Phase 2 study of the antitumour activity and safety of simlukafusp alfa (FAP-IL2v) combined with atezolizumab in patients with recurrent and/or metastatic cervical squamous cell carcinoma

EBioMedicine. 2024 Nov:109:105374. doi: 10.1016/j.ebiom.2024.105374. Epub 2024 Oct 11.

Abstract

Background: Simlukafusp alfa (FAP-IL2v) is an immune cytokine engineered to selectively promote immune responses in the tumour microenvironment. We evaluated the antitumour activity and safety of FAP-IL2v plus atezolizumab in recurrent and/or metastatic cervical squamous cell carcinoma (SCC) in a phase 2 basket study (NCT03386721).

Methods: Patients with confirmed metastatic, persistent or recurrent cervical SCC who had progressed on ≥1 anti-cancer therapy and had measurable disease were enrolled. FAP-IL2v 10 mg was administered once every 3 weeks (Q3W) or once weekly (QW) for 4 weeks then once every 2 weeks (Q2W) with the corresponding Q3W or Q2W atezolizumab regimens. The primary endpoint was objective response rate by investigator assessment.

Findings: Forty-eight patients were enrolled (Q3W: n = 47; QW/Q2W: n = 1). Among 45 response evaluable patients, objective responses occurred in 12 patients (27%; CI 16.0-41.0), including 3 complete and 9 partial responses. Responses occurred in 6/19 PD-L1 positive patients (32%; 95% CI 15.4-54.0) and 5/24 PD-L1 negative patients (21%; 95% CI 9.2-35.6). Median duration of response was 13.3 months (95% CI 7.6-NE). Median progression-free survival was 3.7 months (95% CI 3.3-9.0). Adverse events (AEs) were consistent with the known safety profile of each drug. AEs leading to withdrawal of either agent occurred in 6 patients (13%). Pronounced expansion and activation of natural killer and CD8 T cells in peripheral blood and increased tumour infiltration and inflammation were observed.

Interpretation: FAP-IL2v plus atezolizumab is clinically active and has manageable safety in patients with recurrent and/or metastatic cervical SCC.

Funding: F. Hoffmann-La Roche Ltd.

Keywords: Cervical cancer; IL-2; Immunotherapy; PD-L1; Squamous cell carcinoma.

Publication types

  • Clinical Trial, Phase II
  • Multicenter Study

MeSH terms

  • Adult
  • Aged
  • Antibodies, Monoclonal, Humanized* / administration & dosage
  • Antibodies, Monoclonal, Humanized* / adverse effects
  • Antibodies, Monoclonal, Humanized* / therapeutic use
  • Antineoplastic Combined Chemotherapy Protocols / adverse effects
  • Antineoplastic Combined Chemotherapy Protocols / therapeutic use
  • Carcinoma, Squamous Cell* / drug therapy
  • Carcinoma, Squamous Cell* / mortality
  • Carcinoma, Squamous Cell* / pathology
  • Female
  • Humans
  • Middle Aged
  • Neoplasm Metastasis
  • Neoplasm Recurrence, Local* / drug therapy
  • Recombinant Fusion Proteins / administration & dosage
  • Recombinant Fusion Proteins / adverse effects
  • Recombinant Fusion Proteins / therapeutic use
  • Treatment Outcome
  • Uterine Cervical Neoplasms* / drug therapy
  • Uterine Cervical Neoplasms* / mortality
  • Uterine Cervical Neoplasms* / pathology

Substances

  • atezolizumab
  • Antibodies, Monoclonal, Humanized
  • Recombinant Fusion Proteins

Associated data

  • ClinicalTrials.gov/NCT03386721