In July 2025, the U.S. Food and Drug Administration (FDA) granted VT3989 orphan drug designation for the treatment of recurrent mesothelioma. VT3989 is an oral medication made by Vivace Therapeutics and works by blocking specific proteins that help cancer cells stay alive and spread.
Mesothelioma recurrence means the cancer has come back after treatment. It may reappear in the same area where it first started or spread to new parts of the body. When mesothelioma returns, it’s often harder to treat because options are limited and the cancer can be more aggressive.
“The granting of orphan drug designation to VT3989 underscores the critical need for new, effective therapies for mesothelioma, an aggressive cancer with limited treatment options,” explained Dr. Sofie Qiao, the president and chief executive officer of Vivace Therapeutics.
How Does VT3989 Work for Mesothelioma?
VT3989 is a type of targeted mesothelioma therapy that’s designed to go after weak spots in cancer cells without harming as many healthy cells.
It targets two key proteins that help mesothelioma grow:
- Focal adhesion kinase (FAK)
- Proline-rich tyrosine kinase 2 (PYK2)
By blocking FAK and PYK2, VT3989 disrupts mesothelioma’s ability to sustain itself, potentially slowing disease spread and making cancer cells more vulnerable to treatment.
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Patient Results from the VT3989 Clinical Trial
Researchers tested VT3989 in a phase I clinical trial led by MD Anderson Cancer Center. The study focused on patients with recurring mesothelioma who had already received chemotherapy and immunotherapy.
The results showed several encouraging trends:
- Partial tumor shrinkage – Of the patients in the trial, 7 had their tumors shrink enough to count as a “partial response.” Six of these were confirmed on follow-up scans.
- Stable disease – There were 34 participants who had “stable disease,” meaning their cancer stopped growing for a period of time.
- Benefits for both mesothelioma types – VT3989 showed success in patients with pleural mesothelioma (which affects the lung lining) and peritoneal mesothelioma (which affects the abdominal lining).
- Good safety profile – There were no treatment-related deaths, and most side effects were mild to moderate.
Some patient responses lasted well over 1.5 years, and the drug was successful in treating both pleural and peritoneal mesothelioma.
“We are committed to continuing clinical development of VT3989 and discussing a move into a registrational phase 3 study in mesothelioma with the FDA by the end of 2025,” Dr. Qiao stated.
What the New FDA Status Means for Patients & Families
The FDA has given VT3989 orphan drug designation — a special status for medicines that could help people with rare diseases like mesothelioma.
Here’s what that means:
- Faster potential access to the drug – This designation lets the drug’s developer work more closely with the FDA, which can speed up clinical trials and the review process. That means patients might get access to new treatment options sooner.
- New hope for hard-to-treat cases – If it’s eventually approved, VT3989 could offer an option for people who haven’t responded well to standard treatments. It aims not only to shrink tumors but also to help patients keep a good quality of life for longer.
- Stronger support for research – Orphan drug status makes it easier for Vivace Therapeutics to keep testing VT3989 in human trials, which is vital for proving its safety and effectiveness.
The FDA’s orphan drug designation for VT3989 is a strong sign that experts believe this drug could help people with mesothelioma. While it doesn’t mean VT3989 is approved yet, it shows that the FDA sees enough promise to support its continued development.
Get Help Finding Treatment for Mesothelioma
If you or a loved one is facing mesothelioma, you don’t have to navigate treatment alone. Mesothelioma Hope’s nurses and Patient Advocates are dedicated to providing free resources and support at every step of your cancer journey.
Our team can help you:
- Understand your diagnosis and treatment options
- Find top mesothelioma specialists
- Manage symptoms and side effects
- Pursue compensation for your medical care
Every day matters when it comes to mesothelioma treatment. Contact Mesothelioma Hope now or call (866) 608-8933 to speak with us and get the help you need.
