A Nature publication by U.S. scientists and BioNTech CEO Ugur Sahin demonstrates the potential and feasibility of individualized mRNA neoantigen vaccines for the treatment of pancreatic ductal adenocarcinoma, which is fatal in as many as 88% of patients and shows a response rate of less than 5% to existing therapies.

In an ongoing investigator-initiated phase I pilot study of the uridine mRNA lipoplex nanoparticle-based adjuvant Autogen Cevumeran, developed jointly with Roche subsidiary Genentech Inc, half of 16 patients treated with a combination of Roche's anti-PD-L1 antibody atezolizumab and BioNTech's vaccine showed strong induction of T cells directed against up to 20 patient-specific neoantigens. Subsequently, 15 patients received a modified four-drug chemotherapy regimen (mFOLFIRINOX, consisting of folinic acid, fluorouracil, irinotecan, and oxaliplatin).

Autogenous cevumeran was well tolerated except for one grade 3 adverse event previously reported at ASCO 2022. Using a mathematical strategy to track T-cell clones (CloneTrack) and functional assays, investigators demonstrated that vaccine-expanded T cells accounted for up to 10% of all T cells in the blood, re-expanded after a vaccine booster, and formed long-lived polyfunctional neoantigen-specific effector CD8+ T cells.

After a median follow-up of 18 months, patients with vaccine-expanded T cells who were classified as responders showed longer median relapse-free survival compared with patients without vaccine-expanded T cells. The company therefore says it is optimistic that it will be able to confirm the correlation in further extensive clinical trials.

A few days earlier, BioNTech reported a sharp drop in sales due to flagging sales of its Corona vaccine. The company has a contract with the U.K. government to provide the tumor vaccine to 10,000 British patients.

However, it is not the T-cell concentrations in the blood but their degree of tumor invasiveness that is considered critical to the success of cancer immunotherapies.