Cosette Pharmaceuticals acquires Mayne Pharma Group for $430 million

NEW YORK: Cosette Pharmaceuticals, Inc., a U.S.-based pharmaceutical company, announced Thursday that it has entered into a definitive agreement to acquire all outstanding shares of Mayne Pharma Group Limited (ASX: MYX) for AUD $7.40 per share. The total consideration for the transaction is approximately USD $430 million.

The Boards of Directors of both companies have approved the transaction, and Mayne Pharma’s Board has unanimously recommended that its shareholders vote in favor of the deal. The acquisition is expected to close in the second quarter of 2025.

“This acquisition marks a transformational step for Cosette, adding patented, high-growth products to solidify our leadership in women’s health in the U.S. and expanding our reach globally,” said Apurva Saraf, President and CEO of Cosette Pharma.

“By combining Cosette’s strong portfolio with Mayne Pharma’s proven commercial expertise, the combined company will be well positioned to further invest in innovation, portfolio expansion and better serve our patients. We look forward to a timely closing and welcoming Mayne Pharma to the Cosette family.”

Shawn Patrick O’Brien, CEO of Mayne Pharma, added, “Joining the Cosette team amplifies our shared mission to improve lives through innovative and accessible women’s health and dermatology medicines. This transaction represents a unique opportunity for our employees, customers, and patients. Together, we will extend the reach of important therapies, drive innovation, and improve patient access.”

Transaction Rationale

– The acquisition strengthens Cosette’s dermatology and women’s health businesses by creating a leading pharmaceuticals company in these fields in the U.S. with a presence in international markets.

– Cosette will leverage its commercial and operational capabilities alongside Mayne Pharma’s strengths. The combined company will have two FDA-approved manufacturing sites in Lincolnton, North Carolina, and Salisbury, South Australia.

– The deal adds multiple sustainable and growing patent-protected products, including brands such as VYLEESI®, INTRAROSA®, NEXTSTELLIS®, and RHOFADE®.

Terms of the Transaction

The transaction, comprising the acquisition of 100% of Mayne Pharma’s outstanding shares through a scheme arrangement, is expected to close in the second quarter of 2025, subject to customary closing conditions and regulatory and shareholder approvals. The combined company will be privately held upon completion.

Cosette is being advised by Santander US Capital Markets LLC and UBS Investment Bank as financial advisers, with Ropes & Gray LLP and Corrs Chambers Westgarth as legal advisers. Mayne Pharma is being advised by Jefferies Australia as financial adviser, with Gilbert + Tobin and Arnold & Porter as legal advisers.