CureVac and GSK have picked the mRNA approach that will advance in the clinic for flu and COVID-19 after seeing phase 1 data on a handful of candidates. While analysts were happy to see the win, they were skeptical of the lack of updated variant data and limited population read-out—even going so far as to call the disclosure “half-baked.”
Germany-based CureVac said Friday that preliminary data from the early-stage trials for its COVID-19 and seasonal flu shots look good. The vaccines, which use CureVac’s second-generation mRNA backbone, produced an immune response and were generally well tolerated with no safety concerns.
The small disclosure boosted CureVac’s shares by 17% to $7.49 Friday morning, despite a data release that seemed to leave more questions than answers during a conference call Friday morning.
The companies were testing a selection of potential vaccines featuring modified and unmodified mRNA. The COVID program had two monovalent candidates, while the flu tests included an unmodified multivalent and a modified monovalent vaccine candidate. CureVac shared data on the modified, monovalent mRNA COVID-19 vaccine called CV0501 and the modified mRNA flu candidate named Flu-SV-mRNA.
CV0501 was tested in 30 subjects and produced neutralizing titers against the omicron variant BA.1 beginning at the lowest tested dose. The data available are only for the younger adult group, ages 18-64, while more information on the older demographic is forthcoming. The shot was generally well tolerated.
Flu-SV-mRNA was trialed against an unnamed licensed seasonal flu vaccine and showed antibody titers 3.3 times that of the comparator in younger adults. The shot was also well tolerated, according to the release. Data for older adults are pending.
But even without those pieces, GSK and CureVac have what they need to move forward with the modified vaccines this year. While CV0501 was assessed against omicron variant BA.1, the upcoming phase 2 study will feature monovalent and/or bivalent vaccine candidates that go after clinically relevant variants, according to CureVac. As for the flu shot, CureVac said the future clinical candidate will go after all four World Health Organization-recommended strains. A phase 1/2 trial will begin in mid-2023.
Analysts congratulated CureVac on the data during the conference call but had hoped to see a more robust read-out than what was presented Friday. They had plenty of questions about what was missing, including the older adult population, current variant data, a comparison to Moderna, a combination flu/COVID strategy and a firm timeline for phase 3 advancement.
One analyst asked CureVac CEO Franz-Werner Haas and interim Chief Development Officer Ulrike Gnad-Vogt why they didn’t wait until they had more to share, calling the omission of the older population “half-baked.” Haas defended the news release, saying that the idea was to show the platform is working after the company’s first generation COVID candidate failed in 2021.
“What we … have been showing you today is telling you something about the functioning and the workings of our mRNA technology, not that much with regards to what are the next steps in product development, which will come soon,” Haas promised. The limited data are meant to show that the platform has overcome the limitations seen in the first shot.
CureVac’s mRNA platform uses optimized mRNA to carry data to instruct the body to fight disease. Haas said in the company’s statement that the results validate the company’s cancer portfolio as well, since it uses the same tech.
Haas said “it’s a bit too early to say” whether a combination flu-COVID shot will be commercially viable, although mRNA platforms are able to respond to the latest variants quickly to allow new versions to be manufactured. This has been evidenced by CureVac’s peers, Moderna and BioNTech-Pfizer, which have released updated bivalent COVID shots for the 2022/2023 season.
The small Friday release included the BA.1 variant, whereas the Centers for Disease Control and Prevention is tracking BA.2, BA.4 and BA.5 at the moment. Gnad-Vogt said the BA.4 and BA.5 strains will be included in the upcoming trials, which will put the candidates up against a currently approved shot.
“Certainly, you can see that this is exactly where RNA is so interesting for these kinds of developments, is there are new strains, and then we will all see how this epidemiology will develop and what the next clinical trials will be,” Haas said.
Another analyst wanted to know how CV0501 stands up to Moderna’s offering, but the executives didn't bite. Haas explained that, while a comparison could be made with publicly available data on Moderna’s shot, the comparison would not be scientifically accurate because the two products were not tested against each other in the same study. That kind of test will come later, he promised.
The executives were peppered with questions about the timing of a potential phase 3 but didn’t have much to share beyond saying they need to analyze full data from the studies presented today before they can make a decision. A dose has not yet been selected for the next phase of clinical development.
The GSK partnership was signed in July 2020 in the height of the pandemic, but so far has notched a failure and a re-do. With the next-generation attempt now showing some fruit, Haas said conversations with GSK are happening around the future of the partnership and whether any other targets will be advanced.
“It is exciting to see these data, especially in contrast to what we've been seeing on the earlier construct—and this motivates, I can tell you,” the CEO said.
In the company’s earlier statement, Haas said CureVac will “enter 2023 as a competitive player in the development of mRNA therapies.”
Editor's Note: This story was modified at 3:23 p.m. ET on January 6, 2023, to clarify that CureVac is advancing modified mRNA vaccines, not individual candidates.