Dual-Target Immunotherapy Shows 52% Response
BioNTech's dual-target immunotherapy achieved a 52% response rate in people with mesothelioma. Results presented at ASCO 2025.
A New Contender in Mesothelioma Treatment
The immunotherapy landscape for mesothelioma may be shifting again. At the 2025 ASCO Annual Meeting, BioNTech presented Phase 2 data showing that its experimental drug BNT327, combined with chemotherapy, produced tumor shrinkage in more than half of previously untreated patients, a response rate that rivals or potentially exceeds currently approved immunotherapies.
The results are preliminary, drawn from just 31 patients in a single-arm Chinese trial. But the numbers have caught the attention of researchers who have seen few new options emerge for this difficult-to-treat cancer.
How BNT327 Works
Most mesothelioma immunotherapies target a single pathway. BNT327 takes a different approach.
The drug is a bispecific antibody, a molecule engineered to bind two different targets simultaneously. One arm blocks PD-L1, an immune checkpoint that tumors exploit to hide from the immune system. The other arm blocks VEGF-A, a protein that tumors use to grow new blood vessels and secure their nutrient supply.
By hitting both targets with one drug, the theory goes, BNT327 attacks mesothelioma on two fronts: unleashing the immune system while cutting off the tumor’s lifeline.
The Numbers
Of 31 patients who received BNT327 plus standard chemotherapy, 16 saw their tumors shrink significantly, an overall response rate of 51.6%. One patient achieved a complete response, meaning no detectable cancer remained on imaging. Another 12 patients had stable disease, meaning their cancer stopped growing.
Add those together, and 90.3% of patients achieved disease control, a striking figure in a cancer where progression often comes quickly.
| Outcome | Patients | Rate |
|---|---|---|
| Complete response | 1 | 3.2% |
| Partial response | 15 | 48.4% |
| Stable disease | 12 | 38.7% |
| Disease control total | 28 | 90.3% |
Perhaps most intriguing were the results in peritoneal mesothelioma, a subtype with no specifically approved treatments. At a median follow-up of 20.3 months, peritoneal patients showed a 75% confirmed response rate and 100% disease control rate.
A 2026 preclinical study in Scientific Reports found that the peritoneal cavity creates an immune-suppressive microenvironment resistant to checkpoint therapy alone. This may explain why BNT327’s dual mechanism, targeting both PD-L1 and VEGF-A, appears particularly effective in this population.
How It Compares
Cross-trial comparisons are imperfect; different patient populations and study designs make direct head-to-head conclusions unreliable. With that caveat, the BNT327 data looks competitive with approved options.
The FDA-approved combination of Opdivo plus Yervoy produces response rates around 40% and disease control around 77% in first-line pleural mesothelioma, with a median progression-free survival of 6.8 months. BNT327’s 52% response rate, 90% disease control, and 16.6-month median PFS appear to improve on both metrics, though a randomized comparison would be needed to know for certain.
Safety Concerns
The treatment wasn’t easy on patients. Nearly all, 93.5%, experienced serious side effects of Grade 3 or higher, primarily blood-related toxicities from the chemotherapy component. Decreased neutrophils and white blood cells were common, as were anemia and low platelet counts.
Five patients, about 16%, discontinued treatment due to side effects. But there were no treatment-related deaths, and the rate of immune-related adverse events was relatively low compared to some immunotherapy combinations.
The safety profile largely reflects the chemotherapy backbone rather than the novel drug itself. Whether BNT327’s dual targeting mechanism introduces unique long-term concerns remains unclear.
The Long Road Ahead
Promising Phase 2 data doesn’t guarantee a new treatment option. BioNTech has acknowledged that mesothelioma, while on its development plan, isn’t the company’s top priority. The drug is advancing more rapidly in lung cancer and triple-negative breast cancer, where larger patient populations make trials faster to complete.
A Phase 3 trial in mesothelioma, the kind of large, randomized study needed for FDA approval, has no announced timeline. Patients hoping to access BNT327 would need to find and enroll in clinical trials, which may be limited geographically.
What Patients Should Know
BNT327 isn’t available outside of clinical trials, and those trials are currently running in China rather than the United States. For patients seeking treatment now, existing options remain the best path forward.
