Genmab Halts Cancer Drug Acasunlimab to Double Down on Blockbusters

COPENHAGEN, Denmark – December 29, 2025 – In a decisive strategic move, international biotechnology firm Genmab A/S announced it will cease all further clinical development of its investigational cancer therapy, acasunlimab. The decision, which underscores a disciplined shift in portfolio priorities, will allow the company to channel its resources toward a trio of late-stage programs it believes hold greater potential for both patients and shareholders.

Company officials clarified that the termination was not due to poor clinical results. On the contrary, the clinical profile for acasunlimab was described as “encouraging.” Instead, the move stems from a rigorous evaluation of the company's pipeline and the “evolving competitive landscape.” This pivot highlights the intense pressures within the pharmaceutical industry, where promising drugs can be shelved in favor of assets with a clearer path to market dominance or higher value creation.

This strategic realignment is designed to accelerate the development of what Genmab views as its most impactful future medicines, reinforcing its commitment to maximizing its return on investment and delivering transformative treatments.

A Calculated Pivot Toward Late-Stage Assets

The decision to discontinue acasunlimab is a direct result of Genmab's capital allocation framework, which prioritizes programs with the highest probability of success and commercial impact. By halting the acasunlimab program, Genmab is effectively doubling down on its most advanced assets, which are closer to potential regulatory approval and market launch.

“After careful consideration, we have decided to discontinue the acasunlimab program,” said Jan van de Winkel, Ph.D., Chief Executive Officer of Genmab. “Although the data have been encouraging, the compelling opportunities we see in our late-stage pipeline led us to focus our investments where we believe we can deliver the greatest benefit for patients and shareholders.”

The company is redirecting its focus and resources to three key programs:

• EPKINLY® (epcoritamab): A bispecific antibody that is already showing significant momentum in the market and in ongoing clinical trials.
• Petosemtamab: An immune-modulating antibody advancing rapidly in late-stage development for various cancers.
• Rinatabart sesutecan (Rina-S®): A next-generation antibody-drug conjugate (ADC) that represents a highly promising therapeutic modality.

Van de Winkel expressed strong confidence in the prioritized assets, stating, “We are highly energized by the momentum of EPKINLY, petosemtamab and Rina-S, and we remain committed to executing these programs with speed and rigor.” This focus on late-stage candidates is a common strategy for established biotech firms aiming to shorten the timeline to revenue generation and solidify their market position.

The Hard Realities of Drug Development

The shelving of a drug with an “encouraging” clinical profile casts a light on the complex and often brutal calculus of modern pharmaceutical development. In today's competitive environment, positive clinical data is merely one component of a successful drug program. Companies like Genmab must also weigh factors such as the size of the potential patient population, the strength of competing therapies already on the market or in development, and the projected cost of manufacturing and commercialization.

The reference to an “evolving competitive landscape” suggests that even if acasunlimab were to succeed in its trials, it might enter a crowded market or face superior competing products, thereby limiting its ultimate commercial potential. By cutting the program now, Genmab avoids spending hundreds of millions of dollars on late-stage trials and a potential marketing launch for a drug that might not become a best-in-class or first-in-class therapy. This type of disciplined portfolio management, while difficult, is often lauded by investors as a sign of shrewd and responsible leadership.

Financial Stability and Market Confidence

To reassure investors, Genmab explicitly stated that the decision to discontinue acasunlimab will not impact its full-year 2025 financial guidance. This announcement signals that the costs associated with shuttering the program are manageable and were likely anticipated within the company’s financial planning. It reinforces the message that the move is one of strategic optimization rather than a reaction to an unforeseen crisis.

By proactively managing its pipeline, Genmab aims to maintain a strong financial position while concentrating its formidable research and development engine on the assets most likely to become blockbuster drugs. This approach is consistent with the company’s long-term strategy to build a sustainable and highly valuable portfolio of innovative antibody medicines.

Genmab has a proven track record in this arena. Established over 25 years ago, the Copenhagen-based company has become a global leader in the field of antibody therapeutics. Its science is the foundation for eight approved medicines, a testament to its ability to successfully navigate the long and arduous path from laboratory discovery to patient bedside. With a robust late-stage pipeline and a global presence spanning North America, Europe, and the Asia Pacific region, Genmab is well-positioned to continue its mission of improving the lives of people with cancer and other serious diseases through its focused and strategic approach to innovation.