Sermonix Pharmaceuticals to Collaborate With Eli Lilly and Company in Studying Combination of Lasofoxifene and Lilly’s CDK 4 and 6 Inhibitor, Abemaciclib, in Metastatic Breast Cancer

The multicenter Phase 2 trial, Sermonix’s Evaluation of Lasofoxifene and Abemaciclib in ESR1 Mutations, is projected to begin enrollment in Q3 2020.

COLUMBUS, Ohio (July 8, 2020) — Sermonix Pharmaceuticals Inc., a privately held biopharmaceutical company focused on the development of female oncology products in the precision medicine metastatic breast cancer arena, today announced a collaboration with Eli Lilly and Company to study Sermonix’s lead investigational drug, lasofoxifene, in combination with Lilly’s FDA-approved CDK 4 and 6 inhibitor, abemaciclib.

The open-label, multi-center Phase 2 clinical trial, which is projected to begin enrollment in the third quarter of 2020, will evaluate the safety of lasofoxifene in combination with abemaciclib for the treatment of pre- and postmenopausal women with locally advanced metastatic estrogen receptor-positive (ER+)/HER2- breast cancer and an ESR1 mutation. It marks Sermonix’s second Evaluation of Lasofoxifene in ESR1 Mutations (ELAINE) study and will be known as ELAINE 2.

“Sermonix is pleased to begin studying our lead compound, lasofoxifene, in collaboration with Lilly for pretreated patients with advanced breast cancer harboring an ESR1 mutation,” said Dr. David Portman, founder and chief executive officer of Sermonix Pharmaceuticals. “We look forward to learning more about the safety of this combination to further support a larger study.”

Preclinical models of invasive breast cancer at the University of Chicago have identified synergy between lasofoxifene, a selective estrogen receptor modulator (SERM), and a CDK 4 and 6 inhibitor, palbocicilib, in the presence of ESR1 mutations.

“It is exciting to see this Sermonix combination study with Lilly’s abemaciclib, as it will investigate lasofoxifene paired with an already-approved therapy used widely to treat patients with metastatic breast cancer,” said Dr. Geoffrey Greene, Ph.D., chair of the Ben May Department for Cancer Research at the University of Chicago and a member of Sermonix’s Oncology Steering Committee. “We recently presented preclinical data at the American Association for Cancer Research, demonstrating lasofoxifene synergy with a CDK 4 and 6 inhibitor, palbocicilib. The ELAINE 2 study is an important first step in looking at a combination in the clinic.”

ELAINE 1, which is currently enrolling patients, is a Phase 2 clinical trial assessing the efficacy of oral lasofoxifene versus intramuscular fulvestrant for the treatment of postmenopausal women with locally advanced or metastatic ER+/HER2- breast cancer with an ESR1 mutation as identified by a liquid biopsy and progression-free survival as the primary endpoint. The open-label, randomized, multi-center study (NCT03781063) is being conducted at multiple sites in the U.S., Canada and Israel.

“Endocrine therapy is the backbone of combination therapies in ER+/HER2- breast cancer, and as a well-characterized compound, lasofoxifene may offer patients a potentially well-tolerated oral option alone and in combination in an area of significant unmet need,” said Sermonix Board Chairman Dr. Anthony Wild. “We look forward to embarking on ELAINE 2 and executing on this important trial.”

About Lasofoxifene

Lasofoxifene is an investigational, nonsteroidal selective estrogen receptor modulator (SERM), which Sermonix licensed globally from Ligand Pharmaceuticals Inc. (NASDAQ: LGND) and has been studied in previous comprehensive Phase 1-3 non-oncology clinical trials in more than 15,000 postmenopausal women worldwide. Lasofoxifene’s bioavailability and activity in mutations of the estrogen receptor could potentially hold promise for patients who have acquired endocrine resistance due to ESR1 mutations, a common finding in the metastatic setting and an area of high unmet medical need. Lasofoxifene’s novel activity in ESR1 mutations was discovered at Duke University and Sermonix has exclusive rights to develop and commercialize the product in this area. Lasofoxifene, a potent, oral SERM could, if approved, play a critical role in the targeted precision medicine treatment of advanced ER+ breast cancer.

About Abemaciclib

Abemaciclib (trade name Verzenio®) is a CDK4 and 6 inhibitor and the first and only oral tablet of its kind that can be taken every day for the treatment of HR+, HER2– metastatic breast cancer. It is indicated for the treatment of HR+, HER2- advanced or metastatic breast cancer, in combination with an aromatase inhibitor for postmenopausal women as initial endocrine-based therapy; in combination with fulvestrant for women with disease progression following endocrine therapy; or as a single agent for adult patients with disease progression following endocrine therapy and prior chemotherapy in the metastatic setting.

About Sermonix

Sermonix Pharmaceuticals Inc. is a privately held biopharmaceutical company focused on the development of female-specific oncology products and is currently undertaking a Phase 2 clinical study of lasofoxifene, its lead investigational drug. Sermonix Pharmaceuticals was founded in 2014 by David Portman, M.D., a leading clinical researcher and expert in women’s health, menopause and selective estrogen receptor modulator (SERM) therapy. The Sermonix management team, led by Dr. Portman, has significant experience in all stages of the drug development and regulatory process. Paul Plourde, M.D., vice president of oncology clinical development, has many decades of experience in the oncology drug development arena. Barry Komm, Ph.D., chief scientific officer, is recognized for his expertise in SERM biology. Elizabeth Attias, M.M.Sc., Sc.D., chief strategy and development officer, has extensive experience in pharmaceutical drug commercialization. Simon Jenkins, Ph.D. vice president of operations, has over 30 years of experience in global drug development leadership. Sermonix non-executive chairman of the board is Anthony Wild, Ph.D., former president of both Parke-Davis Pharmaceuticals and Warner-Lambert’s Pharmaceutical Division. Learn more at https://sermonixpharma.com/