On January 12, 2024 Windtree Therapeutics, Inc. entered into a License, Development and Commercialization Agreement with Lee?s Pharmaceutical (HK) Ltd., effective as of January 7, 2023 (the ? Lee ? s License Agreement?).

Under the Lee?s License Agreement, the Company granted to Lee?s an exclusive license, with a right to sublicense, to develop, register, make, use, sell, offer for sale, import, distribute and otherwise commercialize products that incorporate istaroxime for intravenous administration, rostafuroxin for oral administration, and the Company?s proprietary dual-mechanism SERCA2a activators for intravenous or oral administration (collectively, the ? Products? and each, a ?

Product?), in each case for the prevention, mitigation and/or treatment of any disease, disorder or condition in humans including acute decompensated heart failure, cardiogenic shock, and chronic use following discharge of an individual hospitalized for acute decompensated heart failure (? Field?) in the People?s Republic of China, Hong Kong, Macau, Taiwan, Singapore, South Korea, Thailand, Vietnam, Brunei, Myanmar, Cambodia, East Timor, Indonesia, Laos, Malaysia, and the Philippines (the ? Licensed Territory?).

Under the Lee?s License Agreement, the Company may receive up to $3.1 million in potential upfront pre-development, development, clinical, and regulatory milestone payments and up to $135.25 million in sales milestone payments. The Company is also entitled to receive a low double-digit percentage of Lee?s non-royalty sublicense income. The Company is eligible to receive tiered royalties based on a percentage of Net Sales (as defined in the Lee?s License Agreement) that ranges from low single-digit to low double-digit percentages, depending on the Product.

Royalties are payable on a Product-by-Product and country-by-country basis until the latest of (A) the expiration of the last valid patent claim covering the Product in the country of sale, (B) the expiration or revocation of any applicable regulatory exclusivity in the country of sale, and (C) ten (10) years after the first commercial sale of the Product in the country of sale. Thereafter, in consideration of licensed rights other than patent rights, royalties shall continue for the commercial life of each Product but at substantially reduced rates. In addition, the royalty rates are subject to reduction by as much as 50% in a given country based on generic competition in such country.

Under the Lee?s License Agreement, Lee?s will be solely and exclusively responsible for all costs and activities related to the development, manufacturing, regulatory approval and commercialization of Products in the Licensed Territory, with the exception of certain costs in connection with filing fees payable to regulatory authorities in the Licensed Territory relative to a Product for which the Company holds the applicable marketing authorization. Lee?s may sublicense its rights to its affiliates and may grant sublicenses to third-party subcontractors to perform certain activities under the Lee?s License Agreement on behalf of Lee?s or its affiliates but may not otherwise grant sublicenses to unaffiliated third parties without the prior consent of the Company. A sublicensee and a subcontractor may not be a competitor identified by the Company.

Sublicenses granted under the Lee?s License Agreement may not include the right to further sublicense. The Lee?s License Agreement establishes a joint steering committee and a joint development committee to oversee the regional development (with the Company retaining final decision rights over clinical protocols) and a joint commercialization committee.