CureVac's lead mRNA drug is down but not out, says CEO

CureVac had some disappointing news to report to investors at the J.P. Morgan Healthcare Conference this week after its lead drug failed a phase 2b trial in prostate cancer.

The German specialist in mRNA-based drugs said CV9014 was unable to meet its primary objective of improving survival in the trial, which involved patients with asymptomatic or minimally symptomatic metastatic castration-resistant prostate cancer (mCRPC).

The vaccine also failed to improve progression-free survival compared to placebo, proving once again that having deep pockets—CureVac counts billionaires Bill Gates and Dietmar Hopp among its backers—is no guarantee of success in biotech development.

Chief executive Ingmar Hoerr insists however that all is not lost for CV9014 and other mRNA drugs, arguing that they could be transformed by being administered alongside checkpoint inhibitors such as Merck & Co's Keytruda, Bristol-Myers Squibb's Opdivo and Roche's Tecentriq.

Hoerr told that the key lesson from the trial is that "mRNA is not enough on its own—you have to break tolerance and you have to make it more immunogenic." He reckons the key will be to give CV9104 in combination with checkpoint inhibitors, pointing to a "much more potent immune response" seen in preclinical testing.

"We're already planning with our partner, Boehringer Ingelheim, to start clinical trials of mRNA in combination with checkpoint inhibitors," he said, pointing out that these drugs were not available when the CV9104 study started. The two companies have been working together since 2014 on a program focusing on CureVac's CV9202 mRNA candidate for lung cancer.

On the plus side, CureVac was able to report no safety issues with the drug—toxicity has been a perennial concern for mRNA drugs as they are large molecules that can stimulate immune reactions.  

"Having administered our RNA technologies to more than 450 human subjects and having conducted eight different clinical studies, we are confident that it can be administered safely," he said.

CureVac is one of a handful of biotech companies developing mRNA-based drugs, with another prominent player—Moderna—providing the first detailed information on its pipeline at JP Morgan this week.

Meanwhile, the company was also able to provide some positive proof-of-concept clinical data at the conference on CV7021 for rabies, its lead preventative vaccine candidate, showing that it was able to stimulate an immune response against viral antigens.

"These results … pave the way for us to advance more potent prophylactic vaccine formulations into the clinic," said Hoerr.