The FDA-approved combination of Opdivo plus Yervoy represents the current standard of care in first-line treatment for appropriate candidates. Chemotherapy continues to play a role, particularly in combination regimens. For patients whose disease has progressed on initial treatment, emerging options like VT3989 are under investigation.
The BNT327 results offer reason for cautious optimism. A drug that can achieve disease control in 90% of patients would represent meaningful progress. But people with mesothelioma have seen promising early data before, and learned to wait for the larger studies that separate hope from reality.
BNT327 is not available outside of clinical trials. Current trials are running in China. For patients seeking treatment now, approved options like Opdivo plus Yervoy remain the standard of care. Ask your oncologist about available clinical trials.
Reader Q&A
Frequently Asked Questions
How does BNT327 differ from current immunotherapies?
Most mesothelioma immunotherapies target a single pathway. BNT327 is a bispecific antibody that simultaneously blocks PD-L1 (an immune checkpoint tumors use to hide from the immune system) and VEGF-A (a protein tumors use to grow blood vessels). This dual-targeting approach attacks mesothelioma on two fronts.
Is BNT327 available to patients now?
No. BNT327 is only available through clinical trials, which are currently running in China, not the United States. BioNTech has acknowledged that mesothelioma isn’t the company’s top priority. The drug is advancing more rapidly in lung cancer and breast cancer trials.
What are the results for peritoneal mesothelioma?
The results in peritoneal mesothelioma were particularly striking. Among eight peritoneal patients in the trial, six responded to treatment (75% confirmed response rate) and all eight achieved disease control. Notably, peritoneal mesothelioma has no specifically approved treatments.
When might BNT327 be FDA approved?
A Phase 3 trial in mesothelioma. The kind of large, randomized study needed for FDA approval. Has no announced timeline. The drug is being prioritized for lung cancer and breast cancer, where larger patient populations make trials faster to complete.
Does mesothelioma cause pneumonia?
Mesothelioma does not directly cause pneumonia. Pneumonia is an infectious lung inflammation, while mesothelioma symptoms such as pleural effusion, shortness of breath, chest pain, and cough can mimic pneumonia on chest X-rays, especially without known asbestos exposure. People with mesothelioma face higher pneumonia risk due to weakened immunity, fluid buildup, or treatment side effects like radiation-induced pneumonitis (non-infectious lung inflammation). Differentiation requires specialized imaging and history review.
What is ASCO in cancer?
The American Society of Clinical Oncology (ASCO) is a professional organization founded in 1964 that represents nearly 50,000 oncology professionals who care for people with cancer. ASCO develops clinical practice guidelines on cancer treatment, prevention, and palliative care across multiple cancer types, and its members contribute to and vet cancer information for public resources. The organization conducts research, provides education, and promotes high-quality, equitable patient care through its work and its foundation, Conquer Cancer, which funds groundbreaking research and education. ASCO collaborates with institutions like the National Cancer Institute (NCI) and the American Cancer Society to advance cancer care delivery and share authoritative information with people affected by cancer.
What famous person died from mesothelioma?
Steve McQueen, a prominent actor known for films like The Great Escape and The Magnificent Seven, died from pleural mesothelioma in 1980 at age 50. His exposure is linked to U.S. Marine service, shipyard work, and possible movie set insulation. Other celebrities who died from mesothelioma include musician Warren Zevon (2003), actor Ed Lauter (2013), and NFL player Merlin Olsen. Paleontologist Stephen Jay Gould survived peritoneal mesothelioma for 20 years before dying from unrelated lung cancer in 2002.
How did Steve McQueen get mesothelioma?
Steve McQueen was exposed to asbestos through multiple occupational and military sources over several decades. His primary exposure occurred during his service in the U.S. Marine Corps from 1947 to 1950, when he worked aboard naval ships and in shipyards, including removing asbestos lagging from pipes at Camp Lejeune. After his military service, he encountered additional asbestos exposure on movie soundstages where insulation contained the mineral, while wearing flame-resistant racing suits made with asbestos, and while working on race car and motorcycle brakes. McQueen did not develop symptoms until 1978, nearly 30 years after his initial military exposure, reflecting the typical latency period of 20 to 50 years between asbestos exposure and mesothelioma diagnosis. He was diagnosed with pleural mesothelioma in December 1979 and died in November 1980 at age 50.