# Genmab's Bispecific Antibody Cuts Death Risk by 50% in Cancer Trial

> Genmab's latest trial results show that its bispecific antibody, petosemtamab, significantly enhances treatment outcomes for head and neck cancer, halving the risk of death when used with Keytruda. This breakthrough positions Genmab as a leading innovator in oncology.

**Source**: fiercebiotech.com | **Published**: 2026-10-29 | **Type**: article

## Key Facts

- Genmab's bispecific antibody cut death risk by 50%, enhancing its competitive edge in oncology.
- $4B peak sales forecast for petosemtamab indicates strong financial potential in HNSCC market.
- Acquisition of Merus for $8B now justified by successful trial outcomes, reducing investment risk.
- Combination therapy shows 3.17x higher response rate, highlighting innovative treatment advantages.
- Strategic focus on multiple cancer types suggests adaptability and long-term growth for Genmab.

## Summary

Genmab has made significant strides in oncology with the announcement of promising phase 3 trial results for its bispecific antibody, petosemtamab. The interim analysis revealed that combining petosemtamab with Merck & Co.'s Keytruda reduced the risk of death by 50% in patients suffering from PD-L1-positive recurrent or metastatic head and neck squamous cell carcinoma (HNSCC). This development is crucial as it not only highlights the potential of bispecific therapies but also positions Genmab as a formidable player in the competitive oncology market.

The results were disclosed shortly after the European Society for Medical Oncology (ESMO) congress in Madrid, where Genmab showcased its advancements. The late-stage LiGeR-HN1 study met both primary endpoints, demonstrating statistically significant improvements in overall survival and objective response rates when compared to Keytruda alone. Specifically, the combination therapy achieved a hazard ratio of 0.50 for overall survival and an odds ratio of 3.17 for objective response, indicating a substantial enhancement in treatment efficacy.

Genmab's acquisition of Merus for $8 billion last year has proven strategic, as it brought petosemtamab into its portfolio. This bispecific antibody targets both the epidermal growth factor receptor (EGFR) and the novel oncology target leucine-rich repeat-containing G-protein-coupled receptor 5 (LGR5). The acquisition not only expands Genmab's therapeutic offerings but also reinforces its commitment to innovation in cancer treatment.

The safety profile of the combination therapy remains consistent with prior findings, with no new safety signals reported. This stability is essential for gaining regulatory approval and building clinician confidence in the treatment. Genmab's CEO, Jan van de Winkel, emphasized the significance of these results, framing petosemtamab as a potential first-in-class option for patients with challenging cancer types.

Market analysts are optimistic about the commercial potential of petosemtamab. A report from William Blair anticipates peak sales of $4 billion for the drug in HNSCC alone. Genmab is also exploring the efficacy of petosemtamab in additional settings, including second- and third-line treatments for recurrent or metastatic HNSCC and colorectal cancer, through three ongoing phase 3 studies.

In addition to the success of petosemtamab, Genmab reported a phase 3 win for its antibody-drug conjugate rinatabart sesutecan in platinum-resistant ovarian cancer during the ESMO congress. This dual success underscores Genmab’s robust pipeline and its ability to capitalize on innovative therapies in oncology.

Looking ahead, the positive trial outcomes signal a shift in the competitive landscape of cancer therapies. As Genmab prepares to engage with global regulators and present its findings at future medical meetings, the company is likely to attract increased interest from investors and partners alike. The success of petosemtamab could catalyze further investment in bispecific antibodies and novel targets, potentially reshaping treatment protocols in oncology. Competitors will need to respond with their own innovations or risk falling behind in a rapidly evolving market.

## Entities

- **Companies**: Genmab, Merus, Merck & Co.
- **Products**: petosemtamab, Keytruda, rinatabart sesutecan
- **Technologies**: bispecific antibody, immunoglobulin G1, antibody-drug conjugate
- **People**: Jan van de Winkel
- **Organizations**: European Society for Medical Oncology

## Key Concepts

bispecific antibody, overall survival, objective response rate, phase 3 trial, head and neck squamous cell carcinoma, acquisition, safety profile, cancer treatment

## Definitions

- **bispecific antibody**: A type of antibody that can bind to two different antigens, enhancing the immune response against cancer cells.
- **overall survival**: A measure of the length of time from diagnosis or start of treatment that patients are still alive.
- **objective response rate**: The proportion of patients whose cancer shrinks or disappears after treatment.
- **phase 3 trial**: A late-stage clinical trial that tests the effectiveness of a treatment in a larger patient population.
- **acquisition**: The process of obtaining control of another company, often through purchasing its shares.

## Use Cases

- treatment for PD-L1-positive recurrent or metastatic head and neck squamous cell carcinoma
- evaluation in second- and third-line recurrent or metastatic HNSCC
- application in colorectal cancer
- potential first-in-class treatment option
- improving overall survival in cancer patients
- enhancing objective response rates in clinical trials

## Frequently Asked Questions

**What is the significance of the phase 3 trial results for Genmab?**

The phase 3 trial results are significant as they demonstrate that the combination of petosemtamab and Keytruda can halve the risk of death in patients with a challenging type of cancer, marking a major milestone for Genmab.

**How does petosemtamab work?**

Petosemtamab is a bispecific antibody that binds to both EGFR and LGR5, targeting cancer cells more effectively and potentially improving treatment outcomes for patients.

**What are the next steps for Genmab after these results?**

Genmab plans to discuss the trial results with global regulators and intends to submit the full dataset for presentation at future medical meetings to further advance the development of petosemtamab.

**What is the projected market potential for petosemtamab?**

Analysts project that petosemtamab could generate peak sales of $4 billion in the treatment of head and neck squamous cell carcinoma alone, indicating a strong market potential.

**What other successes has Genmab achieved recently?**

In addition to petosemtamab, Genmab reported a phase 3 win for rinatabart sesutecan in treating platinum-resistant ovarian cancer, showcasing the company's ongoing success in oncology.

## Links

- [Read on Welcome.AI](https://welcome.ai/content/genmabs-bispecific-antibody-cuts-death-risk-by-50-in-cancer-trial)
- [Original source](https://www.fiercebiotech.com/biotech/genmabs-head-and-neck-cancer-bispecific-cuts-risk-death-half-ph3)

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Source: Welcome.AI | https://welcome.ai/content/genmabs-bispecific-antibody-cuts-death-risk-by-50-in-cancer-trial