on Monday touted what it called positive early data from a trial of a combination cancer therapy that involves a messenger RNA cancer vaccine in an early test of mRNA applicability in cancer.
(ticker: BNTX) were down 1.7% in premarket trading. The stock is down 34% this year.
Before the Covid-19 pandemic, much of the focus of biotechnology companies working on mRNA technology—including BioNTech,
(CVAC)—was on applications in cancer.
Even as the early success of the Covid-19 vaccines has pushed the companies toward developing new mRNA-based infectious-disease vaccines, they retain extensive oncology pipelines.
At a medical conference over the weekend, BioNTech presented data from a continuing study of a treatment called BNT211, which combines what is known as a CAR-T cell therapy with a CAR-T cell amplifying RNA vaccine.
CAR-T therapies use a patient’s own T cells to target cancer cells and destroy them. The vaccine, known as CARVac, is used to amplify the effect of the CAR-T treatment.
BioNTech said in its statement Monday that in the small group of 16 patients who received the therapy, who suffered from a range of cancers, there was a 43% overall response rate, meaning that six of the 14 evaluable patients showed a “partial response.”
“Seeing first anti-tumor effects even at the lowest CAR-T cell dose in this heavily pretreated patient population is truly remarkable and points to the potential of our CAR design and our CARVac approach,” said Dr. Özlem Türeci, BioNTech’s chief medical officer, in a statement.
Not all of the patients in the trial received both the CAR-T therapy and CARVac. According to a press release from the American Association for Cancer Research, at whose conference the data were first presented on Sunday, of the six patients who showed a partial response, only two had received CARVac.
While other CAR T treatments have been approved, there has been little success so far in solid tumors. “CLDN6 was never targeted before with cellular therapy, but in our study, this approach is already showing efficacy that may be better than the data from other CART trials in solid tumors,” said Dr. John Haanen of the Netherlands Cancer Institute, who conducted the study, in the AACR press release.
The muted investor reaction on Monday may be due to the fact that few of the patients actually received the mRNA vaccine boost. More data may be needed to give investors confidence in CARVac and other mRNA-based oncology drugs.
Haanen told the biotech industry news site Endpoints News that it remained difficult to say how much of the response was due to the CAR-T, as compared with the mRNA vaccine.
Write to Josh Nathan-Kazis at firstname.lastname@example.org