Cosette Pharmaceuticals to acquire Mayne Pharma in $430m deal, strengthening women’s health and dermatology portfolio

Cosette Pharmaceuticals has announced a definitive agreement to acquire Mayne Pharma Group Limited, a move that will significantly expand its presence in the women’s health market and dermatology industry growth sectors. The acquisition, valued at approximately USD $430 million, will see Cosette purchase all outstanding shares of Mayne Pharma at AUD$7.40 per share. This represents a substantial premium over Mayne Pharma’s previous stock valuation, with a 37% increase over its closing price prior to the announcement, and a 57% premium over its 180-day volume-weighted average price.

The transaction, which has been unanimously approved by the Boards of Directors of both companies, is expected to close in the second quarter of 2025, subject to regulatory and shareholder approvals. Following the acquisition, Cosette Pharmaceuticals will emerge as a dominant force in pharmaceutical acquisition news, particularly in specialty markets such as dermatology and women’s health, where demand for innovative therapies continues to grow.

What Does This Acquisition Mean for the Women’s Health and Dermatology Sectors?

With this acquisition, Cosette Pharmaceuticals aims to strengthen its portfolio of specialty treatments, utilizing Mayne Pharma’s established infrastructure and commercial expertise. The deal will allow Cosette to expand its footprint in key pharmaceutical markets, particularly in the U.S., while enhancing global patient access to essential dermatology and women’s health treatments.

Apurva Saraf, President and CEO of Cosette Pharmaceuticals, described the acquisition as a “transformational step” for the company. He highlighted that integrating Mayne Pharma’s high-growth, patent-protected products with Cosette’s existing offerings will solidify the company’s leadership position in the U.S. market. By leveraging Mayne Pharma’s proven commercial capabilities, the combined entity is expected to drive dermatology industry growth while expanding access to essential medications.

Mayne Pharma’s CEO, Shawn Patrick O’Brien, emphasized that the acquisition represents a pivotal moment for the company. He noted that Mayne Pharma has strategically expanded its portfolio in dermatology and women’s health while optimizing patient access through a refined U.S. commercial strategy. The merger, he said, aligns with the company’s commitment to innovation, allowing both companies to extend the reach of their therapies and enhance patient outcomes.

How Will the Acquisition Strengthen Cosette’s Product Portfolio?

The acquisition will significantly expand Cosette Pharmaceuticals’ commercial and operational capabilities. With Mayne Pharma’s extensive experience in dermatology and women’s health, the combined entity will be better positioned to serve a broader patient base. Cosette will gain access to an extensive lineup of patent-protected women’s health and dermatology treatments, including brands such as VYLEESI, INTRAROSA, NEXTSTELLIS, ANNOVERA, BIJUVA, IMVEXXY, and RHOFADE. These products represent some of the most innovative treatments in pharmaceutical acquisition news, particularly in areas of hormone therapy, contraception, and dermatological care.

Additionally, the acquisition will enable Cosette to enhance its manufacturing capabilities. The company will now operate two state-of-the-art, FDA-approved manufacturing facilities—one in Lincolnton, North Carolina, and another in Salisbury, South Australia. These facilities will be instrumental in supporting the women’s health market and dermatology industry growth, ensuring the production of high-quality pharmaceuticals for both U.S. and international markets.

What Are the Financial and Regulatory Details of the Transaction?

The transaction is structured as a scheme arrangement, under which Cosette Pharmaceuticals will acquire 100% of Mayne Pharma’s outstanding shares. Upon completion, the combined company will be privately held, enabling greater flexibility in decision-making and investment in research and development. The acquisition is subject to several customary closing conditions, including regulatory reviews, shareholder approval, and clearance by the Foreign Investment Review Board (FIRB) in Australia.

Both companies have enlisted top-tier financial and legal advisors to oversee the transaction. Cosette Pharmaceuticals is being advised by Santander US Capital Markets LLC and UBS Investment Bank, with legal counsel provided by Ropes & Gray LLP and Corrs Chambers Westgarth. Mayne Pharma has engaged Jefferies Australia as its financial advisor, with Gilbert + Tobin and Arnold & Porter handling legal matters.

How Will This Acquisition Impact the Pharmaceutical Market?

The acquisition of Mayne Pharma by Cosette Pharmaceuticals is expected to have far-reaching implications for the pharmaceutical acquisition news landscape. Analysts view this transaction as a strategic move that aligns with the growing demand for specialized women’s health and dermatology treatments. The global dermatology sector is projected to see sustained growth, driven by rising awareness of skin health, increased demand for personalized treatments, and ongoing advancements in drug development. Similarly, the women’s health market continues to experience expansion, with increasing demand for hormonal therapies, contraceptive options, and menopause-related treatments.

With this acquisition, Cosette Pharmaceuticals will be better positioned to capture emerging opportunities in both sectors. The company’s expanded portfolio and enhanced manufacturing capabilities will allow it to scale its operations and provide innovative treatments to a wider audience. By combining forces with Mayne Pharma, Cosette aims to accelerate research and development efforts, ensuring that new therapies reach patients more efficiently.

What’s Next for Cosette Pharmaceuticals Following the Acquisition?

As the transaction moves toward completion, the focus will shift to the integration of Mayne Pharma’s assets into Cosette Pharmaceuticals’ operations. Industry observers will be monitoring how the combined entity capitalizes on its expanded portfolio and enhanced market presence. The acquisition is expected to drive further investments in innovation, strengthen Cosette’s commercial infrastructure, and expand its reach within the women’s health market and dermatology industry growth sectors.

The coming months will be critical as Cosette Pharmaceuticals works through regulatory approvals and begins the integration process. Once finalized, the acquisition is set to reinforce Cosette’s status as a leader in specialty pharmaceuticals, offering a comprehensive range of treatments tailored to the needs of patients worldwide.