Krystal Biotech Provides Update On Oncology Program KB707 And Prioritizes Inhaled KB707 for The Treatment Of Non-Small Cell Lung Cancer

Krystal Biotech, Inc., a commercial-stage biotechnology company, has announced updated development plans for KB707, its redosable immunotherapy designed to provide sustained, localized expression of interleukin-2 (IL-2) and interleukin-12 (IL-12) in the tumor microenvironment while promoting systemic immune-mediated tumor clearance. The therapy is being developed for delivery either through inhalation or intratumoral injection for the treatment of solid tumors. 

Based on encouraging early evidence of efficacy in non-small cell lung cancer (NSCLC), the U.S. Food and Drug Administration (FDA) granted the company an End of Phase 2 meeting in October to discuss potential registration pathways for inhaled KB707. The prioritization of inhaled KB707 is supported by evidence of monotherapy activity and durable responses in heavily pre-treated NSCLC patients, which was presented earlier this year at the 2025 American Society of Clinical Oncology (ASCO) Annual Meeting. 

Suma Krishnan, President of Research and Development of Krystal Biotech, stated, “The acceleration of our work on inhaled KB707 is a reflection of both the clear and acute unmet need that exists for new treatments of NSCLC and the promising efficacy profile we have observed to date with inhaled KB707. We look forward to meeting with the FDA and bringing another urgently needed therapeutic option to patients.”

As of the April 15, 2025 data cut-off, inhaled KB707 demonstrated an objective response rate of 36% in this patient cohort. Median duration of response and progression-free survival were not yet reached. Importantly, inhaled KB707 was found to be safe and generally well tolerated in an outpatient setting, with no Grade 4 or 5 adverse events observed. Enrollment is ongoing in KYANITE-1, a Phase 1/2 open-label, multi-center, dose escalation and expansion study evaluating inhaled KB707 in patients with locally advanced or metastatic solid tumors of the lung. Information about this trial is available at www.clinicaltrials.gov under NCT identifier NCT06228326.

With the company’s decision to focus on inhaled KB707, enrollment has been paused in OPAL-1, a Phase 1/2 open-label, multi-center study evaluating intratumoral KB707 in patients with locally advanced or metastatic solid tumors. Patients already enrolled in OPAL-1 will continue to be monitored, and future development of the intratumoral approach will be reassessed based on the safety and efficacy outcomes observed. Details of OPAL-1 can be found at www.clinicaltrials.gov under NCT identifier NCT05970497.

Through this strategy, Krystal Biotech aims to advance inhaled KB707 as a potentially transformative therapy for patients with NSCLC and other solid tumors, while continuing to evaluate opportunities for its intratumoral application.