The decision comes as BioNTech has chosen not to participate further in the programme under the existing collaboration agreement.
Despite this change, Genmab will still be required to pay BioNTech certain milestones and a tiered single-digit royalty on net sales.
Genmab is planning to initiate a Phase III study for acasunlimab in the second half of this year.
BioNTech’s decision to step back from the programme is claimed to be attributed to its portfolio strategy, although the clinical profile of acasunlimab remains promising.
The two companies will maintain their long-standing partnership in antibody science and will continue with other joint development programmes as per their expanded agreements from 2022.
Acasunlimab, also known as GEN1046, is a novel investigational PD-L1x4-1BB bispecific antibody.
It combines Genmab’s DuoBody technology platform with BioNTech’s immunomodulatory antibodies to potentially activate an antitumor response.
The drug’s mechanism focuses on conditional activation of 4-1BB on T cells and natural killer (NK) cells, which depends on the simultaneous binding of the PD-L1 arm.
BioNTech’s withdrawal from the acasunlimab programme is not expected to affect Genmab’s financial guidance for this year.
Genmab CEO Jan van de Winkel said: “Genmab’s partnership with BioNTech is a highly successful one. Together, we have demonstrated acasunlimab’s potential to impact patients with metastatic non-small cell lung cancer, as evidenced by the promising initial results presented at the 2024 American Society of Clinical Oncology Meeting.
“Genmab is exceptionally well-positioned to maximize the potential of acasunlimab, and we are confident about the prospect of taking acasunlimab into late-stage development as our second wholly owned Genmab asset in addition to Rina-S. We look forward to our continued partnership with BioNTech on other pipeline programmes.”