German vaccine maker CureVac on Monday said that interim results from early trials showed that its investigational Covid-19 vaccine candidate, CvnCoV, appeared safe and triggered immune response among volunteers.
The vaccine candidate was generally well tolerated across all tested doses and induced strong binding and neutralising antibody responses in addition to first indication of T cell activation, the company said.
The Phase 1 study has enrolled to date more than 250 healthy individuals aged 18 to 60 years.
Individuals were vaccinated intramuscularly with CVnCoV at escalating dose levels of 2, 4, 6, 8 and 12 microgram on days 1 and 29.
Per dose level, the trial included up to 10 participants who had previously tested positive for a Covid-19 infection (seropositives) to further evaluate the safety and immunogenicity of CVnCoV in this sub-population.
The data support the decision to advance the 12 microgram dose in the upcoming pivotal Phase 2b/3 study, the company said.
"We are very encouraged by the interim Phase 1 data. It represents a critical milestone in our Covid-19 vaccine programme and strongly supports the advancement of our vaccine candidate," Franz-Werner Haas, Chief Executive Officer of CureVac, said in a statement.
"Following further data readouts and discussion with regulatory authorities, we remain fully committed and on track to initiate a pivotal Phase 2b/3 trial before the end of 2020."
While saying that no related serious adverse events were observed during the early trials, at 12 microgram, grade 3 adverse events occurred mostly after administration of the second dose and included fatigue, headache, chills, muscle pain, and to a lesser extent, fever.
All reported events were transient and resolved rapidly, usually within 24 to 48 hours, the company said.
CureVac said it intends to provide a detailed Phase 1 data overview and publication in a scientific journal in the coming weeks.
"These initial data show a robust and highly efficient immune response to our natural mRNA (messenger ribonucleic acid)-based CVnCoV vaccine candidate, including antibody and initial T cell responses at the level of a relevant panel of symptomatic convalescent patients," said Mariola Fotin-Mleczek, Chief Technology Officer of CureVac.
The company said that CVnCoV's mode of action mimics the natural immune response to the infection observed in recovered Covid-19 patients.
CVnCoV is currently also being investigated in a Phase 2a clinical trial in older adults in Peru and Panama.