Leo Pharma agreed to acquire Replay Holdings for $50 million, marking its entry into gene therapy through Replay’s high-capacity herpes simplex virus (HSV) vectors. The seed-stage portfolio is centered on delivering genetic payloads for rare inherited diseases, with Leo targeting dermatology as its initial therapeutic entry point. Replay is developing platform and asset spinouts, including a focus on a topical HSV gene therapy approach for dystrophic epidermolysis bullosa. The acquisition adds medical-dermatology execution capabilities to a vector platform designed to support redosing and high payload delivery. The deal illustrates how established dermatology brands are moving beyond biologics and small molecules toward gene-delivery modalities to widen platform depth and differentiate rare disease offerings.