Sermonix Pharmaceuticals Announces Chinese Approval of Investigational New Drug Application for Lasofoxifene

• IND approval in China allows Shanghai Henlius Biotech, Sermonix’s Chinese development partner for oral lasofoxifene, to enroll ELAINE-3 trial patients in China
• Under strategic collaboration agreement signed in January, Henlius received exclusive rights from Sermonix to develop, manufacture and commercialize oral lasofoxifene in China
• Sermonix and Henlius will engage with PMDA and collaborate on expedited co-development of oral lasofoxifene in Japan

COLUMBUS, Ohio, June 06, 2024 (GLOBE NEWSWIRE) — Sermonix Pharmaceuticals Inc., a privately held biopharmaceutical company developing innovative therapeutics to specifically treat metastatic breast cancers (mBC), today announced that China’s National Medical Products Administration (NMPA) approved the investigational new drug application (IND) for oral lasofoxifene (HLX78 in China) submitted with the assistance of Chinese development partner Shanghai Henlius Biotech, Inc. (2696.HK).

The IND approval allows Henlius to join the ongoing global registrational ELAINE-3 trial with responsibility in China. ELAINE-3 (NCT05696626), the third Evaluation of Lasofoxifene in ESR1 Mutations (ELAINE) trial, is assessing the efficacy of oral lasofoxifene and Eli Lilly and Company’s CDK4/6 inhibitor abemaciclib (Verzenio^®) compared to fulvestrant and abemaciclib in 400 pre- and post-menopausal subjects with locally advanced or metastatic ER+/HER2- breast cancer with an ESR1 mutation.

This month, Henlius expanded its license from Sermonix to add additional Asia territories for upfront, milestone and royalty payments. The agreement also allows Henlius to share with Sermonix expedited co-development of oral lasofoxifene in Japan. Sermonix has completed a Phase 1 Japanese PK study and, together with Henlius, will begin engagement with the Pharmaceuticals and Medical Devices Agency (PMDA) to address a regulatory path to study lasofoxifene in Japan, which is an important region for expanded global access to lasofoxifene investigation.

“With active ELAINE-3 enrollment already underway in the U.S., Canada, EU and Israel, we are pleased to announce that Henlius, our Chinese development partner for oral lasofoxifene, received approval for its investigational new drug application,” said Dr. David Portman, Sermonix founder and chief executive officer. “This milestone clears Henlius to enroll patients in ELAINE-3 in China, therefore further diversifying our patient population and potentially helping more people to better confront this terrible disease.”

“The collaboration between Henlius and Sermonix started in January 2024,” said Ms. Ping Cao, Henlius chief business development officer and SVP of business development. “In mere months from agreement to amendment, our unified dedication shines, turning swift collaboration and full-hearted implementation into tangible success – as underscored by our product’s IND approval in China.”

Oral lasofoxifene is an investigational novel targeted endocrine therapy in clinical development that has demonstrated robust target engagement as an ESR1 antagonist in the breast, particularly in the presence of ESR1 mutations.

In two completed Phase 2 clinical studies (ELAINE-1 and ELAINE-2), lasofoxifene demonstrated anti-tumor activity against tumors with ESR1 mutations as a monotherapy and in combination with abemaciclib, a CDK4/6 inhibitor. Lasofoxifene’s bioavailability and potent activity in mutations of the estrogen receptor, in addition to its potential to improve sexual and urogenital health with a well-tolerated profile, could hold promise for patients who have acquired endocrine resistance due to ESR1 mutations, and, if approved, play a critical role in the precision medicine treatment of advanced ER+ breast cancer.

Breast cancer is the second most diagnosed cancer in the world, according to GLOBOCAN 2022. There were around 2.3 million new cases of breast cancer in 2022 globally, including more than 357,000 in China.¹ ER+ breast cancer comprises 60-70% of all breast cancers.² Endocrine therapy remains the mainstay treatment for ER+ breast cancer and the most widely used class of aromatase inhibitor (AI) has been recommended by the National Comprehensive Cancer Network (NCCN) and Chinese Society of Clinical Oncology (CSCO) guidelines to be the adjuvant and first-line standard of care for patients with ER+/HER2- breast cancer.^3,4 However, almost all patients treated with AIs in the advanced setting develop resistance,⁵ with ESR1 mutations being one of the most prevalent alterations, present in up to 40% of patients and a significant mechanism of resistance to endocrine therapy.⁶ Currently, there are limited treatment options for ER+/HER2- breast cancer with ESR1 mutations, and thus a large clinical need exists.

[1] Sung H, Ferlay J, Siegel RL, Laversanne M, Soerjomataram I, Jemal A, Bray F. Global Cancer Statistics 2020: GLOBOCAN Estimates of Incidence and MortalityWorldwide for 36 Cancers in 185 Countries. CA Cancer J Clin. 2021 May;71(3):209-249.
[2] Ignatiadis M, Sotiriou C. Luminal breast cancer: from biology to treatment[J]. Nat Rev Clin Oncol, 2013, 10(9): 494-506. doi: 10.1038/nrclinonc.2013.124.
[3] Chinese Society of Clinical Oncology (CSCO) Breast Cancer Guidelines 2023
[4] NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines®) for Breast Cancer V.5.2023
[5] Rozeboom B, Dey N, De P. ER+ metastatic breast cancer: past, present, and a prescription for an apoptosis-targeted future. Am J Cancer Res. 2019;9(12):2821-2831. Published 2019 Dec 1.
[6] Spoerke JM, Gendreau S, Walter K, et al. Heterogeneity and clinical significance of ESR1 mutations in ER-positive metastatic breast cancer patients receiving fulvestrant. Nat Commun. 2016;7:11579. Published 2016 May 13. doi:10.1038/ncomms11579

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 3 clinical study of lasofoxifene, its lead investigational drug. The Sermonix management team, led by founder Dr. David Portman, has significant experience in all stages of the drug development, regulatory and commercialization processes. Paul Plourde, M.D., vice president of oncology clinical development, has many decades of experience at AstraZeneca in the breast cancer drug development arena. Barry Komm, Ph.D., chief scientific officer, is recognized for his expertise in nuclear receptor biology. Miriam Portman, M.D., is co-founder and chief operating officer, with expertise in clinical trial conduct and patient recruitment. 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. To learn more about Sermonix, visit SermonixPharma.com. To learn more about the ELAINE studies, visit DiscoverElaine.com.

About Henlius
Henlius (2696.HK) is a global biopharmaceutical company with the vision to offer high-quality, affordable, and innovative biologic medicines for patients worldwide with a focus on oncology, autoimmune diseases, and ophthalmic diseases. Up to date, 5 products have been launched in China, 3 have been approved for marketing in overseas markets, 23 indications are approved worldwide, and 3 marketing applications have been accepted for review in China and the EU, respectively. Since its inception in 2010, Henlius has built an integrated biopharmaceutical platform with core capabilities of high-efficiency and innovation embedded throughout the whole product life cycle including R&D, manufacturing and commercialization. It has established global innovation centre and Shanghai-based commercial manufacturing facilities certificated by China, the EU and U.S. GMP.