Krystal Biotech, Inc. announced that the first patient was dosed in its Phase 1 clinical trial (KYANITE-1) evaluating inhaled KB707, a modified HSV-1 vector designed to deliver genes encoding both human interleukin-12 (IL-12) and interleukin-2 (IL-2) to the lung, for the treatment of patients with locally advanced or metastatic solid tumors of the lung. The KYANITE-1 clinical trial is an open-label, multicenter, dose escalation and expansion study to evaluate inhaled KB707 monotherapy in patients with advanced solid tumor malignancies affecting the lungs. Details of the KYANITE-1 study can be found at www.clinicaltrials.gov under NCT identifier: NCT06228326.

In February 2024, the U.S. Food and Drug Administration (FDA) granted Fast Track Designation for inhaled KB707 for the treatment of patients with solid tumors with pulmonary metastases that are relapsed or refractory to standard of care therapy. This is the second Fast Track Designation for the KB707 program. In July 2023, the FDA granted intratumoral KB707 Fast Track Designation for the treatment of anti-PD-1 relapsed/refractory locally advanced or metastatic melanoma.

IL-2 and IL-12 are secreted cytokines with complementary functions promoting cell-mediated immunity in humans. Both IL-2 and IL-12 have been shown to elicit anti-tumor immune responses in preclinical models and in clinical settings and have been extensively studied for their potential in cancer immunotherapy. Despite promising signs of efficacy, it has proven difficult to effectively harness IL-2 and IL-12 for therapeutic benefit, as systemic administration is often poorly tolerated, and their inherently short half-lives necessitate high dose levels and extremely frequent dose intervals.

KB707 is a modified HSV-1 vector designed to deliver genes encoding both human IL-12 and IL-2 directly to a patient?s tumor(s) and promote systemic immune-mediated tumor clearance. KB707 targets solid tumors that are accessible via intratumoral injection or inhalation.