Imfinzi is one of AstraZeneca’s key growth drivers for 2025, with potential approvals in stomach and bladder cancers. The PD-L1 blocker brought in over $4.7 billion in sales last year.
AstraZeneca’s PD-L1 blocker Imfinzi outperformed standard of care at boosting event-free survival in certain types of stomach cancer, according to a late-stage readout posted on Friday.
In the Phase III MATTERHORN trial, AstraZeneca enrolled nearly 950 patients who had stage II to IVA gastric and gastroesophageal junction (GEJ) cancers. For its active treatment, the pharma combined Imfinzi with a chemotherapy regimen called FLOT—the current standard of care in this indication, consisting of the drugs fluorouracil, leucovorin, oxaliplatin and docetaxel.
Patients in MATTERHORN were treated with neoadjuvant Imfinzi plus FLOT before surgery, followed by adjuvant Imfinzi and FLOT, then Imfinzi monotherapy. Meanwhile, patients in the control arm were given perioperative FLOT alone.
AstraZeneca did not provide specific data in its news release on Friday, with the company revealing only that the Imfinzi combo elicited a “statistically significant and clinically meaningful improvement” in event-free survival, the study’s primary outcome, as compared with FLOT.
Overall survival (OS), a key secondary endpoint, was immature at the time of the analysis, but nevertheless showed a “strong trend” in favor of the PD-L1 inhibitor, according to AstraZeneca. MATTERHORN is an ongoing study and will continue to follow patients to get a mature readout of OS.
As for safety, Imfinzi’s adverse event profile was consistent with what had been established in prior studies, with no new signals of concern.
Imfinzi is an intravenously administered IgG1 monoclonal antibody which binds the PD-L1 ligand and blocks its downstream signaling cascade. Since the biologic was first approved in 2017, it has become a cornerstone of AstraZeneca’s business, bringing in more than $4.7 billion last year.
In a company presentation last month, AstraZeneca named Imfinzi as one of its key growth drivers for 2025, particularly looking forward to potential approvals in bladder and gastrointestinal cancers “to unlock [its] next wave of growth.” MATTERHORN is one of three studies that could help the pharma achieve this goal—alongside the POTOMAC and VOLGA programs in bladder cancer.
“Our focus is on novel combination approaches to overcome treatment resistance and extend immune responses, as well as leveraging immunotherapy in earlier disease stages where there is greater potential for a cure,” Nancy Ghattas, vice president, U.S. oncology commercial franchise head-immuno oncology at AstraZeneca, told BioSpace in an email. Imfinzi is central to this strategy, she added.
In its press announcement on Friday, AstraZeneca said it plans on taking MATTERHORN’s findings to global regulatory authorities, positioning Imfinzi as a perioperative treatment option for gastric and GEJ cancers. The pharma will also present complete data and analyses of MATTERHORN at an upcoming medical meeting.
Update (March 7): This story has been updated to include comments from AstraZeneca.
