18 June 2021 - - Japan-based pharmaceutical company Eisai Co., Ltd. and US-based Bristol-Myers Squibb Company (NYSE: BMY) have entered into an exclusive global strategic collaboration agreement for the co-development and co-commercialization of MORAb-202, an antibody drug conjugate, the companies said.

MORAb-202 is Eisai's first ADC and combines Eisai's in house developed anti-folate receptor alpha antibody, and Eisai's anticancer agent eribulin, using an enzyme cleavable linker.

It is a potential best-in-class FRα ADC with a favorable pharmacology profile and demonstrated single agent activity in patients with advanced solid tumors.

Eisai is currently investigating MORAb-202 in FRα-positive solid tumors (inclusive of endometrial, ovarian, lung and breast cancers) in two studies: a Phase 1 clinical study in Japan and a Phase 1/2 clinical study in the United States.

The companies are planning to move into the registrational stage of development for this asset as early as next year.

Under the agreement, Eisai and Bristol Myers Squibb will jointly develop and commercialize MORAb-202 in the following collaboration territories: Japan; China; countries in the Asia-Pacific region; the United States; Canada; Europe, including the European Union and the United Kingdom; and Russia.

Bristol Myers Squibb will be solely responsible for developing and commercializing the drug in regions outside of the collaboration territories. Eisai will remain responsible for the manufacturing and supply of MORAb-202 globally.

Under the financial terms of the agreement, Bristol Myers Squibb will pay USD 650m to Eisai including USD 200m as payment toward Eisai research and development expenses.

Eisai is also entitled to receive up to USD 2.45bn in potential future development, regulatory, and commercial milestones.

The parties will share profits, research and development and commercialization costs in the collaboration territories and Bristol Myers Squibb will pay Eisai a royalty on sales outside of the collaboration territories.

Eisai is expected to book sales of MORAb-202 in Japan, China, countries in the Asia-Pacific region, Europe and Russia. Bristol Myers Squibb is expected to book sales of MORAb-202 in the United States and Canada.

Eisai is a global research and development-based pharmaceutical company headquartered in Japan, with approximately 10,000 employees worldwide.

Bristol Myers Squibb is a global biopharmaceutical company whose mission is to discover, develop and deliver innovative medicines that help patients prevail over serious diseases.

MORAb-202 is Eisai's first antibody drug conjugate that is composed of Eisai's in-house developed anticancer agent farletuzumab, a humanized IgG1 monoclonal antibody that binds to the folate receptor alpha, and Eisai's in-house developed anticancer agent eribulin, using an enzyme cleavable linker.

Eisai is currently conducting a Phase 1 clinical study in Japan and a Phase 1/2 clinical study in the United States, respectively, for MORAb-202 targeting FRα-positive solid tumors.

After MORAb-202 enters the target FRα-positive cancer cells, the linker is enzymatically cleaved, releasing eribulin from the antibody leading to its antitumor activity.

Furthermore, in non-clinical studies, MORAb-202 demonstrated a bystander effect, with antitumor activity on the FRα-negative cancer cells surrounding the FRα-positive cancer cells.

The payload eribulin (product name: Halaven) is the first in the halichondrin class of microtubule dynamics inhibitors with a novel mechanism of action.

Structurally eribulin is a simplified and synthetically produced version of halichondrin B, a natural product isolated from the marine sponge Halichondria okadai, and functions by inhibiting the growth phase of microtubule dynamics which prevents cell division.

Eribulin is currently approved for use in the treatment of breast cancer in over 75 countries worldwide, including Japan, the United States, Europe, China, and other countries in Asia.

Furthermore, eribulin is approved for use in the treatment of liposarcoma (soft tissue sarcoma in Japan) in over 75 countries worldwide, including Japan, the United States, as well as countries in Europe and Asia.