a replay can be accessed on the company’s website, www.radiuspharm.com.

The posters presented this morning from the RAD1901 clinical development program were:

Abstract Title: A Phase 1 Study of RAD1901, a Novel, Oral, Selective Estrogen Receptor Degrader, for the Treatment of ER-Positive Advanced Breast Cancer, Poster # 1454

Abstract Title: A Phase 1 Study of RAD1901, an Oral Selective Estrogen Receptor Degrader, to Determine Changes in the F-FES Uptake and Tumor Responses in ER-Positive, HER-2-Negative, Advanced Breast Cancer Patients, Poster # 1604

Radius will also present later the following poster later today from the RAD1901 preclinical program:

Abstract Title: RAD1901 Demonstrates Anti-Tumor Activity in Multiple Models of ER-Positive Breast Cancer Treatment Resistance, Poster # 1378
Poster Session 3
Session Title: Tumor Cell and Molecular Biology: Endocrine Therapy and Resistance
Session Date: 12/8/2016
Session Time: 5:00 PM — 7:00 PM
Location: Hall 1