LEO Pharma Finalizes Acquisition of Spesolimab for GPP

LEO Pharma recently announced it has officially closed its acquisition of spesolimab (Spevigo) from Boehringer Ingelheim, following regulatory approvals across all relevant authorities. The deal, first disclosed on July 14, 2025, positions spesolimab as the third strategic brand within LEO Pharma’s global dermatology portfolio.^1,2

Spesolimab is a humanized, selective monoclonal antibody that targets and blocks activation of the IL-36 receptor, a central pathway in the pathogenesis of autoinflammatory skin diseases, including generalized pustular psoriasis (GPP).

The US FDA approved spesolimab for GPP in 2022 for adults as the first treatment specifically indicated for GPP flares. The approval was based on positive data from the pivotal Effisayil 1 trial (NCT03782792), a randomized, double-blind, placebo-controlled study demonstrating rapid pustular and systemic symptom clearance following a single intravenous dose.³ Spesolimab received an expanded FDA indication in March 2024 for pediatric patients aged 12 years and older weighing ≥40 kg based on data from Effisayi 2 (NCT04399837).⁴

“With our specialization in dermatology, LEO Pharma is uniquely positioned to take over Spevigo and expand access to care, bringing progress to underserved patients,” said Christophe Bourdon, CEO of LEO Pharma, in the news release. “We are committed to ensuring this innovative treatment reaches its full potential by building on Boehringer Ingelheim’s pioneering efforts. Bringing Spevigo to more patients is an important step in helping those living with GPP, a community with limited treatment options.”¹

Spesolimab is approved in over 40 countries, including the US, Japan, China, and the European Union, for acute GPP flares. It has also received expanded indications in some jurisdictions for broader use in GPP management and is currently under investigation for other IL-36-mediated dermatoses.⁵

LEO Pharma will assume responsibility for commercialization and further clinical development of spesolimab, leveraging its established dermatology platform to accelerate access to therapy worldwide. Beyond GPP, spesolimab is being investigated for pyoderma gangrenosum, signaling potential future indications of interest to dermatology clinicians managing complex inflammatory skin disorders.¹

Financially, spesolimab will be reflected in LEO Pharma’s FY 2025 results with 3 months of contribution. The company anticipates spesolimab will add less than 1% to revenue growth for the year, while development-related expenses may reduce adjusted EBITDA margin by up to two percentage points. LEO Pharma has reaffirmed its broader financial outlook of 7% to 9% revenue growth at constant exchange rates and a 16% to 18% adjusted EBITDA margin, excluding spesolimab.¹

Clinical Context

GPP is a rare, heterogeneous, and potentially life-threatening dermatologic condition characterized by the rapid accumulation of neutrophils in the skin, resulting in widespread, painful, sterile pustules. Patients may experience relapsing episodes marked by fever, malaise, fatigue, and risk of organ failure, while others live with persistent disease punctuated by intermittent flares. Current treatment options remain limited, and spesolimab represents the first targeted biologic developed specifically to address the IL-36 pathway.¹

References

1. LEO Pharma closes deal for Spevigo. News release. LEO Pharma. October 1, 2025. Accessed October 3, 2025. https://www.leo-pharma.com/media-center/news/2025-spevigo-closing

2. Boehringer Ingelheim and LEO Pharma enter partnership to commercialize and further develop Spevigo (spesolimab). News release. Boehringer Ingelheim. July 14, 2025. Accessed October 3, 2025. https://www.boehringer-ingelheim.com/human-health/skin-and-inflammatory-diseases/gpp/boehringer-leo-pharma-partnership-commercialize-spevigo

3. FDA approves the first treatment option for generalized pustular psoriasis flares in adults. News release. Boehringer Ingelheim. September 1, 2022. Accessed October 3, 2025. https://www.boehringer-ingelheim.com/us/press-release/fda-approves-first-treatment-option-generalized-pustular-psoriasis-flares-adults

4. Morita A, Strober B, Burden AD, et al. Efficacy and safety of subcutaneous spesolimab for the prevention of generalised pustular psoriasis flares (Effisayil 2): an international, multicentre, randomised, placebo-controlled trial. Lancet. 2023;402(10412):1541-1551. doi: 10.1016/S0140-6736(23)01378-8

5. Spevigo approved for expanded indications in China and the US. News release. Boehringer Ingelheim. March 19, 2024. Accessed October 3, 2025. https://www.boehringer-ingelheim.com/us/human-health/skin-and-inflammatory-diseases/gpp/spevigo-approved-expanded-indications-china-and-us