BioNTech adds clinical weight to its oncology pivot at WCLC 2026

BioNTech’s oncology pipeline is increasingly looking different from the one that made the Mainz-based company a household name during the Covid-19 pandemic. While mRNA remains a central technology, the company has been steadily building an oncology portfolio around antibodies, bispecifics and combination approaches.

The latest evidence is coming from the World Conference on Lung Cancer (WCLC) in Seoul, where BioNTech is presenting clinical data from several stages of development. The most mature signal comes from gotistobart, an anti-CTLA-4 antibody being developed with US partner OncoC4. Meanwhile, longer-term data for the bispecific antibody pumitamig and early results from a pumitamig–ADC combination add further evidence that BioNTech is trying to build a broad, combination-driven oncology franchise.

Gotistobart: a potential chemotherapy-free option

The most advanced clinical readout comes from gotistobart (BNT316/ONC-392), a pH-sensitive anti-CTLA-4 antibody originally developed by OncoImmune and now being advanced by OncoC4 in partnership with BioNTech.

In the Phase III PRESERVE-003 study, patients with previously treated squamous non-small cell lung cancer (NSCLC) achieved a median overall survival of 18.5 months with gotistobart versus 10.0 months with docetaxel. The result corresponds to an approximately 54% reduction in the risk of death.

The patient population is clinically relevant but difficult to treat: their disease had progressed following an anti-PD-(L)1 therapy and platinum-based chemotherapy, leaving relatively few established treatment options.

What makes gotistobart different from a conventional CTLA-4 inhibitor is its proposed mechanism. Rather than simply blocking CTLA-4 systemically, the antibody is designed to preferentially target CTLA-4-positive regulatory T cells (Tregs) within the tumor microenvironment. Its pH-sensitive design is intended to promote CTLA-4 recycling and selectively modulate the immune response in the tumor while limiting systemic immune activation.

That distinction could become important if the approach can deliver the efficacy associated with CTLA-4 targeting without the toxicity that has limited broader use of the mechanism.

The current data, however, should not yet be mistaken for definitive registrational evidence. The initial portion of PRESERVE-003 was designed to establish the clinical signal; the ongoing pivotal portion is intended to confirm the benefit. Gotistobart is being tested as a chemotherapy-free monotherapy against docetaxel, with overall survival as the primary endpoint.

For BioNTech, this is strategically important. A positive pivotal readout would give the company a late-stage oncology asset that is independent of its mRNA cancer vaccine programs and could potentially address a substantial unmet need in second-line and later-line lung cancer.

Pumitamig: from acquisition to potential oncology backbone

Further down the development timeline, but potentially broader in commercial scope, is pumitamig (BNT327/BMS-986545), a bispecific antibody targeting PD-L1 and VEGF-A.

The program originated at Chinese biotech Biotheus. BioNTech first entered into a global licensing and collaboration agreement with Biotheus and subsequently acquired the company, obtaining full global rights to pumitamig. In June 2025, BioNTech entered into a global development and commercialization partnership with Bristol Myers Squibb. BMS paid $1.5 billion upfront, with additional payments and potential milestones worth several billion dollars.

That deal was more than a financing event. It effectively validated BioNTech’s ambition to turn pumitamig into one of the central pillars of its post-Covid oncology strategy.

At WCLC, BioNTech is presenting longer-term Phase II data in previously untreated patients with unresectable mesothelioma. After a median follow-up of 23.5 months, median progression-free survival was 16.6 months, while median overall survival reached 25.8 months. The two-year overall survival rate was 50.7%.

The results were 15.8 months for median PFS and 23.5 months for median OS in pleural mesothelioma, while patients with peritoneal mesothelioma showed median PFS and OS of 25.1 and 27.1 months, respectively.

The numbers are encouraging, but their interpretation needs to remain cautious. The study enrolled only 31 patients, was single-arm and had no control group. The data therefore do not establish pumitamig as a superior treatment in mesothelioma. Their main value at this stage is as a signal that the drug’s activity can be sustained over time and potentially extended beyond the tumor types in which it was initially developed.

For BioNTech, that breadth matters. The company is pursuing pumitamig as a potential pan-tumor combination backbone, rather than as a single-indication product.

The more interesting experiment: bispecific plus ADC

The most strategically interesting development may therefore not be the mesothelioma data at all, but the early evidence from combining pumitamig with an antibody-drug conjugate.

The combination pairs pumitamig with elfetabart drozuntecan (also known as DB-1311/BNT324), a B7-H3-targeted ADC being developed with Chinese partner DualityBio. The ADC uses a topoisomerase I inhibitor payload and is designed to target B7-H3, a surface protein broadly expressed across a range of solid tumors, including lung and ovarian cancers.

At a WCLC press briefing, BioNTech reported encouraging response rates across treatment lines in NSCLC: 92% in first-line treatment, 76% in second line and 54% in third line.

The combination also showed activity in small-cell lung cancer (SCLC), including a population with a relatively high burden of brain and liver metastases, where the reported response rate remained above 70%.

The durability of these responses could ultimately be more important than the early response rates themselves. More than 80% of the patients included in the analysis were still receiving treatment at the time of the preliminary data cut, according to BioNTech. Further follow-up is therefore likely to be closely watched.

The underlying strategy is straightforward: rather than relying on a single mechanism, BioNTech is trying to combine immune activation through pumitamig with direct tumor-cell killing through an ADC. If the approach holds up in larger and more mature datasets, it could provide a modular way of applying the same immunological backbone across several solid tumors.

From mRNA pioneer to multi-platform oncology company

Taken together, the WCLC data illustrate a broader transformation at BioNTech.

The company is still closely associated with mRNA vaccines, but its oncology strategy increasingly depends on antibodies and combinations. Pumitamig is central to that shift because of its potential to be combined with different therapeutic modalities. Gotistobart adds a late-stage, mechanistically differentiated checkpoint program, while the B7-H3 ADC combination illustrates how BioNTech is attempting to build multi-mechanistic treatment regimens rather than individual drug candidates.

The scale of the effort is already considerable. BioNTech says its lung cancer development program comprises more than 16 clinical trials, including five Phase III studies.

What comes next?

The decisive test will now be clinical validation rather than additional promising signals.

For gotistobart, the priority is the pivotal portion of PRESERVE-003 and whether the survival advantage seen so far can be confirmed against docetaxel. For pumitamig, the focus is shifting toward larger, controlled studies across lung cancer and other solid tumors, as well as the emerging combination programs.

The commercial partnership with BMS also raises the stakes. Pumitamig is no longer simply a promising BioNTech asset; it is a potential cornerstone of a global oncology franchise backed by one of the world’s largest pharmaceutical companies.

That makes the Seoul data relevant beyond the individual trial results. They suggest that BioNTech’s oncology pipeline is beginning to acquire the breadth and clinical maturity needed to compensate for the limitations of a strategy centered on cancer vaccines alone. The next step is to show that this breadth can be converted into approved products.