Generate:Biomedicines announced plans to launch two global Phase 3 clinical trials, SOLAIRIA-1 and SOLAIRIA-2, to evaluate GB-0895, a long-acting anti-TSLP monoclonal antibody designed using the company’s AI-enabled “generative biology” platform. GB-0895 is among the leaders in a pack of long-acting TSLP-targeted biologics under clinical development, while also representing the first AI-engineered biologic drug candidate to progress to late-stage clinical development.
Tackling severe asthma with AI-designed biology
GB-0895 was engineered using Generate’s machine-learning and high-throughput protein optimization platform, which aims to design antibodies with precise binding, extended half-life, and improved manufacturability. The antibody targets thymic stromal lymphopoietin (TSLP), an epithelial “alarmin” cytokine positioned at the top of the type 2 inflammatory cascade. TSLP plays a key role in amplifying allergic responses implicated in asthma, atopic dermatitis, and other inflammatory diseases.
By blocking TSLP upstream, GB-0895 may reduce exacerbations in patients whose severe asthma remains inadequately controlled on current standard-of-care options.
Study scale and design
Together, SOLAIRIA-1 and SOLAIRIA-2 will enroll approximately 1,600 adults and adolescents with severe, uncontrolled asthma across more than 40 countries spanning North America, Europe, Latin America, and Asia-Pacific.
Participants will receive 300 mg of GB-0895 subcutaneously every six months or placebo. The primary endpoint is the reduction in annualized clinically significant asthma exacerbations over 52 weeks. Secondary endpoints include lung function (FEV₁), symptom control, and patient-reported quality-of-life assessments.
Promising early data supports rapid advancement
Phase 1 data, presented at the European Respiratory Society International Congress 2025, showed that GB-0895 was generally well tolerated across doses ranging from 10 mg to 1,200 mg. The antibody demonstrated dose-proportional pharmacokinetics with an extended ~89-day half-life and sustained suppression of TSLP-related biomarkers, consistent with durable blockade lasting at least six months. These results support the twice-yearly dosing strategy employed in the Phase 3 program.
Generate also noted that GB-0895 is being evaluated in an ongoing Phase 1 trial for chronic obstructive pulmonary disease (COPD), underscoring its broader respiratory potential.
The emerging TSLP inhibitor landscape
The first and, so far, only approved TSLP inhibitor for asthma is Tezspire (tezepelumab), developed by Amgen and AstraZeneca and marketed globally since 2021. Tezspire is administered once monthly (210 mg SC) and has demonstrated broad efficacy across biomarker-defined asthma phenotypes. GB-0895 could offer a major dosing advantage with its twice-yearly schedule, pending comparable efficacy.
The pipeline has also accelerated:
- Sanofi’s lunsekimig (SAR443765), an IL-13/TSLP bispecific nanobody, entered Phase 3 testing in asthma and is expected to use a once- or twice-monthly dosing regimen based on earlier trials.
- GSK’s GSK5784283 (AIO-001/SHR1905), acquired through GSK’s 2024 purchase of Aiolos Bio, is a long-acting anti-TSLP antibody from Jiangsu Hengrui with a twice-yearly dosing schedule similar to GB-0895. It is currently the subject of a Phase 2 trial.
- Roche-Qyuns’ QX031N: In late 2025, Roche signed a deal exceeding USD 1 billion to acquire global rights to QX031N, a preclinical IL-33/TSLP bispecific antibody, further boosting industry activity around epithelial alarmin pathways.
A milestone for AI-driven drug development
According to Generate’s CEO, advancing GB-0895 into Phase 3 “marks an important milestone for Generate and for the field”, a success story that illustrates the potential for programmable biology approaches to accelerate the development of biologics.
Despite widespread investment in AI-discovered therapeutics, the first wave of programs has seen significant attrition in Phase 1 and 2. Only a small number—such as Relay Therapeutics’ RLY-2608 (a next-generation PI3Kα inhibitor for breast cancer) and Insilico Medicine’s rentosertib (ISM001-055) for idiopathic pulmonary fibrosis—have achieved clinical proof-of-concept and progressed toward Phase 3 evaluation.
Notably, early AI drug development platforms have in the main focused on small molecule drugs. Generate’s advancement of an AI-engineered antibody into global Phase 3 trials means the Somerville, Massachusetts-based biotech is a pioneer in translating AI-enabled molecular design into late-stage human studies.