Ballerup, Denmark | April 30, 2026
LEO Pharma has announced a definitive agreement to acquire Replay, significantly expanding its pipeline in rare dermatological diseases through the addition of a next-generation herpes simplex virus (HSV)-based gene therapy platform. This strategic acquisition strengthens LEO Pharma’s position in advanced biologics and reinforces its long-term commitment to innovation in medical dermatology, particularly in addressing high unmet needs in rare genetic skin disorders.
Strategic Acquisition Expands Rare Disease Pipeline
The acquisition integrates Replay’s high-payload HSV gene delivery platform into LEO Pharma’s portfolio, combining decades of dermatology expertise with cutting-edge gene therapy technology. Replay’s platform leverages engineered HSV vectors capable of delivering large therapeutic genes directly into skin cells, offering a unique advantage in treating genetically driven dermatological conditions.
The transaction includes an upfront payment of $50 million, along with milestone payments and tiered royalties, reflecting the high strategic value of gene therapy assets in rare disease markets. This move positions LEO Pharma at the forefront of precision dermatology and next-generation biologics development.
HSV Gene Therapy Enables Targeted Skin Treatment
Advertisement
Replay’s technology is based on viral gene therapy, where modified viruses are used to deliver therapeutic genetic material into cells to correct disease at its source. The HSV-based platform is particularly suited for dermatology due to its natural affinity for skin cells and its ability to deliver large genetic payloads, enabling treatment of complex genetic conditions.
The therapy is formulated as a topical gel applied directly to the skin, allowing localized and targeted gene delivery. This innovative approach represents a major advancement in non-invasive gene therapy, potentially improving treatment precision, patient adherence, and safety outcomes.
Lead Program Targets Devastating Rare Skin Disease
The lead candidate from Replay’s pipeline is currently in preclinical development for dystrophic epidermolysis bullosa (DEB), a rare and debilitating genetic disorder characterized by extreme skin fragility, chronic wounds, and increased risk of skin cancer. DEB remains an area of significant unmet medical need, with limited effective treatment options available, making it a key focus for advanced therapeutic development.
By combining Replay’s gene therapy platform with LEO Pharma’s global dermatology infrastructure, the companies aim to accelerate the development of transformative treatments for patients suffering from this condition. This collaboration underscores the growing importance of gene therapy in addressing rare diseases at a molecular level.
Strengthening Innovation Through Platform Synergy
LEO Pharma plans to leverage Replay’s specialized HSV engineering and manufacturing expertise to drive continued innovation across its dermatology pipeline. The integration of gene therapy capabilities with LEO Pharma’s existing research and development infrastructure creates a powerful synergy, enabling faster progression from preclinical research to clinical development.
Additionally, the use of AI-driven scouting platforms such as Innoviewer™ highlights the increasing role of digital tools in identifying high-potential biopharma opportunities. This acquisition aligns with broader industry trends toward precision medicine, biologics, and targeted therapies for rare diseases.
Advancing the Future of Dermatology and Gene Therapy
The combination of advanced gene therapy platforms and established dermatology expertise is expected to accelerate the development of innovative, disease-modifying treatments for patients with rare genetic skin conditions. By focusing on therapies that address the root genetic causes of disease, LEO Pharma is positioning itself as a leader in next-generation dermatological innovation, with the potential to transform patient outcomes and redefine standards of care. This strategic expansion reflects the growing convergence of biotechnology, genetic medicine, and clinical dermatology, shaping the future of therapeutic development.
Source: LEO Pharma, Replay press release
