Endo International plc announced that its subsidiary Endo Ventures Limited (EVL) has executed an agreement with Taiwan Liposome Company, Ltd. (TLC), a clinical-stage specialty pharmaceutical company developing novel nanomedicines to target areas of unmet medical need, to commercialize TLC599, a TLC investigational product. TLC599 is an injectable compound in Phase 3 development for the treatment of osteoarthritis knee pain. Endo currently expects to launch the differentiated branded product in the United States in 2025.

Under the terms of the agreement, TLC will primarily be responsible for the development of the product and EVL will primarily be responsible for obtaining regulatory approval and commercialization of the product in the United States. Upon receipt of regulatory approval, Endo will have exclusive rights to manufacture, market, sell and distribute the product in the United States. TLC will receive an upfront payment of $30 million and will be eligible to receive up to an additional $110 million based on the achievement of certain development, regulatory, and manufacturing milestones related to the initial indication for the treatment of osteoarthritis knee pain.

TLC will be eligible to receive payments based on the achievement of certain commercial milestones and royalties based on the product's net sales in the United States. Additionally, TLC will be eligible to receive certain milestone payments for potential future indications. The upfront payment of $30 million will be expensed in the second quarter as acquired in-process research and development.

This expense was not reflected in Endo's second quarter 2022 financial guidance provided on May 5, 2022 as the transaction was signed after the date of the second quarter earnings release. TLC 599 is an extended and controlled release liposomal formulated dexamethasone for chronic knee osteoarthritis (OA) pain. Single and repeated doses of current intraarticular anti-inflammatory treatments for OA have potentially toxic side effects and may lead to the destruction of cartilage filler proteins.

Preclinical toxicity studies showed no marked cartilage damage after single and multiple doses of TLC599 when compared to current treatments. In a Phase II clinical trial, a single injection of TLC599 resulted in statistically significant and clinically meaningful improvement in WOMAC Pain and Function Subscales, and VAS Pain scores over placebo at 12, 16 and 24 weeks. Over half of the patients in the TLC599 group had a durable response, maintaining at least 30% pain reduction in both WOMAC and VAS pain scores at all visits through the 24 weeks.

No serious or unexpected treatment related adverse events were reported, and most of the treatment related adverse events were mild to moderate in severity. EXCELLENCE, a pivotal Phase III clinical trial to evaluate the efficacy and safety of both single and repeated doses of TLC599, is nearing completion, with the last patient's last visit having taken place in January 2022. The compound may be investigated in the future for additional potential indications.