FDA Grants Designation to Immunotherapy KB707 for Advanced NSCLC

The U.S. Food and Drug Administration (FDA) has granted Regenerative Medicine Advanced Therapy (RMAT) designation to KB707, an investigational inhaled immunotherapy being developed by Krystal Biotech for the treatment of advanced or metastatic non-small cell lung cancer (NSCLC). The designation reflects encouraging early clinical data and the continued need for new treatment options for patients whose disease has progressed despite standard therapies.

NSCLC is the most common form of lung cancer and remains one of the leading causes of cancer-related death worldwide. Although targeted therapies and immunotherapies have improved outcomes for some patients, many individuals with advanced disease eventually run out of effective options. The RMAT designation is intended to help speed development of therapies that show potential to address serious, life-threatening conditions, offering cautious optimism for patients and caregivers following ongoing research in this space.

“The FDA’s decision to grant RMAT designation to KB707 reflects both the urgent unmet need for new NSCLC therapies as well as the promising early clinical evidence of efficacy we have observed with inhaled KB707 in patients with advanced NSCLC,” Suma Krishnan, president of Research and Development at Krystal Biotech, said in a news release. “This is the second RMAT designation granted to a Krystal program and, as such, we know first-hand the benefits that this designation can provide to accelerate development and shorten the path to a potential approval. We are excited to work closely with the FDA to maximize the potential impact of our KB707 program for patients with NSCLC.”

What RMAT Designation Means for Patients With NSCLC

RMAT designation is a special regulatory pathway created to support development of regenerative medicine therapies, including gene therapies. To qualify, a treatment must be intended to treat, modify, reverse or cure a serious disease and show preliminary clinical evidence suggesting it could address an unmet medical need.

For KB707, the designation provides multiple benefits that may help move the therapy forward more efficiently. These include closer and more frequent interactions with the FDA, eligibility for rolling review of regulatory submissions, and the opportunity to discuss innovative clinical trial designs or surrogate endpoints that could support accelerated approval in the future. RMAT designation also incorporates advantages of the FDA’s Fast Track and Breakthrough Therapy programs.

Why New Approaches Are Needed in Advanced NSCLC

NSCLC accounts for approximately 85% of all lung cancer diagnoses. Although many patients initially respond to chemotherapy, targeted therapy or immune checkpoint inhibitors, advanced or metastatic disease often becomes resistant to available treatments. Patients whose cancer has progressed after multiple prior therapies face limited options and poor outcomes.

Immunotherapy has transformed lung cancer care, but not all tumors respond, and systemic immune activation can lead to side effects that affect healthy tissues. Researchers continue to explore ways to enhance immune responses within tumors while minimizing effects on the rest of the body. This has driven interest in localized approaches that deliver immune-stimulating agents directly to the tumor environment.

KB707 is a redosable genetic immunotherapy designed to deliver localized expression of two immune-stimulating proteins, interleukin-2 (IL-2) and interleukin-12 (IL-12), directly into the tumor microenvironment. These cytokines are known to activate immune cells capable of attacking cancer, but when given systemically, they can cause significant toxicity.

By administering KB707 via inhalation, the therapy is intended to concentrate immune activation within lung tumors while reducing exposure to the rest of the body. The goal is to drive a sustained antitumor immune response in the lungs without the side effects typically associated with intravenous cytokine therapies.

Patient Population: Who Has Been Studied So Far

The RMAT designation was supported by early clinical evidence from the ongoing KYANITE-1 study, which is evaluating inhaled KB707 in patients with heavily pretreated advanced NSCLC. These patients had previously received multiple lines of therapy and represented a population with limited remaining treatment options.

In this setting, KB707 demonstrated consistent antitumor activity, including durable responses and meaningful tumor shrinkage in some patients. Although the study is ongoing and enrollment continues, the preliminary findings suggest KB707 may offer benefit even in patients with difficult-to-treat disease.

What Comes Next

Krystal Biotech plans to present additional data from the KYANITE-1 study at upcoming scientific meetings. Continued enrollment will help researchers better understand which patients are most likely to benefit and how durable responses may be over time.

For patients and caregivers, the RMAT designation does not mean KB707 is approved or available outside of clinical trials. However, it signals strong regulatory support and recognition of early evidence that the therapy could meaningfully improve outcomes in advanced NSCLC.

References

1. “Krystal Biotech Announces RMAT Designation Granted by FDA to KB707 for the Treatment of Advanced or Metastatic Non-Small Cell Lung Cancer,” by Krystal Biotech, Inc. News release; Feb. 9, 2026.

Editor's note: This article is for informational purposes only and is not a substitute for professional medical advice, as your own experience will be unique. Use this article to guide discussions with your oncologist. Content was generated with AI and reviewed by a human editor.

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